A TOTAL EVIDENCE ANALYSIS OF THE EVOLUTIONARY HISTORY OF THE
THUNNOSAUR ICHTHYOSAURS
Jessica Danielle Lawrence
A Thesis
Submitted to the Graduate College of Bowling Green
State University in partial fulfillment of
the requirements for the degree of
MASTER OF SCIENCE
December 2008
Committee:
Dr. Margaret (Peg) Yacobucci, Advisor
Dr. Dan Pavuk
Dr. James E. Evans
© 2008
Jessica Danielle Lawrence
All Rights Reserved
iii
ABSTRACT
Margaret (Peg) Yacobucci, Advisor
Ichthyosaurs first appear in the Early Triassic with an elongate, lizard-shaped
anatomy. The most derived ichthyosaurs, including the Late Triassic to Early Jurassic
Eurhinosauria and the Late Triassic to Mid Cretaceous Thunnosauria, evolved more
streamlined fish-shaped bodies. A species-level cladistic analysis of this derived group of
ichthyosaurs, using 60 characters for 17 outgroup taxa and one ingroup taxon, was
conducted using PAUP* (Swofford, 1998). The new analysis is compared to that of
Motani’s (1999b) genus-level analysis of ichthyosaurs by looking at the clade-defining
character state changes in each. I use a total evidence approach, meaning a detailed
phylogenetic analysis plus data on stratigraphic and geographic occurrences, to answer
two questions. First, is it more plausible to place Stenopterygius as a sister to the
Ophthalmosauria or to permit the longer ghost lineage for Ophthalmosauria that would be
required if Ichthyosaurus is its sister taxon, a question suggested by Motani (1999b)? A
phylogenetic tree incorporating known stratigraphic ranges was constructed, based on the
species-level cladistic analysis, to help quantify the stratigraphic debt using the relative
completeness index (RCI), stratigraphic congruency index (SCI) and the gap excess ratio
(GER). When a species-level analysis was performed, four previously defined clades fell
apart, including Leptonectes, Stenopterygius, Eurhinosauria and Ophthalmosauria.
Hence, Motani’s (1999b) suggestion that Stenopterygius and Ophthalmosauria be placed
as sister taxa is not supported by this analysis; nor is placing Ichthyosaurus as the sister
group supported. Rather, the ophthalmosaurian taxa were pulled down the tree in the
iv
species-level analysis, creating even longer ghost lineages than were previously present.
These longer ghost lineages are the primary cause of the observed stratigraphic debt,
along with Eurhinosaurus longirostris, Leptonectes solei, and Excalibosaurus costini.
Despite these increases, overall the species-level phylogeny is more stratigraphically
parsimonious than Motani’s (1999b) genus-level one. The second question this study
addressed was to determine whether the radiation of the Ophthalmosauria was influenced
by the opening of new marine habitats from the widening of the Atlantic and/or the
appearance of morphological novelties. The radiation of the Ophthalmosauria into North
and South America coincides with the widening of the North and South Atlantic during
the Late Jurassic, as well as nine synapomorphies involving changes to the ear and lower
jaw region, numerous changes in the forefins (including extra digits) and pelvis. These
characters may be associated with adaptations to more efficient swimming in open ocean
habitats, helping the groups’ biogeographic dispersion. Hence, both tectonic events and
the evolution of morphological innovations likely influenced the radiation of the
Ophthalmosauria.
v
This paper is dedicated to my family with a special thanks to my Mom, Kim R.
Lawrence. Without her constant love, support, and encouragement this paper would not
have gotten done. I would also like to sincerely thank my Grandma Helen Franz
Lawrence, Grandpa Loren Eugene Richardson, and Grandma Alice Faye Richardson.
Their love and support of my education has been overwhelming and without it I know I
would not be where I am today. Grandma and Grandpa Richardson, I wish you were still
here to see what all your love and support has helped me accomplish.
vi
ACKNOWLEDGMENTS
I would first and foremost like to thank my advisor Peg Yacobucci, without her
guidance I would have been lost at so many stages of this project. Thank you for always
taking the time to answer my questions, even when you were very busy and the
explanation took a bit longer than expected. Thank you to my committee members for
taking the time to help make my thesis stronger. I would also like to thank the Geology
department for their support as well as the Richard D. Hoare Research Scholarship and
Katzner Bookstore Award for funding my research. I would also like to thank Kevin
Seymour (ROM) and Patricia Holroyd (UCMP) for their help when looking at
specimens; they were an amazing help, especially with my quick day visit to Toronto. A
big thank you to all my fellow graduate students for being there to listen, help and
provide a fun outlet for all the frustrations that school can bring, I will never forget these
times. A special thanks to Mary Scanlan for being an amazing office mate, however short
it was and for helping me get through my first year, as well as listening to my rants about
this paper. A special thanks to Kelsey Garner and Megan Castles who made this second
year incredibly entertaining. I would also like to thank my family again, for listening to
my frustrations and helping to keep me motivated when I was in need of it. Thanks to my
mother for traveling with me to Canada so that I did not have to make that drive by
myself.
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TABLE OF CONTENTS
Page
CHAPTER I. INTRODUCTION...........................................................................................
1
Background ................................................................................................................
2
Objectives ..................................................................................................................
10
CHAPTER II. METHODS ...................................................................................................
12
Taxa and Characters...................................................................................................
12
Phylogenetic Analysis................................................................................................
13
Stratigraphic Debt Analysis .......................................................................................
15
CHAPTER III. RESULTS ....................................................................................................
19
Phylogenetic Analysis................................................................................................
19
PAUP Cladogram...........................................................................................
19
Evolutionary Tree ..........................................................................................
26
Phylogenetic vs. Stratigraphic Parsimony .................................................................
29
Radiation of the Ophthalmosauria .............................................................................
30
CHAPTER IV. DISCUSSION..............................................................................................
31
CHAPTER V. SUMMARY AND CONCLUSIONS ...........................................................
35
REFERENCES ......................................................................................................................
37
APPENDIX A. CHARACTER DESCRIPTIONS ................................................................
43
APPENDIX B. SPECIES DATA .........................................................................................
51
APPENDIX C. UNINFORMATIVE CHARACTERS ........................................................
56
APPENDIX D. CALCULATING MIG FOR GER..............................................................
58
APPENDIX E. CALCULATING Gmin and Gmax FOR GER ................................................
59
vii
APPENDIX F. GENUS-LEVEL CHARACTER STATE CHANGES................................
60
APPENDIX G. SPECIES-LEVEL CHARACTER STATE CHANGES.............................
67
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LIST OF FIGURES
Figure
Page
1
Ophthalmosaurus from the Upper Jurassic................................................................
3
2
Body evolution of ichthyosaurs .................................................................................
4
3
Cladogram of diapsid reptiles ....................................................................................
5
4
Ichthyopterygian phylogeny ......................................................................................
7
5
Examples of ghost lineages and ghost taxa................................................................
7
6
One tree from Motani’s (1999b) data set that shows where the character state changes
occur ………………………………………………………………………………… 20
7
Strict consensus tree from species-based analysis showing the one polytomy present 21
8
Bootstrap and jackknife support for subclades………………………………………
22
9
Character state changes for species-level analysis.....................................................
24
10
Phylogenetic tree for species ....................................................................................
27
11
Consensus tree showing the stratigraphic interval during which each of the species is
present and its common geographic locations…….. ................................................
28
ix
LIST OF TABLES
Table
1
Page
Average duration of stages and ammonite biozones..................................................
16
1
INTRODUCTION
Ichthyosaurs, the fish shaped reptiles from the Mesozoic, are known for their dolphin-like
looks and fast swimming. Ichthyosaurs occur from the Triassic to the Mid-Cretaceous (Motani,
2005a). Much research has been done on the morphological possibilities of these animals, but not
as much has been done on the phylogenetics, or evolutionary relationships, of the group. In the
early phylogenetic studies, many paleontologists took the “Jurassicocentric” view of
ichthyopterygian evolution (McGowan and Motani, 2003). This view took a top-down approach
to the evolution of the group and traced characters in the reverse direction or from the Jurassic to
the Triassic (McGowan and Motani, 2003). Some paleontologists took a more bottom-up
approach, but this never seemed to emerge as the popular view (McGowan and Motani, 2003).
These early phylogenetic ideas came under further debate when cladistics became more
dominant as a methodology and more specimens were found at a lower stratigraphic level. The
first cladogram to use the Early Triassic “proto-ichthyosaur” Grippa longirostris, almost 50
years after its discovery, was conducted by Mazin (1982) (McGowan and Motani, 2003).
Calloway (1989) did the first parsimony-based analysis in 1989, focusing on shastasaurids, that
was then improved by Dal Sasso and Pinna (1996) by adding a newly described specimen
(McGowan and Motani, 2003). Motani did a general analysis of the majority of the known
ichthyosaurs at the genus level in 1999b, and some work has been done on the phylogeny of the
Family Mixosauridae (Motani, 1999b; Jiang et al., 2005). According to McGowan and Motani
(2003), Sander (2000) published another tree, which is similar to that of Mazin (1982), however
he did not include seven of the characters in the data matrix, and it is therefore not possible to
reproduce his results. Others such as Maisch and Matzke (2000) and Fernández (2007) have
done similar analyses. Maisch and Matzke’s (2000) analysis used an imaginary taxon as the
2
outgroup that was coded as all zeros for the characters, using three ancestral specimens to
polarize the character states (McGowan and Motani, 2003). The major problem with this
approach was that the authors did not explain how the characters were polarized. Fernández
(2007) re-described a specimen of Caypullisaurus from the Neuquén Basin of Argentina, and
used characters that dealt with the sclerotic ring; her cladistic results were similar to those of
Motani (1999b).
The more derived clades of Ichthyosauria have not been investigated on a more detailed
level. The present study takes a portion of the phylogenetic tree constructed by Motani (1999b)
and conducts a more detailed analysis of one section of this tree. The goal is to clear up some of
the unresolved clades present in Motani’s (1999b) analysis, because the more primitive groups
have been removed and therefore do not clutter up the analysis.
Background
Ichthyosaurs were originally made famous by Mary Anning’s collections in the 1800s
(McGowan, 1991). Ichthyosaurs had a unique morphology that has interested many
paleontologists and amateur fossil collectors for many years, including: large eyes (Motani,
1999b), streamlined body (McGowan, 1991), and large numbers of phalanges or finger bones.
The fish-like shape of the ichthyosaur can be seen in Figure 1 and is characteristic of the more
derived ichthyosaurs. In contrast more primitive ichthyosaurs are snake- or lizard-like and do not
have the distinctive shark-like tail. The evolution of the ichthyosaurs includes the development
of a larger eye, a more streamlined body and a more shark-like tail, as can be seen in Figure 2.
Due to these features, these reptiles are considered the most specialized of the marine reptiles
(Carroll, 1988). These reptiles are classified as Euryapsida due to the presence of an upper
temporal opening in the skull and solid cheek. The classification of Euryapsida is still
3
controversial, as many think that Euryapsida is just a modification of the Diapsida. Ichthyosaurs
are thought to swam like tunas and other fast swimming fish due to their streamlined shape
(Motani, 2002). The limbs of the ichthyosaur include many phalange bones and the animals may
have a slight curve at the end of the tail (Carroll, 1988). In some ichthyosaurs, there is a
noticeable bend in the tails in the caudal vertebra, which are referred to as the apical centra. In
the apical centra there are vertebrae that are wider dorsally than ventrally, making the last part of
the tail bend downward (McGowan and Motani, 2003). Before the wedged shaped vertebrae
were discovered, this bend in the tail was thought to be a preservational artifact.
Figure 1. Ophthalmosaurus from the Upper Jurassic. The skeletal structure is 3.5 meters long;
Streamlined body is a reconstruction. Modified from Carroll, 1988.
Ichthyosaurs are unique creatures and so it is still controversial as to where exactly they
are placed on a cladogram relative to other amniotes (McGowan and Motani, 2003), as seen in
Figure 3. Figure 3 shows ichthyosaurs placed with Lepidosauromorpha (node 3), but Caldwell
(2002) places them within the Euryapsida, which contains most other marine reptiles (node 4).
Calloway (1997) even places ichthyosaurs outside of node 2, separating them even more from
the other marine reptiles. McGowan and Motani (2003) also point out that most major vertebrate
4
groups have been suggested as a possible sister group to ichthyosaurs, further highlighting the
ambiguity of their placement.
Figure 2. Body evolution of ichthyosaurs. Modified from McGowan and Motani, 2003.
5
Figure 3. Cladogram of diapsid reptiles. Note where Euryapsida and ichthyosaurs are placed with
respect to other diapsid reptiles. Modified from Benton, 2000.
Regardless of where the Ichthyosauria are placed within Diapsida, the group can be
subdivided into subclades. The Thunnosauria are the most derived and youngest ichthyosaurs
and are distinguished through the ratio of forefin to hindfin (forefin is at least two times the
length of the hindfin, Motani, 1999b) (Figure 4). Within this clade is the Ophthalmosauria, which
first appear in the Late Jurassic after a large gap in the Middle Jurassic record. Ophthalmosauria
is defined by the absence, or extreme reduction of the basioccipital peg, the basioccipital
extracondylar area having a narrow band of concavity, the angular lateral exposure being at least
as high and anteriorly as the surangular exposure, the ridge of the humerus being plate-like, and
the presence of the manual anterior sesamoid e and the digit distal to it. In addition, the group is
well known for its large eyes (Motani, 1999b).
One interpretation of this large gap in the Middle Jurassic ichthyosaur record is that
Ophthalmosauria have a long ghost lineage (Motani, 1999b). A ghost lineage is a lineage for
6
which a fossil record does not exist but whose presence is inferred from the phylogenetic
relationships, and can be attributed to the imperfection of the fossil record (Figure 5). Ghost
lineages are determined by a comparison of the phylogenetic tree and the occurrence of the
fossils in the stratigraphic record. Ghost lineages or ranges are often expanded to cover the
interval of time from the first occurrence of a sister group to the taxon in question to that taxon’s
first appearance (Hammer and Harper, 2006). An example of a ghost lineage can be seen in
Figure 5. Ghost lineages are one way to represent stratigraphic debt, or the mismatch of
phylogenetic and stratigraphic patterns. Another way stratigraphic debt is represented is via
ghost taxa. A ghost taxon is a hypothetical taxon for which there is no fossil record, but which
must be inserted into the phylogenetic tree for the biostratigraphic data to be congruent (Figure
5) (Smith, 1994). Stratigraphic debt can be quantified using the stratigraphic congruence index
(SCI) (Huelsenbeck, 1994), relative completeness index (RCI) (Benton and Storrs, 1994) and the
gap excess ratio (GER) (Willis, 1999) (Hammer and Harper, 2006).
When constructing a phylogenetic tree, the goal is to find the most parsimonious tree, that
is, the one with the fewest number of required character state changes. This is done by
constructing all the trees possible, and calculating the total length of each (Hammer and Harper,
2006). According to Motani (1999b), placing Stenopterygius as the sister group to the
Ophthalmosauria (as suggested by Godefroit (1993), Maisch and Matzke (2000), and Sander
(2000); see Figure 4) would only make the phylogenetic tree one step longer. This tree topology
would greatly reduce the length of the ghost lineage required for the Ophthalmosauria. Hence,
making the tree one step longer and therefore less phylogenetically parsimonious would make it
more stratigraphically parsimonious.
7
Figure 4. Ichthyopterygian phylogeny. Modified from Motani’s (1999b) phylogenetic analysis of
ichthyopterygians.
Figure 5. Examples of ghost lineages and ghost taxa. Modified from Lane et al., 2005
8
In addition to the problem of phylogenetic versus stratigraphic parsimony, there is a need
to explore the causal factors driving the polytomy of this last, most derived clade of
ichthyosaurs. A polytomy is a branching pattern on a cladogram where two or more unresolved
clades collapse into one node (Hammer and Harper, 2006). The clades present in the polytomy
have symplesiomorphies, or ancestral character states inherited from a common ancestor
(Hammer and Harper, 2006). In contrast, the clades in the polytomy do not have any
synapomorphies, or derived character states that are phylogenetically informative, in common
(Hammer and Harper, 2006). According to Motani’s (1999b) phylogenetic tree (Figure 4), there
is an initial polytomy including the Eurhinosauria, Temnodontosaurus and the Thunnosauria as
well as a polytomy among the genera that make up Eurhinosauria. These polytomies could be
due to radiations that occurred during the Middle to Upper Jurassic, which is when the Atlantic
was starting to form.
An evolutionary radiation involves speciation events occurring in a short interval of time,
where the new species all come from a common ancestor; hence, they have symplesiomorphies
and autapomorphies, but no synapomorphies (shared derived characters) that could be used to
resolve branching order. A radiation is one potential explanation for the occurrence of a
polytomy on a cladogram, but it is not the only explanation. A polytomy may have formed
because of unknown or missing character states in the data matrix. An example of this would be
two species, one only being known for the skull and the other known for everything but the skull.
In this example it is impossible to resolve the relationship between the two.
If the polytomy is due to a rapid evolutionary radiation, two factors may have been
involved: 1) it was triggered by a morphological innovation that evolved in this clade, and 2) it is
due to biogeographic expansion into new marine environments being created due to the rifting of
9
the supercontinent Pangea, such as the epicontinental seas of southern South America. Recent
work has, in fact, focused on the ichthyosaurian record of the southern continents. An analysis by
Fernández et al. (2005) was based on measurements taken from the sclerotic ring of the South
American ophthalmosaurian Caypullisaurus. The objective of Fernández et al. (2005) was to
compare the size of the eyes of these specimens between juvenile and adult ichthyosaurs. The
main objective was not a phylogenetic analysis, but they did present a phylogenetic hypothesis.
The data for the analysis were taken from Motani’s (1999b) analysis (mentioned above) and their
own measurements from five specimens of Caypullisaurus, and four specimens of other
ophthalmosaurians, and data from about Temnodontosaurus taken from McGowan (1994). This
analysis was consistent with Motani’s findings, but has some species added to the phylogenetic
tree.
Fernández has written additional papers about ichthyosaurs from Argentina, which are
useful for evaluating the biogeographic expansion of the Ophthalmosauria (2001, 2003, 2007;
Fernández et al., 2005; Fernández and Aguirre-Urreta, 2005). The evidence found by Shultz et
al. (2003) supports the proposal of Fernández et al. (2005) that extension of the geographic range
of ichthyosaurs into the now closed Rocas Verdes (South Africa) backarc basin suggests that the
seaway could have been an important part of the migratory pathway to the Atlantic Ocean from
Northwest Europe. Extension was occurring in the Early Jurassic in South America, as evidenced
by the rift basins present on the eastern side of the Andean mountain range (Shultz et al., 2003).
This rifting represents the start of the modern South Atlantic Ocean. Based on the presence of
mafic oceanic crust in the Rocas Verdes Basin, the continent was separated in the latest Jurassic
or Early Cretaceous. Remains of ichthyosaurs and other reptiles have been found in the Neuquén
Basin, which is Tithonian-Valanginian in age (Gasparini and Fernández, 1997). There are also
10
deposits found in the Rocas Verdes rift basin that are from the Early Cretaceous, specifically the
Tobifera and Zapata Formations (Wilson, 1991). An ichthyosaur has been discovered in the
Torres del Paine National Park, Ultima Esperanza region of southern Chile, and is interpreted as
from the lower Zapata Formation (Lower Cretaceous) (Shultz et al., 2003). This biogeographic
pathway is also supported by the presence of bivalves Megacucullaea (Reyment and Tait, 1972)
in both Africa and Patagonia and by some belemnite faunas (Mutterlose, 1986). Ichthyosaur
teeth have also been found on the Antarctica peninsula, meaning that ichthyosaurs were present
in this area during the late Jurassic to the Early Cretaceous time (Shultz et al., 2003).
Objectives
The objective of this study is to conduct a phylogenetic analysis of the most derived
Ichthyosauria, including the clade Eurhinosauria, the genus Temnodontosaurus, and the clade
Thunnosauria, using information from multiple species of each genus (Figure 4), and including
species for which I have collected my own data as well as previously published descriptions
(Bardet, 1992; Dal Sasso and Pinna, 1996; Fernández, 2001, 2007; Fernández and AguirreUrreta, 2005; Fernández et al., 2005; Godefroit, 1993; Huene, 1922; Jiang et al., 2005; Lydekker,
1889; Maxwell and Caldwell, 2006; Maisch and Matzke, 1997, 2000; Mazin, 1981, 1982;
McGowan, 1976, 1994; McGowan and Motani, 2003; Motani, 1997, 1999a, 1999b, 2005a,
2005b; Sander, 2000, Shultz et al., 2003; and Wade, 1990). In the present study, a more detailed
analysis of the taxa within the most derived group of ichthyosaurs, the Thunnosauria, and their
sister groups, the Eurhinosauria and Temnodontosaurus, has been performed to help answer
phylogenetic, morphological, and paleogeographical questions about these ichthyosaurs. I use a
total evidence approach, meaning a detailed phylogenetic analysis plus data on stratigraphic and
geographic occurrences, to answer two questions. First, is a long ghost lineage more plausible
11
than placing Stenopterygius as a sister to the Ophthalmosauria, a question suggested by Motani
(1999b)? This can be determined by the concept of parsimony. In a phylogenetic context,
parsimony involves determining which cladogram has the fewest changes in character states. In
the case of the stratigraphic record, parsimony involves determining which phylogenetic tree has
the fewest range extensions and ghost lineages. What needs to be considered is whether or not it
is better to have a more parsimonious cladogram or a more parsimonious stratigraphic record?
Second, if the polytomy cannot be resolved with a species-based study, then is the radiation of
this derived clade of ichthyosaurs during this time due to the appearance of a morphological
innovation as documented by character state changes in the phylogenetic analysis or to the rifting
apart of Gondwana during this time to produce new ocean basins (Tethys, South Atlantic and
Rocas Verdes, South Africa), and hence new habitat space for open marine ichthyosaurs to
invade, or both?
12
METHODS
Taxa and Characters
To help decide if the cause of the polytomy of derived ichthyosaurs could be determined,
I recollected morphological data for specimens on the species level, as opposed to the genus
level presented in Motani (1999b). The data was obtained from specimens at the Royal Ontario
Museum (ROM) in Toronto, Canada, and the University of California Museum of Paleontology
at Berkeley (UCMP). Characters and character codes used are listed in Appendix A, while the
data matrices are presented in Appendix B. I was able to view the following pertinent species:
Stenopterygius quadrisscissus (UCMP 61201, 61202, 61203), a cast of Ichthyosaurus
intermedius (UCMP137398), a partial skull of Ichthyosaurus communis (ROM 28964),
Leptonectes tenuirostris (ROM 47698), Leptonectes moorei (ROM 52087), and
Excalibosauresus cabrini (ROM 26027). When collecting data on specimens from the literature,
I used the list of currently accepted taxa in McGowan and Motani (2003). I could not find
primary literature on some of the species (e.g., Arkhangelsky, 1998; Efimov, 1999; and Owen,
1881), while, for others, I could not use the primary literature due to the lack of pictures or lack
of quality pictures (e.g., McGowan, 1986; Kuhn, 1946; and Lydekker, 1888). Some articles had
the specimen redrawn, but I was unable to use those images either because the cranial sutures
were not drawn in, and these are pertinent for the characters used. There were two species,
Nannopterygius enthekiodon and Stenopterygius hauffianus for which I was able to collect a
small number of characters, but I did not feel that there was enough information to be valuable in
this analysis. These two species were therefore dropped from the analysis.
I focused on anatomical characteristics used by Motani (1999b) and Fernández (2007)
when looking at specimens. I used all 105 characters from Motani (1999b) but only used seven
13
from Fernández (2007) (characters 1, 2, 4, 7, 16, 19 and 21). These were characters that had not
been used in previous studies but I thought would be helpful in separating species; all characters
are listed in Appendix A.
My final dataset combined the results from my own observations of specimens and data
collected from the primary literature with the datasets from Motani (1999b) and Fernández
(2007) into a data matrix that was then reduced to a 18 operational taxonomic units (OTU), 112
character matrix compatible with the parsimony-based phylogenetic software package PAUP* or
Phylogenetic Analysis Using Parsimony Version 4.0b10 (Swofford, 2001) (data matrix listed in
Appendix B). PAUP* (Swofford, 2001) found that of my 112 characters, 52 of those were
parsimoniously uninformative, including 22 characters that were constant. These characters are
listed in Appendix C. So in reality, a character matrix of 18 OTU and 60 characters produced the
phylogenetic results. The reason so many of the characters were constant is due to a lot of
missing data, which may reflect the way many specimens are preserved. Also, since Motani’s
(1999b) analysis included all ichthyosaurs, many of his characters varied only in the less derived
groups.
Phylogenetic Analysis
In these analyses all characters were unweighted, and polymorphisms were included,
meaning that some characters were coded with more than one state. For example, character 33
(overbite) can be absent or slight (0) or can be clearly present (1) within specimens that are
plainly the same species based on other characters. PAUP* (Swofford, 2001) reads this coding
as indicating that this character could be one or the other state in a single taxon, not necessarily
both at the same time. The reason that the characters were unweighted is because there is no
evidence that one character is more important than another. This will also keep assumptions in
14
this analysis to a minimum. Including polymorphisms can lead to more uncertainty in the final
tree; however, they were included here to best reflect the true distribution of character states.
I conducted two separate phylogenetic analyses, one using Motani’s (1999b) original
dataset to determine which characters were supporting the clades that Motani’s (1999b) genuslevel analysis had produced. The second used an expanded database including seven characters
from Fernández (2007) and was done at the species level for derived ichthyosaurs only. The first
analysis was performed to help understand the radiation that is of interest in this study. I re-ran
Motani’s (1999b) original published dataset in PAUP* (Swofford, 2001) so that I could mark the
character state changes that supported each sub-clade. There are 33 OTUs and 105 characters in
the character matrix. Motani forced certain taxa to be the outgroup in PAUP* (Swofford, 2001)
and I did not recreate that for the purposes of this study. I placed Petrolacosaurus as the
outgroup, because it was the most primitive according to Motani’s (1999b) interpretation. The
changes in character states help show how the clades that were created in Motani’s (1999b)
analysis are defined. This information was then used to help me to define and interpret the clades
produced by my second analysis.
The second analysis included seven new characters and the data that I collected from the
museums and from the primary literature by species. This analysis was run to determine if the
polytomies seen in the genus-level analysis could be resolved. I chose the genus placed as the
sister taxon to my group of interest in Motani’s (1999b) analysis, Suevoleviathan, as the
outgroup because it is the logical sister group to the clade of interest. My analysis was done at
the species level (other than for the outgroup), to produce a more detailed evolutionary tree for
the derived ichthyosaurs. PAUP* (Swofford, 2001) was used to find the most parsimonious tree
and jackknife and bootstrap analyses (Felsenstein, 1985) were run to determine how well
15
supported each of the clades are. I determined where the character state changes occur to see
what is defining the clades that are now present.
A jackknife analysis randomly removes either taxa or characters from the original data
and then the analysis is rerun and repeated as many times as specified. The output then shows by
percentage how many times during that analysis each sub-clade occurred. If a subclade appears
over 70% of the time, it is considered a strongly supported grouping. Bootstrap analysis
(Felsenstein, 1985) is similar to jackknife but it randomly samples the data, usually only
characters, and then produces a brand new dataset that is the same size as the original but can
have duplication of different characters while omitting others. This analysis is rerun as many
times as specified and then the output is interpreted in a similar way as for jackknifing. If the
bootstrap value for a subclade is 70% or above, there is a 95% probability that the subclade is
real (Hillis and Bull, 1993).
Stratigraphic Debt Analysis
The Gap Excess Ratio (GER) (Willis, 1999), Relative Completeness Index (RCI) (Benton
and Storrs, 1994), and Stratigraphic Congruence Index (SCI) (Huelsenbeck, 1994) were
calculated by hand. These indices reflect how well supported the specific cladogram is when
compared to the stratigraphic record. To do the following calculations, time intervals needed to
be determined. I used the stratigraphic occurrence data for all ichthyosaur species, detailed by
ammonite biozone, presented by McGowan and Motani (2003, Table 2). Absolute date ranges
for all the ammonite biozones do not exist, but I was able to get the absolute ages for the stages
from the International Commission on Stratigraphy (2007), listed in Table 1. The durations of
the stages were determined in millions of years and then divided equally among the ammonite
biozones, assuming that each ammonite biozone within a stage was the same length (McGowan
16
and Motani (2003) used this same simplifying assumption). Ammonite biozone durations ranged
from 0.31 to 3.25 million years (mean=1.28 m.y., standard deviation = 0.75 m.y.). These
different ammonite biozone ranges were then used to calculate the stratigraphic gap and duration
lengths discussed below. Because many of the stratigraphic gaps of interest are so long,
deviations from the assumption of equal biozone duration would have only a small impact on the
overall estimation of stratigraphic debt.
Table 1. Average duration of stages and ammonite biozones. This table shows the dates of the
stages of interest along with the number of ammonite zones present and the estimated
duration of those ammonite zones that were used to calculate the stratigraphic gaps.
Dates from the International Commission on Stratigraphy (2007).
Stage
Start Date
(Ma)
End date
(Ma)
Rhaetian
Hettangian
Sinemurian
Pliensbachian
Toarcian
Aalenian
Bajocian
Bathonian
Callovian
Oxfordian
Kimmeridgian
Tithonian
Berriasian
Valanginian
Hauterivian
Barremian
Aptian
Albian
Cenomanian
Turonian
203.6 +/- 1.5
199.6 +/- 0.6
196.5 +/- 1.0
189.6 +/- 1.5
183.0 +/- 1.5
175.6 +/- 2.0
171.6 +/- 3.0
167.7 +/- 3.5
164.7 +/- 4.0
161.2 +/- 4.0
155.6 +/- 4.0
150.8 +/- 4.0
145.5 +/- 4.0
140.2 +/- 3.0
133.9 +/- 2.0
130.0 +/- 1.5
125.0 +/- 1.5
112.0 +/- 1.0
99.6 +/- 0.9
93.6 +/- 0.8
199.6 +/- 0.6
196.5 +/- 1.0
189.6 +/- 1.5
183.0 +/- 1.5
175.6 +/- 2.0
171.6 +/- 3.0
167.7 +/- 3.5
164.7 +/- 4.0
161.2 +/- 4.0
155.6 +/- 4.0
150.8 +/- 4.0
145.5 +/- 4.0
140.2 +/- 3.0
133.9 +/- 2.0
130.0 +/- 1.5
125.0 +/- 1.5
112.0 +/- 1.0
99.6 +/- 0.9
93.6 +/- 0.8
89.3 +/- 1.0
Stage
Number of
Duration Ammonite
(m.y.)
Biozones
4.0
3.1
6.9
6.6
7.4
4.0
3.9
3.0
3.5
5.8
4.8
5.3
5.3
6.3
3.9
5.0
13.0
12.4
3.0
4.3
2
3
6
5
6
4
7
8
6
8
5
17
2
6
4
4
4
7
3
3
Average Duration
of Each
Ammonite
Biozone (m.y.)
2.00
1.03
1.15
1.32
1.23
1.00
0.56
0.38
0.58
0.70
0.96
0.31
2.65
1.05
0.98
1.25
3.25
1.77
2.00
1.43
17
The output from the phylogenetic analysis was compared and combined with the
stratigraphic data from McGowan and Motani (2003) to form an evolutionary tree for both the
genus-level analysis and species-level analysis. When combining a cladogram and stratigraphic
data to create an evolutionary tree, there are two typical ways of doing this, coined X-trees and
A-trees. X-trees compare the cladogram to the fossil record, combining the branching order of
the cladogram and the stratigraphic range of the taxa to produce the new tree (Smith, 1994). In
A-trees, taxa are taken from the cladogram and placed as direct ancestors to each other, implying
that ancestor-descendant relationships can be determined (Smith, 1994). X-trees are used most
often because they tend to retain the most detail (Smith, 1994). By making an X-tree, it is
possible to determine whether the cladogram is stratigraphically consistent. An X-tree was
therefore constructed for the derived ichthyosaurs included in this study.
The gap excess ratio (GER) (Willis, 1999) is a comparison of the duration of the ghost
lineages required by a cladogram to the best and worst-case scenarios for gaps found in the
record. The equation for the gap excess ratio is defined as:
(Eqn. 1) GER = 1 −
∑ MIG − G
min
G max − G min
where MIG (minimum implied gap) is the length of the ghost ranges present based on a
particular cladogram (Appendix D), Gmin is the minimum possible sum of ghost ranges or the
sum of distances between consecutive first appearance datums (FADs) and the Gmax is the
maximum possible sum of ghost ranges or the sum of distances from the first FAD to all of the
other FADs (Willis 1999) (Hammer and Harper, 2006) (Appendix E). The closer the GER value
is to 1, the better supported the cladogram is.
The Relative Completeness Index (RCI) (Benton and Storrs, 1994) is defined as:
18
⎛ ∑ MIG ⎞
⎟
(Eqn. 2) RCI = 100⎜1 −
⎜
⎟
SRL
∑
⎝
⎠
where SRL is the duration of the observed ranges and MIG is defined as above (Benton and
Storrs, 1994). RCI is interpreted such that the closer RCI is to 100 (that is, the smaller the MIG),
the better the completeness of the record. The RCI normally ranges between 0 and 100, but can
sometimes become negative (Hammer and Harper, 2006). This index is a more direct measure of
the fossil record and adds the aspect of time into the equation (Hammer and Harper, 2006).
The SCI (Huelsenbeck, 1994) analysis is similar to RCI, but does not use time. The SCI
is the proportion of stratigraphically consistent nodes on the cladogram. A node connecting two
taxa is stratigraphically consistent if the stratigraphically older taxon’s first occurrence is at the
same age or older than its sister taxon (Hammer and Harper, 2006). The resulting value for SCI
ranges from zero to one, with values closer to one indicating a more stratigraphically consistent
tree (Hammer and Harper, 2006).
Institutional Abbreviations: ROM, Royal Ontario Museum, Toronto; UCMP
University of California Museum of Paleontology, Berkeley.
19
RESULTS
Phylogenetic Analysis
PAUP Cladograms
I conducted two separate phylogenetic analyses, one using Motani’s (1998b) original
genus-level dataset to determine which characters were supporting his clades, and one with an
expanded dataset at the species level for the derived ichthyosaurs only. When I re-ran Motani’s
(1999b) data, I found 13 most parsimonious trees with 228 steps, which is similar to Motani’s
(1999b) findings of 12 trees and 254 steps (Consistency Index (C.I.)=0.6184, Rescaled
Consistency Index (R.C.)= 0.5202). I attribute the differences in our results to my decision not to
force certain genera to be the outgroup. I then used one of the 13 trees to compile a list of where
each character state change occurred on the tree (Figure 6). The major characters that define all
the derived ichthyosaurs as a clade (node 37) are the presence of a reduced peripheral shaft of the
radius, loss of an antero-medial iliac prominence, and presence medially of ischium-pubis fusion
in adults. The characters that define the Eurhinosauria clade (node 38) are loss of manual
accessory digit VI and a widely separated tibia and fibula. The Eurhinosauria clade includes the
genera Leptonectes, Excalibosaurus and Eurhinosaurus. The Thunnosauria clade (node 45) that
was present in Motani’s (1999b) study is defined by four character state changes that include a
widely open anterior process in the right and left parietals, presence of a manual pisiform, a
forelimb twice as long as hindlimb, and an ischium-pubis fusion present both medially and
laterally. The Thunnosauria clade includes all the genera from Stenopterygius forward on Figure
6. The characters that define Ophthalmosauria (node 49) consist of the absence or extreme
reduction of the basioccipital peg, the basioccipital extracondylar area having a narrow band of
20
concavity, the angular lateral exposure being at least as high and anteriorly placed as the
surangular exposure, the ridge of the humerus being plate-like, and the presence of the manual
anterior sesamoid e and the digit distal to it. The clade Ophthalmosauria includes all the genera
from Brachypterygius forward on Figure 6.
Figure 6. One tree from Motani’s (1999b) data set that shows where the character state changes
occur. The bold face numbers indicate node numbers while the numbers in parentheses
indicate the number of character state changes at that node. A list of the actual
character state changes can be found in Appendix F. Compare to Figure 4, showing
Motani’s (1999b) consensus tree.
21
When the second, species level-analysis for the derived ichthyosaurs was run, PAUP*
(Swofford, 2001) produced three most parsimonious trees with 196 steps (C.I. = 0.5918, R.C.
=0.3317). The strict consensus tree shows that the only variation among these trees is one
polytomy involving three ophthalmosaurian species (Figure 7). The results of the bootstrap and
jackknife analyses can be seen in Figure 8. In these analyses, only two clades are kept and only
one is significant. The significant clade is the one that is retained 71% of the time, meaning that
there is a little more than a 95% chance that the clade is real (Hillis and Bull, 1993). This clade
included the species of Ichthyosaurus, Stenopterygius, and Temnodontosaurus and two of the
Leptonectes species, Leptonectes tenuirostris and Leptonectes moorei. This clade correlates to
node 15 on the tree in Figure 9 and is supported by 13 character state changes.
Figure 7. Strict consensus tree from species-based analysis showing the one polytomy present.
22
Figure 8. Bootstrap and jackknife support for subclades. The bold numbers are from the
bootstrap analysis, while the other number is from the jackknife analysis. Jackknife
analysis did not support the subclade including Ophthal. discus, Brachy. extremus, and
Caypull. bonaparte.
Temnodontosaurus trigonodon was pulled up the tree and the clade Ophthalmosauria was
pulled down the tree relative to Motani’s (1999b) phylogeny (compare Figures 6 and 7). The
polytomy also separates the two Ophthalmosaurus species, indicating that Ophthalmosaurus
icenicus may not belong in the previously defined Ophthalmosauria clade (Figure 9). There are
ten characteristics that separate Ophthalmosaurus icenicus from the rest of the previously
defined Ophthalmosauria clade. These ten characters include the presence of a nasal and external
23
naris contact, the presence of a nasal and parietal contact lateral to the frontal, a trilunate shaped
postorbital, a short anterior process of the maxilla in lateral view, the distal radial articular facet
on the humerus is terminal and larger than the ulnar facet, the anterior flange on the humerus is
absent, the radius is longer than wide, the thyroid fenestra is absent, the tibia peripheral ‘shaft’ is
absent, and the postorbital is narrow. None of these specific characteristics were part of the
definition of the clade Ophthalmosauria (node 49) in Motani’s (1999b) analysis. The rest of the
previously defined clade is grouped together by the following nine characteristics (which include
the characters defining this clade in Motani’s previous study): an absent or extremely reduced
bassioccipital peg, bassioccipital extracondylar area reduced to a narrow band of concavity, the
angular lateral exposure is at least as high and anterior as surangular exposure, the distal and
proximal ends of the humerus exclusive of anterior flange are nearly equal, a plate-like ridge on
humerus, the presence of an antero-distal facet for sesamoid on the humerus, the presence of a
manual anterior sesamoid e and the digit distal to it, ischium-pubis fusion present medially and
laterally, and the peripheral ‘shaft’ of the tibia is absent.
This analysis also shifted the previously defined clade of Eurhinosauria from a
monophyletic clade to a paraphyletic group. Two of the Leptonectes species, Leptonectes
tenuirostris and Leptonectes moorei, are seen as more derived in this new analysis (Figure 9).
Leptonectes moorei is defined by a radius that is longer than wide, a complete or nearly complete
ulna peripheral ‘shaft’, a mc 1 that is not ossified, and the absence of a manual digit S4-5. These
characteristics do not compare to those that defined the Eurhinosauria clade previously (loss of
manual accessory digit VI and a widely separate tibia and fibula). Leptonectes tenuirostris is
defined by the upper dental groove being present only anteriorly, presence of interdigital
24
separation, ischium-pubis fusion present medially and laterally, the atlantal pleuro centrum
separate from axis, and having two distinguishable sacral ribs.
Figure 9. Character state changes for species-level analysis. The bold face numbers indicate node
numbers while the numbers in parenthesis indicate the number of character state
changes at that node. A list of the actual character state changes can be seen in
Appendix G.
One species of Stenopterygius, S. megacephalus, is separated from the rest of the species
in this genus. Stenopterygius megacephalus is defined by an anterior notch on the radiale present
preaxially, and by the metacarpal 5 not being ossified. Stenopterygius megacephalus is mixed in
with two Leptonectes species and the Ichthyosaurus genus. Motani’s (1999b) analysis defines the
genus Stenopterygius by the presence of nasal/parietal contact lateral to frontal and the presence
25
of manual digit S4-5. In contrast, this analysis found that neither of these characteristics define
Stenopterygius megacephalus, although it does have manual digit S4-5.
Temnodontosaurus trigonodon and Stenopterygius quadrisissus are grouped together in
the species-level analysis. These species are grouped together by the following characteristics:
the width of the humerus exclusive of the anterior flange being nearly squarish, a complete or
nearly complete radius contiguous ‘shaft’ and ulna peripheral ‘shaft’, and a presence of the
metacarpal I peripheral ‘shaft’. Temnodontosaurus trigonodon is defined by the ulna peripheral
shaft being a notch or largely reduced and by the metacarpal V peripheral ‘shaft’ being complete
or nearly complete. Stenopterygius quadrisissus is defined by a complete radius peripheral
‘shaft’, the metacarpal I peripheral ‘shaft’ not being ossified, and the absence of the metacarpal
III ‘shaft”. The two character state changes that group Temnodontosaurus trigonodon and
Stenopterygius quadrisissus together also place Stenopterygius quadrisissus as its own species.
The width of humerus is a reversal while the metacarpal I peripheral ‘shaft’ is a different state,
meaning that only two characteristics really define Stenopterygius quadrisissus and three group
Temnodontosaurus trigonodon and Stenopterygius quadrisissus together. None of these species
are defined by the same characteristics set by Motani’s (1999b) analysis. Stenopterygius
cuneiceps is the only species with the presence of the nasal/parietal contact lateral to frontal and
none have the presence of the manual S4-5 digit. There are also two characters that seem unique
to Temnodontosaurus trigonodon and one other species. For the ulna contiguous ‘shaft’,
Temnodontosaurus trigonodon and Stenopterygius cuneiceps are the only ones with the character
state of notch or largely reduced, and for character metacarpal V peripheral ‘shaft’ the only other
species to have a complete or nearly complete character state is sometimes Ichthyosaurus
26
conybeari. These more derived characters could be the reason that this species was pulled up the
tree.
When looking at the new cladogram associated with the species-level analysis, four
previously defined taxa fall apart: Leptonectes, Stenopterygius, and the groups Eurhinosauria and
Ophthalmosauria. With these clades falling apart, Motani’s (1999b) argument that
Stenopterygius and Ophthalmosauria could be sister taxa by adding one extra step to the
cladogram falls apart as well. With the new cladogram, to make the two clades sister taxa, more
than one step will need to be added to the tree, and, in fact, these groups no longer exist as true
clades in the new cladogram.
Evolutionary Tree
An X-tree was created for the species-level analysis by combining the cladogram and the
stratigraphic record of the species present in the cladogram (Figure 10). The general stratigraphic
range and geographic location of each species in my analysis are indicated in Figure 11. For the
tree presented in Figure 9 to work, there must be a period of rapid evolution prior to the Upper
Triassic that produced the major lineages. It is possible that the genera of Stenopterygius and
Leptonectes are stratigraphically defined. This means that, for instance, if there were a specimen
found in the Toarcian that did not look like Suevoleviathan or Eurhinosaurus, it would be
automatically classified as Stenopterygius, and given a new species name. Hence, the taxonomic
definitions of these two genera need to be evaluated and revised. The geographic locations of
these ichthyosaurs did not seem to expand until the Atlantic started to form in the Late Jurassic
(Gasparini and Fernández, 1997). The species that were present in the Late Triassic and Early
Jurassic are only found in England, France and/or Germany while towards the end of the
Jurassic, the geographical range of these ichthyosaurs expands into Russia and North and South
27
America, as indicated by the Upper Jurassic American species Ophthalmosaurus discus and
Caypullisaurus bonaparte, and Russian Ophthalmosaurus icenicus and Brachypterygius
extremus. Note that only members of the Ophthalmosauria (sensu Motani, 1999b) participate in
this biogeographic expansion.
Figure 10. Phylogenetic tree for species. The X-tree for my species-level analysis. Stage
names and durations can be seen in Table 1.
28
Figure 11. Consensus tree showing the stratigraphic interval during which each of the species is
present and its common geographic locations. L - Lower, M - Middle, U - Upper,
Tri - Triassic, Jur - Jurassic, Cret - Cretaceous.
29
Phylogenetic vs. Stratigraphic Parsimony
When calculating the Gap Excess Ratio (GER) (Willis, 1999), Relative Completeness
Index (RCI) (Benton and Storrs, 1994) and Stratigraphic Congruency Index (SCI) (Huelsenbeck,
1994), the X-tree (Figure 10) and the durations from Table 1 were used. The Gap Excess Ratio
(GER) (Willis, 1999) was calculated using Equation (1) for Motani’s (1999b) genus-level
analysis as well as my analysis done at the species level. The GER for Motani is 0.799 and for
my species analysis is 0.955. In constructing the X-tree, ghost taxa needed to be added below
the earliest known stratigraphic occurrences of included species. When calculating the Minimum
Implied Gap (MIG) for the genus analysis, I decided to omit the length of these ghost taxa,
because there was no way to tell how long these ghost taxa would be. The assumption is that
they would be minimal when compared to the rest of the stratigraphic gaps, and likely confined
to the Upper Triassic. The GER values show that my species level analysis has better
stratigraphic resolution, even with the more derived ichthyosaurs being pulled down the tree,
than Motani’s genus-level analysis.
The Relative Completeness Index (RCI; see Equation (2)) (Benton and Storrs, 1994) was
also calculated for Motani’s (1999b) analysis as well as my species-based analysis. The RCI for
Motani’s analysis is 1.87 and for my species analysis is 7.79. These lower numbers imply that
the fossil record for ichthyosaurs is very poor (length of gaps is nearly equal to the observed
durations) and is even worse on the genus level than the species level, which is surprising.
The Stratigraphic Congruency Index (SCI) (Huelsenbeck, 1994) was calculated only for
my species-based analysis, as it is not meaningful to compare genus-level and species-level
cladograms in this way. The SCI was 9/17 or 0.529. For the node to be considered
stratigraphically consistent, had to be consistent with the stratigraphic record as well as
30
consistent with the taxon next to it on the tree. This value shows us that about half of the
cladogram nodes are consistent with the stratigraphic record. The species that are causing the
main problems for the SCI are those of the previously defined Ophthalmosauria clade. The
Ophthalmosaurians now have an even longer ghost lineage than before. Pulling
Temnodontosaurus trigonodon up the tree actually helped with the stratigraphic debt.
Radiation of the Ophthalmosauria
The polytomy associated with the three species of Ophthalmosauria is potentially due to a
radiation caused by morphological innovation, although the dataset does include numerous
unknown character states for one or more of these three species. Five characters used in Motani’s
(1999b) analysis seemed to be potential morphological innovations based upon a change in
character state defining the Ophthalmosauria. The characters were identified as those that unite
the three taxa involved in the polytomy. These characteristics include: (1) the change from the
distal end of the humerus being wider to the distal and proximal ends being nearly equal
[55(1Æ0)], (2) the ridge on the humerus changing from not plate-like to plate-like [56(0Æ2)],
(3) the anterio-distal facet on the humerus developing [57(0Æ1)], (4) the peripheral ‘shaft’ of the
radius changing from a notch or largely reduced to entirely absent [59(1Æ2)], and (5) the
appearance of a manual anterior sesamoid e and the digit distal to it[75(0Æ1)]. For two of these
characters (2 and 4), the change is unique only to the Ophthalmosauria. It is not clear how the
ridge on the radius could have contributed to the radiation of these species, but the appearance of
the sesamoid e bone could have allowed for greater flexibility of the forefin, which could have
allowed for faster, more agile swimming. Because there are only two characters that change
within the Ophthalmosauria, it appears that anatomical innovations were not the sole cause of the
radiation.
31
DISCUSSION
The major difference between Motani’s (1999b) study and my current study is that
Motanis’(1999) study was performed at the genus level, while this analysis is at the species
level. I also truncated the dataset by focusing only on the more derived species. When you break
up an analysis, most of the time the dataset ends up with more unknown character states in it due
to the lack of multiple specimens for each species. When conducting an analysis such as this on
the genus level, unknown characters from one species can be filled in with the known characters
from another. This pooling of data from multiple species, however, can cause problems when
different species show different character states.
In the new species-level analysis, many of the previously defined taxa fell apart and were
no longer grouped together. These taxa include Leptonectes, Stenopterygius, and the groups
Eurhinosauria and Ophthalmosauria. This is a problem that needs to be looked at to see if these
species were identified properly. The genera of Leptonectes and Stenopterygius may be
stratigraphically defined. The groups of Ophthalmosauria (sensu Motani, 1999b) were also
pulled down the tree, and created larger stratigraphic debt in being placed there. One potential
explanation for the placement is that there were enough reversals in these species that when the
more primitive species were taken out, the ophthalmosaurians were interpreted as more primitive
than they actually are. To determine this, the character states of the more primative ichthyosaurs
need to be reanalyzed in a future report.
I feel that to further expand the species-level study, more specimens need to be added to
the species level analysis, especially including species from the youngest ophthalmosaurian
genus Platypterygius. I could not find good pictures of sufficient quality in the literature to
properly code characters for this genus. This expansion along with more specimens found and
32
added to the existing stratigraphic record of each species will help to improve upon my results.
Another way to help improve these results will be to define more characters that will specifically
help separate the more derived species from each other, as opposed to just the genera. Many of
these characters were good for separating ichthyosaurs on the genus level; in the species level
analysis, however, 52 uninformative characters were found. This large number of uninformative
characters is to be expected when leaving out most of the taxa used in the original study. Some
of these characters may be more useful if more specimens are found completely or almost
completely articulated and not just preserved or prepared in dorsal view.
In my species level analysis, I found that there is no way to determine whether placing
Stenopterygius as a sister group to Ophthalmosauria is more parsimonious because the
Ophthalmosauria clade falls apart in the species-level analysis. Making this change would no
longer be a small shuffle, as implied by Motani’s (1999b) analysis.
When comparing the new species-level cladogram to the stratigraphic record, the tree
was not highly supported, but the stratigraphic problems seemed to be caused by only a few
groups, specifically the ophthalmosaurian taxa and Eurhinosaurus longirostris, Leptonectes
solei, and Excalibosaurus costini. These are the groups that needed to have ghost lineages added
to them and in Equations (1) and (2), and the SCI calculations used. A potential explanation for
this is the fact that some of the ophthalmosaurian taxa are found in places outside of Europe and
may not be as well sampled. This is also coupled with the fact that these more derived
ichthyosaurs could have been living in different environments from the previous taxa and may
not be preserved as often. Most of the specimens I looked at were preserved in shales that came
from deep water and not as many sandstones and no limestones from shallow water. There also
33
may not be many rocks of that age and location being formed at that time, meaning that even
though these ichthyosaurs may have been living in this area, there is no evidence of it.
The widening of the Atlantic did not seem to relate to the polytomies from Motani’s
(1999b) study in the Late Triassic, but did affect the new radiation that appeared in the specieslevel analysis, in the Upper Jurassic. The North and South Atlantic started to for during the
Middle to Late Jurassic. The geographic range of the derived ichthyosaurs did not seem to
expand until the Late Jurassic and into the Early Cretaceous, right after these new environments
opened up. There are problems when examining geographic ranges of marine organisms,
including taphonomic problems. When evaluating the geographic range of these organisms,
because they were marine reptiles, you must take into account the possibility of taphonomic drift.
When a large swimming organism dies in the ocean and is decomposing, it tends to fill with gas
and can sometimes float miles away from where it was really living. Many of the species are
found in the Northwest Tethyan area before this radiation occurs, and this is also where you can
find lots of good specimens. The Tethyan (Europe) area seems to have been thoroughly sampled
and has fewer problems in this analysis because of this. To see if geographic expansion was
actually happening with ichthyosaurs during this time, we should look for specimens in the
potential pathways they could have taken. Some of this has been done in previous studies, but
more can still be done. Looking at other marine organisms with a higher preservation rate, like
ammonites or other invertebrates, could also help to show the potential biogeographic pathways
of ichthyosaurs.
I feel the morphological innovation may have also contributed, but was not the sole cause
of this radiation of the more derived ichthyosaurs to occur. The opening of the Atlantic, as
discussed previously, seems to have contributed to the radiation of the more derived ichthyosaurs
34
by creating new habitats for them to live in, but they needed a way to get into and thrive in these
new environments. There is a characteristic that is not used in this cladistic analysis that could be
an important morphological innovation, eye size. Ophthalmosaurus is known for its large eyes
and would have helped it to see it prey easier and probably at deeper depths. This is a
characteristic that should be looked at in future analyses.
35
SUMMARY AND CONCLUSIONS
The main objectives of this study were to conduct a more detailed phylogenetic analysis
of the more derived ichthyosaurs to answer two questions. The first problem was to determine if
a long ghost lineage, or placing Stenopterygius and a sister group to Ophthalmosauria was more
parsimonious. The second was to determine if the polytomies present in Motani’s (1999b)
analysis were due to phylogenetic problems such as many unknown characters, due to a radiation
due to the biogeographic expansion of ichthyosaurs during the breaking apart of Pangea, the
evolution of morphological innovation, or a combination of the above.
My species level analysis produced three main differences from that of Motani (1999b).
The major difference is that a group of more derived ichthyosaurs (Ophthalmosauria), according
to Motani’s (1999b) tree, were pulled down the tree. Three of the taxa from the Ophthalmosauria
formed a polytomy, and include Ophthalmosaurus discus, Brachyopterygius extremus, and
Caypullisaurus Bonaparte. The polytomies that were present in Motani’s (1999b) study were no
longer present. The species of the genus Leptonectes were separated from each other. The one
species in the genus Temnodontosaurus was pulled up the tree. Stenopterygius megacephalus is
separated from the rest of the genus in the species-level analysis as well. I feel that these species
need to be further examined to see if they are placed in the right genus. Ophthalmosaurus
icenicus is not grouped with the rest of the Ophthalmosaurians so either Ophthalmosaurus
icenicus or Ophthalmosaurus discus should be looked at again to see if they are placed in the
correct genus.
The previously defined clades of Ophthalmosauria (Motani, 1999b), Stenopterygius,
Leptonectes and Eurhinosauria fell apart in my species-level analysis. The species that would be
in the clade of Ophthalmosauria were also pulled down the cladogram and now have an even
36
longer ghost lineage to Stenopterygius, making the situation more complicated. It would not
longer be as simple as adding one extra step to the cladogram.
Through my re-analysis of Motani’s (1999b) study and my own species level analysis, I
have determined that the polytomies that were present in the genus level analysis can be cleared
up when more characters are added and the analysis broken down by species. The new polytomy
that is formed by the three taxa of ophthalmosaurians, may be due to a radiation enabled by the
opening of the North Atlantic during the same time these taxa were expanding their geographical
range. There are three characteristics that helped contribute to the geographic expansion of these
species and are the ridge on the humerus being plate-like, the presence of the manual anterior
sesamoid e and the digit distal to it, and the enlargement of the eyes relative to the body size.
37
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43
APPENDIX A. CHARACTER DESCRIPTIONS
Characters taken verbatim from Motani’s (1999b) analysis and Fernández’s (2007) analysis; the
boldfaced italicized text are my interpretations and additions. Characters 1-105 are taken from
Motani’s (1999b) analysis while 106-112 are taken from Fernández’s (2007) analysis.
1. Premaxilla posterior end – (0) concave and the dorsal process is longer than the ventral;
(1) pointed and scarcely entering the external naris; (2) concave and the ventral process is
longer than the dorsal. (Motani, 1999b)
2. Maxilla dorsal lamina – (0) absent; (1) present. [Maisch and Matzke, 1997: character 2
and 3(correlated)] (Motani, 1999b) I interpreted this character as something similar to
striations or fine layering of the bone, which was hard to see in pictures.
3. Maxilla/external naris contact – (0) present; (1) absent. [Maisch and Matzke, 1997
character 1] (Motani, 1999b)
4. External naris orientation – (0) dorso-lateral; (1) lateral, scarcely visible in dorsal view.
(Motani, 1999b) This character was difficult to code with many of the specimens in
lateral view, but sometimes could be coded.
5. Nasal/external naris contact – (0) absent; (1) present. (Motani, 1999b)
6. Wide contact between nasal/postfrontal – (0) absent; (1) present. [Maisch and Matzke,
1997 character 9] (Motani, 1999b)
7. Nasal/parietal contact lateral to frontal – (0) absent; (1) present. (Motani, 1999b)
8. Prefrontal/postfrontal contact – (0) absent, the dorsal margin of the orbit being formed by
the frontal; (1) present, eliminating the frontal from the dorsal margin of the orbit.
(Motani, 1999b)
9. Postfrontal postero-lateral process – (0) absent; (1) present, overlying the post orbital.
(Motani, 1999b)
10. Postfrontal participation in upper temporal fenestrate – (0) absent; (1) present. (Motani,
1999b)
11. Postorbital shape – (0) trilunate; (1) lunate, without posterior process. (Motani, 1999b)
12. Postorbital participation in upper temporal fenestra – (0) present; (1) absent. (Motani,
1999b)
13. Squamosal participation in upper temporal fenestra – (0) present; (1) absent; (2)
squamosal absent. (Motani, 1999b)
44
14. Anterior terrace of upper temporal fenestra – (0) absent; (1) present, but small, reaching
the posterior part of the frontal anteriorly; (2) present, and large reaching the nasal
anteriorly. (Motani, 1999b) I interpreted this as a ridge on the back portion of the upper
temporal fenestra that is located on the top of the skull, but it was, again, hard to see in
laterally preserved specimens.
15. Frontal widest position – (0) located posteriorly; (1) at the nasal suture. (Motani, 1999b)
16. Sagittal eminence – (0) absent; (1) present, but small involving only the parietal; (2)
present and large, involving the parietal, frontal, and nasal. (Motani, 1999b) I interpreted
this character as the presence or absence of a ridge down the middle of the skull.
17. Parietal ridge – (0) absent; (1) present. The parietal ridge (sensu McGowan, 1973) is a
feature that is only present in derived ichthyosaurs. (Motani, 1999b) I interpreted this as
a ridge present between the two upper temporal fenestrate that could be seen in dorsal
view.
18. Parietal supratemporal process – (0) short; (1) long. (Motani, 1999b)
19. Right and left parietals’ anterior process – (0) contacting each other anteriorly,
eliminating frontal from pineal foramen; (1) narrowly separated anteriorly, forming
parietal fork, and frontal dorsally visible along the pineal foramen; (2) widely open,
resulting in absence of clear fork. [Mazin, 1982; Calloway, 1989: character 2] (Motani,
1999b)
20. Supratemporal posterior slope – (0) absent; (1) present. (Motani, 1999b)
21. Supratemporal posterior ridge – (0) absent; (1) present. (Motani, 1999b)
22. Supratemporal ventral process – (0) absent; (1) present. (Motani, 1999b)
23. Jugal/quadrajugal dorsal contact – (0) absent; (1) present. (Motani, 1999b)
24. Jugal shape – (0) triradiate; (1) lunate, or J-shaped. (Motani, 1999b)
25. Cheek orientation – (0) mostly lateral; (1) largely posterior. (Motani, 1999b) It was
difficult to determine exactly where the check region was; but unfortunately all of the
specimens I saw were in lateral view and I, therefore, was unable to code this
characteristic.
26. Pterygoid, transverse flange – (0) antero-lateral; (1) posterio-lateral; (2) not well defined.
(Motani, 1999b)
27. Interpterygoidal vacuity – (0) present; (1) absent, or extremely reduced. [Maisch and
Matzke, 1997: character 22] (Motani, 1999b)
45
28. Ectopterygoid – (0) present; (1) absent. [Calloway, 1989 :char 9] (Motani, 1999b)
29. Basioccipital peg – (0) clearly present; (1) absent or extremely reduced. (Motani, 1999b)
30. Basioccipital extracondylar area – (0) wide; (1) reduced to a narrow band of concavity.
(Motani, 1999b)
31. Basioccipital condyle – (0) flat or slightly concave; (1) hemispherical. [Calloway, 1989:
character 1] (Motani, 1999b)
32. Angular lateral exposure – (0) extensive, at least as high and anteriorly as surangular
exposure; (1) much smaller than surangular exposure. (Motani, 1999b) This character is
referring to the angular bone present in the skull near the jaw joint and its exposure
compared to the surangular, which is found right next to the angular.
33. Overbite – (0) absent or slight; (1) clearly present. (Motani, 1999b)
34. Snout extremely slender – (0) no; (1) yes. (Motani, 1999b) This character seems very
subjective, and I looked at how Motani (1999b) coded different species and based my
interpretations off of his previous codings.
35. Replacement teeth – (0) appear outside the pulp cavity of the predecessor; (1) inside.
(Motani, 1999b) I was unable to see any replacement teeth in any specimen due to
preservation of specimens.
36. Plicidentine – (0) absent; (1) present. (Motani, 1999b) To be able to see this character, a
tooth must be broken or sawed across and I did not have access to any of those.
37. Tooth horizontal section – (0) circular; (1) disto-medially compressed; (2) laterally
compressed. (Motani, 1999b)
38. Posterior tooth crown – (0) conical; (1) rounded; (2) flat. (Motani, 1999b)
39. Tooth size relative to skull width – (0) normal (over 0.10); (1) small (below 0.05).
(Motani, 1999b)
40. Maxillary tooth row – (0) single; (1) multiple. (Motani, 1999b)
41. Upper dental groove – (0) present throughout jaw margin; (1) only present anteriorly; (2)
absent. (Motani, 1999b) I coded this character based on where the teeth were seen in
the jaw. Because many specimens were pictures, there was no way to tell if it was
actually a dental groove present or individual sockets for the teeth.
42. Lower dental groove – (0) present throughout jaw margin; (1) only present anteriorly; (2)
absent. (Motani, 1999b) See interpretation for char 41.
46
43. Bony fixation of teeth – (0) present; (1) absent. (Motani, 1999b)
44. Pterygoidal teeth – (0) present; (1) absent. (Motani, 1999b)
45. Interclavicle shape – (0) cruciform; (1) triangular; (2) T-shaped. (Motani, 1999b)
46. Scapula antero-dorsal margin – (0) fan-shaped; (1) emarginated; (2) straight. [Calloway,
1989: character 23] (Motani, 1999b)
47. Scapular blade shaft – (0) absent; (1) present at least proximally. (Motani, 1999b)
48. Scapular axis and glenoid facet orientations – (0) nearly parallel; (1) at 60 degrees or
more. (Motani, 1999b) I interpreted facets as worn down areas on the bone where
another bone would attach.
49. Coracoid facet on scapula – (0) scapula and coracoid fused; (1) absent; (2) equal or
smaller than glenoid facet of scapula; (3) twice as large as glenoid facet. (Motani, 1999b)
50. Ossified sternum – (0) absent; (1) present. (Motani, 1999b)
51. Ossified cleithrum – (0) present; (1) absent. (Motani, 1999b)
52. Humerus distal articular facets – (0) not terminal; (1) terminal, radial facet being larger
than ulnar facet; (2) terminal, two facets being nearly equal. (Motani, 1999b)
53. Humerus anterior flange – (0) absent; (1) present and complete; (2) present but reduced
proximally. [Calloway, 1989: character 29] (Motani, 1999b)
54. Humerus relative width exclusive of anterior flange – (0) much longer than wide; (1)
nearly squarish. [Calloway, 1989: character 28] (Motani, 1999b)
55. Humerus, distal and proximal ends, exclusive of anterior flange – (0) nearly equal; (1)
distal end wider than proximal end. (Motani, 1999b)
56. Ridge on humerus plate-like – (0) no; (1) yes. (Motani, 1999b)
57. Humerus antero-distal facet for sesamoid – (0) absent; (1) present. [Godefroit, 1993:
character 10] (Motani, 1999b) A sesamoid bone holds tendons away from the other
bones and can be found between the metatarsals and phalanges.
58. Propodial + epipodial versus manus length – (0) propodial + epipodial length longer; (1)
manus longer. (Motani, 1999b) I interpreted the propodial as the humerus/femur, the
epipodial as the radius and ulna/ tibia and fibia, and the manus as everything distal to
that.
47
59. Radius peripheral ‘shaft’ – (0) complete or nearly complete; (1) notch or largely reduced;
(2) absent. (Motani, 1999b). This character was hard to interpret, but I looked at how
Motani had coded the different genera and also took into account the idea that this was
talking about a shaft on the peripheral or closer towards the radius than the fin.
60. Radius contiguous ‘shaft’ – (0) complete or nearly complete; (1) notch or largely
reduced; (2) absent. (Motani, 1999b) Interpreted this similarly to char 59 but looked for
a shaft on the edge of the radius.
61. Radius L/W ratio – (0) longer than wide; (1) wider than long. (Motani, 1999b)
62. Ulna peripheral ‘shaft’ – (0) complete or nearly complete; (1) notch or largely reduced;
(2) absent. (Motani, 1999b) See interpretation for char 59.
63. Ulna contiguous ‘shaft’– (0) complete or nearly complete; (1) notch or largely reduced;
(2) absent. (Motani, 1999b) See interpretation for char 60.
64. Radius/ulna relative size – (0) nearly equal; (1) radius larger than ulna. (Motani, 1999b)
65. Radiale, anterior notch – (0) absent; (1) preaxially present. (Motani, 1999b) Looked for
actual notch in the radiale bone.
66. Ulnare/intermedium relative size – (0) ulnare larger than intermedium; (1) intermedium
larger than ulnare; (2) intermedium lost. (Motani, 1999b)
67. Manual pisiform – (0) present; (1) absent. (Motani, 1999b) The pisiform can be found in
the proximal row of the carpus, where the ulna joins the carpus and is considered a
sesamoid bone.
68. Mc I peripheral ‘shaft’ – (0) complete or nearly complete; (1) notch or largely reduced;
(2) absent; (3) mc 1 not ossified. (Motani, 1999b) See interpretation for char 59.
69. Mc III ‘shaft’ – (0) present; (1) absent. [Calloway, 1989: character 33] (Motani, 1999b)
70. Mc V peripheral ‘shaft’ – (0) complete or nearly complete; (1) absent; (2) mc 5 not
ossified. (Motani, 1999b) See interpretation for char 59.
71. Manual digit 2 distal elements peripheral ‘shaft’ – (0) complete; (1) largely reduced or
notch; (2) absent. (Motani, 1999b) See interpretation for char 59.
72. Manual accessory digit VI – (0) absent; (1) present. [Mazin, 1982: character 4] (Motani,
1999b)
73. Manual digit S4-5 – (0) absent; (1) present. (Motani, 1999b)
74. Manual centralia – (0) present; (1) absent. (Motani, 1999b)
48
75. Manual anterior sesamoid e, and the digit distal to it – (0) absent; (1) present. (Motani,
1999b) See interpretation for char 57.
76. More than one extra anterior digit – (0) absent; (1) present. (Motani, 1999b)
77. Maximum phalangeal count – (0) five or less; (1) seven or more. (Motani, 1999b)
78. Interdigital separation – (0) present; (1) absent. (Motani, 1999b)
79. Forelimb/hindlimb ratio – (0) nearly equal or hind limb longer; (1) forelimb longer but
less than twice as hindlimb; (2) forelimb longer twice as much as hindlimb. [Calloway,
1989: char 26; Godefroit, 1993: character 5] (Motani, 1999b)
80. Iliac blade shape – (0) with thick shaft; (1) plate-like; (2) narrow and styloidal.
[Calloway, 1989: character 24] (Motani, 1999b)
81. Iliac antero-medial prominence – (0) present; (1) absent. (Motani, 1999b)
82. Thyroid fenestra – (0) absent; (1) one median opening; (2) two openings, being medially
separated. (Motani, 1999b)
83. Ischium-pubis fusion in adults – (0) complete; (1) absent; (2) present only medially; (3)
present medially and laterally. [Mazin, 1982: character 13] (Motani, 1999b)
84. Pubis, obturator foramen – (0) completely enclosed in pubis; (1) mostly in pubis but open
on one side; (2) part of obturator fossa. [Callaway, 1989: character 25] (Motani, 1999b)
85. Pubis, styloidal or plate-like – (0) plate-like; (1) styloidal. (Motani, 1999b)
86. Pubis/ischium relative length – (0) nearly equal or ischium slightly larger than pubis; (1)
pubis twice as long as ischium. (Motani, 1999b)
87. Ischium, styloidal or plate-like – (0) plate-like; (1) styloidal. (Motani, 1999b)
88. Tibia and fibula – (0) in contact or closely placed with each other; (1) widely separated
from each other. (Motani, 1999b)
89. Pes digit 1 – (0) present; (1) absent. (Motani, 1999b)
90. Tibia L/W ratio – (0) longer than wide; (1) wider than long. (Motani, 1999b)
91. Tibia contiguous ‘shaft’ – (0) complete or nearly complete; (1) absent. (Motani, 1999b)
92. Tibia peripheral ‘shaft’ – (0) complete or nearly complete; (1) notch or largely reduced;
(2) absent. (Motani, 1999b)
49
93. Fibula posterior extent – (0) not fixed, fibula being mobile relative to femur; (1) much
posterior to femur; (2) about the same level as femur. (Motani, 1999b)
94. Atlantal pleuro centrum – (0) separate from axis; (1) fused with axis. (Motani, 1999b)
This is interpreted as the first vertebrae and its attachment to the axis, which was hard
to tell when specimens were preserved in lateral view.
95. Presacral count – (0) 30 or less; (1) between 40 and 50; (2) 55 or more. [Calloway, 1989:
character 13] (Motani, 1999b) (3) 31-39. This character state was added because I
found some specimens with presacral vertebrae between 31 and 39.
96. Caudal peak – (0) absent; (1) present. (Motani, 1999b)
97. Posterior dorsal centra shape – (0) cylindrical; (1) discoidal. [Calloway, 1989: character
19] (Motani, 1999b)
98. Mid-caudal centra height change – (0) gradual decrease; (1) increase; (2) sudden
decrease. (Motani, 1999b) This is interpreted as the change seen after the peak in the
tail.
99. Cervical bicipital rib facets – (0) absent; (1) present. [Calloway, 1989 character 14]
(Motani, 1999b)
100.Posterior-dorsal rib facets – (0) absent; (1) present at least near pelvic girdle. [Calloway,
1989:char 14] (Motani, 1999b)
101.Antero-dorsal rib facets – (0) confluent with anterior facet in at least some centra; (1) not
confluent in any of the centra. (Motani, 1999b)
102.Anterior dorsal neural spine – (0) normal; (1) narrow, high, and straight.
[Calloway,1989: character 16] (Motani, 1999b)
103.Neural spine anticlination in tail – (0) absent; (1) present. (Motani, 1999b)
104.Sacral ribs – (0) two, distinguishable; (1) not distinguishable. (Motani, 1999b)
105.Posterior gastralia – (0) present; (1) absent. (Motani, 1999b)
106.Anterior process of maxilla in lateral view – (0) long and broad; (1) long and narrow; (2)
short. (Fernández, 2007: character 1)
107.Descending process of the nasal on the posterior dorsal border of the nares – (0) absent;
(1) present. (Fernández, 2007: character 2)
50
108.Squamosal – (0) without posterior descending process; (1) squamosal with a posterior
descending process; (2) squamosal absent. (Fernández, 2007: character 4)
109.Postorbital – (0) broad; (1) narrow. (Fernández, 2007: character 7)
110.Humerus/intermedium contact – (0) absent; (1) present. (Fernández, 2007: character 16)
111.Location of the intermedium – (0) between radius and ulna; (1) distal to the ulna.
(Fernández, 2007: character 19)
112.More than one anterior accessory digit – (0) absent; (1) present. (Fernández, 2007:
character 21)
51
APPENDIX B. SPECIES DATA
Presented below is a compilation of all the species character state codes I collected through
museums and primary literature. The “?” represents unknown character states while “&” show
polymorphism of character states. See Appendix A for characters and character descriptions.
Species name
Suevoleviathan disinteger
Leptonectes tenuirostris
Leptonectes solei
Leptonectes moorei
Excalibosaurus costini
Eurhinosaurus longirostris
Temnodontosaurus trigonodon
Ichthyosaurus communis
Ichthyosaurus conybeari
Stenopterygius quadrisissus
Stenopterygius megacephalus
Stenopterygius megalorhinus
Stenopterygius macrophasma
Stenopterygius cuneiceps
Ophthalmosaurus icenicus
Ophthalmosaurus discus
Brachypterygius extremus
Caypullisaurus bonaparte
Char
1
2
?
2
2
?
2
?
0
2
2
?
?
2
1
2
2
2
?
Species name
Suevoleviathan disinteger
Leptonectes tenuirostris
Leptonectes solei
Leptonectes moorei
Excalibosaurus costini
Eurhinosaurus longirostris
Temnodontosaurus trigonodon
Ichthyosaurus communis
Ichthyosaurus conybeari
Stenopterygius quadrisissus
Stenopterygius megacephalus
Stenopterygius megalorhinus
Stenopterygius macrophasma
Stenopterygius cuneiceps
Ophthalmosaurus icenicus
Ophthalmosaurus discus
Brachypterygius extremus
Caypullisaurus bonaparte
14
0
?
0
2
0
0
?
?
0
?
?
?
1
?
?
0
0
?
2
3
4
0
?
0
2
0
0
?
1
?
1
?
?
?
?
?
0
0
0
?
0
?
2
?
0
?
1
0
0
?
?
0
0
1
1
?
?
1
1
1
2
1
1
?
0
1
1
?
?
?
?
?
1
1
1
15
1
?
?
2
?
?
?
0
1
?
?
?
0
?
?
1
?
?
16
1
?
?
2
?
0
?
?
?
?
?
?
?
?
?
0
?
?
17
1
?
1
2
?
1
?
1
?
?
?
?
1
?
?
1
?
?
5
6
0
1
1
?
0
?
2&1 2&0
0
?
0
?
?
?
1&0 1
0
0
1
1
?
?
?
?
1
0
1
0
1
?
0
1
1
?
?
?
18
0
?
0
2
?
0
?
?
?
?
?
?
?
?
?
0
?
?
19
1
?
?
2
?
?
?
2
?
?
?
?
?
?
?
2
?
?
20
1
?
1
2
?
1
?
1
?
?
?
?
?
?
?
1
?
?
7
8
9
10
11
12
13
?
?
?
2
?
0
?
?
1
0
?
?
0
1
1
0
?
?
1
?
1
2
1
1
?
1
0
1
?
?
1
1
?
1
1
?
1
?
1
2
1
1
?
?
1
1
?
?
1
1
?
1
1
?
1
1
1
2
?
1
?
1
1
?
?
?
1
?
?
1
?
?
1
1
1
2&0
1
1
?
1
1
1
?
?
1
1
0
1
1
1
1
1
1
2
1
1
?
1
1
?
?
?
1
?
1
1
1
?
?
?
?
2
?
?
?
2
?
1
?
?
1
?
?
1
?
?
21
?
?
?
2
?
?
?
1
?
?
?
?
?
?
?
1
?
?
22 23 24 25
?
1
1
0
?
?
1
1
?
?
1
1
2 2&1 2&1 2
?
?
1
1
?
1
1
1
?
?
?
?
?
?
1
?
?
1
1
?
?
1
1
0
?
?
?
?
?
?
?
?
?
1
0
?
?
1
0
?
?
1
1
?
1
1
1
0
?
1
?
0
?
?
?
?
26
?
?
?
2
?
?
?
?
?
?
?
?
?
?
1
2
?
?
27
?
0
0
2
?
?
?
?
?
?
?
?
?
?
0
0
?
?
28
?
?
?
2
?
?
?
?
?
?
?
?
?
?
1
1
?
?
52
29
Species name
?
Suevoleviathan disinteger
?
Leptonectes tenuirostris
?
Leptonectes solei
2
Leptonectes moorei
?
Excalibosaurus costini
?
Eurhinosaurus longirostris
Temnodontosaurus trigonodon ?
0
Ichthyosaurus communis
?
Ichthyosaurus conybeari
?
Stenopterygius quadrisissus
Stenopterygius megacephalus ?
?
Stenopterygius megalorhinus
Stenopterygius macrophasma ?
?
Stenopterygius cuneiceps
?
Ophthalmosaurus icenicus
1
Ophthalmosaurus discus
1
Brachypterygius extremus
?
Caypullisaurus bonaparte
42
Species name
0
Suevoleviathan disinteger
?
Leptonectes tenuirostris
0
Leptonectes solei
?
Leptonectes moorei
0
Excalibosaurus costini
0
Eurhinosaurus longirostris
Temnodontosaurus trigonodon ?
0
Ichthyosaurus communis
0
Ichthyosaurus conybeari
0
Stenopterygius quadrisissus
Stenopterygius megacephalus 0
0
Stenopterygius megalorhinus
0
Stenopterygius macrophasma
?
Stenopterygius cuneiceps
0
Ophthalmosaurus icenicus
0
Ophthalmosaurus discus
0
Brachypterygius extremus
?
Caypullisaurus bonaparte
30
?
?
0
2
?
0
?
?
?
?
?
?
?
?
?
1
1
?
43
?
?
1
?
1
1
?
?
?
?
?
?
?
?
?
1
1
?
31
?
?
1
2
?
1
?
?
?
?
?
?
?
?
?
1
1
?
44
?
?
1
?
1
1
?
?
?
?
?
?
?
?
?
1
1
?
32 33
1
0
?
0
1
0
2&0 2&0
1
1
1
1
?
?
0
0
0
0
?
0
?
0
1
0
?
0
0
0
?
?
0
0
0
0
0
?
45
?
?
2
?
?
2
?
?
?
2
?
?
?
?
?
2
?
2
34
0
1
1
1
1
1
?
0
1
1
1
0
1
0
?
0
0
0
46
2
0&2
2
2
2
2
?
0
?
0
?
?
0
?
2
2
?
2
35
?
?
?
?
?
?
?
?
?
?
?
?
?
?
?
1
?
?
47
1
1
1
1
1
1
?
?
?
1
?
?
1
?
1
1
?
1
36
1
?
1
?
1
1
?
?
?
?
?
?
?
?
?
1
1
?
48
0
?
0
?
0
0
?
?
?
?
?
?
?
?
?
0
?
0
37
0
?
0
?
0
0
?
?
?
?
?
?
?
?
?
0
0
?
38
0
?
0
?
0
0
?
?
?
?
?
?
?
?
?
0
0
?
49
3
?
3
?
3
3
?
?
?
?
?
?
?
?
?
3
?
3
50
0
?
0
?
0
0
?
?
?
?
?
?
?
?
?
0
?
?
39
0
?
1
?
1
1
?
?
?
?
?
?
?
?
?
?
0
?
51
1
?
1
?
1
1
?
0
?
?
?
?
?
?
1
1
?
?
40
?
?
0
?
0
0
?
?
?
?
?
0
?
?
0
0
0
?
52
2
2&1
2
2
2
2
2
2
2
2
2
2
2
2
1
2
2
2
41
?
1
0
?
0
0
?
0
0
0
0
0
1
?
0
0
0
?
53
2
0&2
2
0&2
2
2
2
2
2
2
?
0
?
2
0
2
2
2
53
54
55
Species name
0
1
Suevoleviathan disinteger
0
1&0
Leptonectes tenuirostris
0
0
Leptonectes solei
1&0 0&1
Leptonectes moorei
0
1
Excalibosaurus costini
0
1
Eurhinosaurus longirostris
1
Temnodontosaurus trigonodon 1
0&1
0
Ichthyosaurus communis
1
0
Ichthyosaurus conybeari
1
1
Stenopterygius quadrisissus
0
Stenopterygius megacephalus 0
1
1
Stenopterygius megalorhinus
0
1
Stenopterygius macrophasma
0
0
Stenopterygius cuneiceps
0
1
Ophthalmosaurus icenicus
0
0
Ophthalmosaurus discus
0
0
Brachypterygius extremus
0
0
Caypullisaurus bonaparte
66 67
Species name
1
1
Suevoleviathan disinteger
1
1
Leptonectes tenuirostris
1
1
Leptonectes solei
1
1
Leptonectes moorei
0
1
Excalibosaurus costini
0
0
Eurhinosaurus longirostris
?
Temnodontosaurus trigonodon 1
0
0
Ichthyosaurus communis
1
?
Ichthyosaurus conybeari
0&1 0&1
Stenopterygius quadrisissus
?
Stenopterygius megacephalus 1
0
?
Stenopterygius megalorhinus
?
Stenopterygius macrophasma 0
1
?
Stenopterygius cuneiceps
1
?
Ophthalmosaurus icenicus
1
0
Ophthalmosaurus discus
1
0
Brachypterygius extremus
1
1
Caypullisaurus bonaparte
56
0
?
0
0
0
0
0
0
0
0
?
0
?
0
0
1
1
1
68
3
3
3
3
3
3
0
1
1
3
1
1
1
1
3
3
3
3
57
0
?
0
?
0
0
0
0
0
?
0
0
?
?
?
1
0
1
58
59
60
61
62
63
1
2
2
1
2
2
1
1
1
0&1 0&1
0
1
1
1&2 0&1
2
1&2
1
0&1
0
0
0
0
1
1
2
1
2
2
1
2
2
1
2
2
1
1
0
1
0
1
0&1
1
1
1
1
0
1
0
0
1
1
0
1
0
0
1
0
0
1
1
0
1
1
0
1
0
1
1
1
0
1
1
1
1
1
0
1
0
1
0
1
1
1
2
2
0
2
2
1
2
2
1
2
2
1
2
2
1
2
2
1
2
2
1
2
2
69 70 71 72 73
1
1
2
1
1
1&0 1 2&0 1&0 0&1
1
1
2
0
0
1&0 1 2&0 0&1 0
1
2
2
0
0
1
1
2
0
0
0
0
0
1
0
0 1&0 1
1
1
0
0
0
1
1
1
1
0
1
0
0
2
0
1
1
0
1
1
1
0
0
1
0
1
0
0
1
1
1
0
1
1
2
1
1
1
1
2
1
0
1
1
2
1
?
1
1
2
1
0
74
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
75
0
0
0
0
0
0
?
?
?
1
?
?
?
?
?
1
1
1
64
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
76 77
0
1
0
0
0
1
0
0
0 1&0
0
1
0
0
0&1 1
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
0
1
1
1
65
1
0
0&1
0
0
0
1
0
0
0&1
1
0
1
1
0
0
0
0
78
1
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
54
79
Species name
1
Suevoleviathan disinteger
2
Leptonectes tenuirostris
2
Leptonectes solei
?
Leptonectes moorei
2
Excalibosaurus costini
1
Eurhinosaurus longirostris
Temnodontosaurus trigonodon 1
2
Ichthyosaurus communis
1
Ichthyosaurus conybeari
?
Stenopterygius quadrisissus
Stenopterygius megacephalus 2
1
Stenopterygius megalorhinus
Stenopterygius macrophasma 1&2
1
Stenopterygius cuneiceps
1
Ophthalmosaurus icenicus
2
Ophthalmosaurus discus
?
Brachypterygius extremus
?
Caypullisaurus bonaparte
80
1
?
2
?
2
2
2
?
?
?
?
?
?
0
1
2
?
?
92
Species name
1
Suevoleviathan disinteger
1&0
Leptonectes tenuirostris
1
Leptonectes solei
?
Leptonectes moorei
?
Excalibosaurus costini
1
Eurhinosaurus longirostris
Temnodontosaurus trigonodon ?
2&1
Ichthyosaurus communis
2
Ichthyosaurus conybeari
?
Stenopterygius quadrisissus
Stenopterygius megacephalus 1
0
Stenopterygius megalorhinus
1
Stenopterygius macrophasma
0
Stenopterygius cuneiceps
2
Ophthalmosaurus icenicus
2
Ophthalmosaurus discus
?
Brachypterygius extremus
?
Caypullisaurus bonaparte
93
2
2
2
?
1
2
?
2
2
?
2
2
2
2
2
2
?
?
81
0
?
1
?
?
1
?
?
?
?
?
?
?
?
?
1
?
?
94
?
0
1
?
?
1
?
1
?
1
?
?
?
?
?
1
?
1
82
2
1
2
?
?
2
1
?
?
?
?
?
?
?
0
2
?
?
95
1
1
2
?
1
1
1
1
3
1
1
3
2
3
1
1
?
3
83
1
3
2&3
?
?
1&2
2
?
?
?
?
?
?
?
?
3
?
?
96
1
?
1
?
1
1
?
1
1
1
1
1
1
1
1
1
?
?
84
2
?
2
?
2
2
1
?
?
?
?
?
?
?
?
2
?
?
97
1
0
1
0
1
1
?
1
?
0
?
0
?
1
?
1
1
1
85
1
0
0
?
?
1
0
?
?
?
?
?
?
?
?
1
?
?
86
0
0
1
?
?
0
0
?
?
?
?
?
?
?
?
0
?
?
98
2
?
2
?
?
2
?
2&0
0
2
0
0
2
2
2
2
?
?
87
1
0
1
?
0
1
0
?
?
?
?
?
?
?
?
1
?
?
99
1
?
1
?
?
1
?
?
?
1
?
?
?
?
?
1
?
?
88
0
1
1
?
1
1
?
0
0
?
0
0
0
1
0
0
?
?
100
1
?
1
?
1
1
?
?
?
1
?
?
?
?
?
1
?
1
89
1
0&1
1
?
0
1
?
0
0
?
0
0
0
0
1
1
?
?
101
1
?
1
?
?
1
?
?
?
1
?
?
?
?
?
1
?
?
90
1
0
1
?
0
1
?
1
1
?
0
1
1
1
1
1
?
?
102
0
?
0
?
?
0
?
0
1
0&1
1
0
0
0
0
0
?
0
91
1
1&0
1
?
?
1
?
1&0
1
?
1
1
1
1
1
1
?
?
103
?
?
?
?
?
?
?
1
?
1
1
0
0
1
1
?
?
?
55
104
Species name
1
Suevoleviathan disinteger
0
Leptonectes tenuirostris
1
Leptonectes solei
?
Leptonectes moorei
?
Excalibosaurus costini
1
Eurhinosaurus longirostris
Temnodontosaurus trigonodon ?
1
Ichthyosaurus communis
0
Ichthyosaurus conybeari
1
Stenopterygius quadrisissus
Stenopterygius megacephalus 1
1
Stenopterygius megalorhinus
0
Stenopterygius macrophasma
1
Stenopterygius cuneiceps
1
Ophthalmosaurus icenicus
1
Ophthalmosaurus discus
?
Brachypterygius extremus
?
Caypullisaurus bonaparte
105
1
?
?
?
?
?
?
1
0
?
1
1
1
1
1
?
?
?
106
?
1
?
1
?
?
?
2
1
1
?
?
?
0
2
2
1
1
107
?
1
?
1&0
?
?
?
0
0
?
?
?
1
?
1
1
?
0&1
108
?
?
?
1
?
?
?
2
?
?
?
?
0
?
1
1
?
0
109
0
1
?
1&0
?
?
?
1
1
1
?
?
0
0
1
1
0
0
110
0
0
?
1
0
?
0
0
0
0
1
0
0
0
0
0
1
0
111
0
0&1
?
1
1
?
0
0
0
0
1
0
0
0
0
0
0
1
112
0
0
?
0
0
?
0
0&1
0
0
0
0
0
0
0
0
0
1
56
APPENDIX C. UNINFORMATIVE CHARACTERS
A list of the parsimoniously uninformative characters from the species-level analysis.
Character
Number
4
8
9
10
12
17
18
19
20
21
22
23
26
27
28
31
33
35
36
37
38
40
42
43
44
45
47
48
49
50
51
52
53
58
64
74
76
Character Name
External naris orientation
Prefrontal/postfrontal contact
Postfrontal postero-lateral process
Postfrontal participation in UTF
Postorbital participation in UTF
Parietal ridge
Parietal supratemporal process
Right and left parietals’ anterior process
Supratemporal posterior slope
Supratemporal posterior ridge
Supratemporal ventral process
Jugal/quadratojugal dorsal contact
Pterygoid, transverse flange
Interpterygoidal vacuity
Ectopterygoid
Basioccipital condyle
Overbite
Replacement teeth
Plicidentine
Tooth horizontal section
Posterior tooth crown
Maxillary tooth row
Lower dental groove
Bony fixation of teeth
Pterygoidal teeth
Interclavical shape
Scapular blade shaft
Scapular axis and glenoid facet
orientations
Coracoid facet on scapula
Ossified sternum
Ossified cleithrum
Humerus distal articular facets
Humerus anterior flange
Propodial + epipodial versus manus
length
Radius/ulna relative size
Manual centralia
More than one extra anterior digit
Reason for Uninformative Status
Autapomorphies
Autapomorphies
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphies
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphies
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Constant
Autapomorphy
?
Autapomorphy
Constant
Constant
Autapomorphy
57
78
81
84
86
87
91
93
94
96
99
100
101
103
105
112
Interdigital separation
Iliac antero-medial prominence
Pubis, obturator foramen
Pubis/ischium relative length
Ischium, styloidal or plate-like
Tibia contiguous ‘shaft’
Fibula posterior extent
Atlantal pleuro centrum
Caudal peak
Cervical bicipital rib facet
Posterior-dorsal bicipital rib facet
Antero-dorsal rib facets
Neural spine anticlination in tail
Posterior gastralia
More than one anterior accessory digit
Autapomorphy
Autapomorphy
Autapomorphy
Autapomorphy
?
Autapomorphy/Constant
Autapomorphy
Autapomorphy
Constant
Constant
Constant
Constant
?
Autapomorphy
Autapomorphy
58
APPENDIX D. Calculating MIG for GER
A diagram showing how to calculate MIG for a portion of the tree for derived ichthyosaurs (first
five species). MIG is the minimum implied gap, or the length of the ghost ranges present based
on a particular cladogram (Hammer and Harper, 2006).
59
APPENDIX E. Calculating Gmin and Gmax for GER
A diagram showing how to calculate Gmin and Gmax for a portion of the tree for derived
ichthyosaurs (first five species). Gmin is the minimum possible sum of ghost ranges or the sum of
distances between consecutive first appearance datums (FADs). Gmax is the maximum possible
sum of ghost ranges or the sum of distances from the first FAD to all of the other FADs (Willis
1999, Hammer and Harper, 2006).
60
APPENDIX F. GENUS-LEVEL CHARACTER STATE CHANGES
Character state changes from the genus-level analysis using Motani’s (1999b) dataset, as seen in
Figure 6.
Node/Branch# Character: Character State Change
1
82:
83:
1Æ 0
1Æ0
2
2:
18:
24:
27:
51:
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
3
10:
26:
50:
0Æ1
0Æ1
0Æ1
4
55:
105:
0Æ1
0Æ1
5
50:
0Æ1
6
11:
20:
21:
32:
36:
37:
44:
49:
52:
53:
66:
74:
79:
80:
93:
95:
104:
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
7
1:
2:
4:
0Æ1
1Æ0
0Æ1
61
8:
18:
26:
27:
67:
0Æ1
1Æ0
0Æ2
1Æ0
0Æ1
8
9:
10:
14:
28:
68:
70:
78:
96:
103:
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
9
77:
0Æ1
10
39:
0Æ1
11
44:
79:
80:
104:
1Æ0
1Æ0
1Æ0
1Æ0
12
13:
22:
55:
58:
68:
81:
99:
100:
0Æ1
0Æ1
0Æ1
0Æ1
1Æ2
0Æ1
0Æ1
0Æ1
13
34:
42:
54:
60:
66:
84:
90:
95:
100:
0Æ1
0Æ2
0Æ1
0Æ1
1Æ2
0Æ1
0Æ1
1Æ2
1Æ0
14
40:
78:
1Æ2
1Æ2
62
15
4:
8:
12:
16:
19:
23:
26:
37:
39:
45:
62:
77:
97:
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ1
0Æ2
1Æ0
1Æ0
0Æ1
0Æ2
0Æ1
0Æ1
16
5:
6:
41:
46:
95:
100:
0Æ1
0Æ1
0Æ2
0Æ1
1Æ2
1Æ0
17
42:
62:
0Æ2
2Æ1
18
16:
54:
55:
1Æ0
0Æ1
1Æ0
19
17:
18:
31:
94:
0Æ1
1Æ0
0Æ1
0Æ1
20
1:
14:
16:
34:
86:
98:
102:
0Æ1
1Æ2
1Æ2
0Æ1
0Æ1
0Æ1
0Æ1
21
38:
39:
0Æ1
0Æ1
22
37:
0Æ2
63
41:
42:
72:
0Æ1
0Æ1
0Æ1
23
38:
40:
0Æ2
0Æ1
24
2:
15:
45:
49:
55:
59:
65:
67:
68:
69:
70:
71:
89:
101:
105:
1Æ0
0Æ1
1Æ2
1Æ2
1Æ0
0Æ1
0Æ1
0Æ1
2Æ3
0Æ1
1Æ2
0Æ1
0Æ1
0Æ1
0Æ1
25
13:
18:
41:
42:
54:
60:
66:
84:
90:
95:
100:
1Æ0
0Æ1
0Æ2
0Æ2
0Æ1
0Æ1
1Æ2
0Æ1
0Æ1
1Æ2
1Æ0
26
63:
101:
0Æ2
1Æ0
27
47:
48:
59:
64:
0Æ1
0Æ1
1Æ2
0Æ1
28
5:
60:
65:
0Æ1
1Æ0
1Æ0
64
29
49:
53:
70:
72:
84:
2Æ3
1Æ2
2Æ1
0Æ1
0Æ2
30
93:
1Æ2
31
54:
62:
80:
0Æ1
2Æ1
2Æ1
32
46:
47:
60:
61:
63:
82:
85:
92:
0Æ2
0Æ1
0Æ1
0Æ1
0Æ2
0Æ1
0Æ1
0Æ1
33
55:
59:
71:
0Æ1
1Æ2
1Æ2
34
65:
89:
102:
1Æ2
1Æ0
0Æ1
35
87:
90:
91:
93:
0Æ1
0Æ1
0Æ1
1Æ2
36
73:
80:
0Æ1
2Æ1
37
59:
81:
83:
2Æ1
0Æ1
1Æ2
38
72:
88:
1Æ0
0Æ1
39
7:
0Æ1
65
65:
70:
1Æ0
1Æ2
40
3:
16:
25:
34:
39:
1Æ0
1Æ0
0Æ1
0Æ1
0Æ1
41
55:
79:
1Æ0
1Æ2
42
70:
1Æ2
43
33:
0Æ1
44
59:
67:
1Æ2
1Æ0
45
19:
67:
79:
83:
1Æ2
1Æ0
1Æ2
2Æ3
46
7:
73:
0Æ1
0Æ1
47
13:
55:
59:
65:
92:
1Æ2
1Æ0
1Æ2
1Æ0
1Æ2
48
66:
83:
1Æ0
3Æ(1/2)
49
29:
30:
32:
56:
75:
0Æ1
0Æ1
1Æ0
0Æ1
0Æ1
50
57:
0Æ1
51
13:
16:
2Æ1
1Æ0
66
52
7:
76:
0Æ1
0Æ1
53
67:
0Æ1
67
APPENDIX G. SPECIES-LEVEL CHARACTER STATE CHANGES
Character state changes from the species-level analysis, as seen in Figure 9.
Node/Branch#
1
Character:
16:
65:
Character State Change
0Æ1
0Æ1
2
5:
7:
11:
52:
53:
61:
82:
92:
106:
109:
0Æ1
0Æ1
1Æ0
2Æ1
2Æ0
1Æ0
2Æ0
1Æ2
1Æ2
0Æ1
3
19:
26:
73:
79:
80:
81:
83:
1Æ2
1Æ2
1Æ0
1Æ2
1Æ2
0Æ1
1Æ2
4
29:
30:
32:
55:
56:
57:
75:
83:
92:
0Æ1
0Æ1
1Æ0
1Æ0
0Æ1
0Æ1
0Æ1
2Æ3
1Æ2
5
106:
109:
1Æ2
0Æ1
6
67:
0Æ1
7
5:
57:
110:
0Æ1
1Æ0
0Æ1
68
8
76:
95:
108:
111:
112:
0Æ1
1Æ3
1Æ0
0Æ1
0Æ1
9
3:
15:
22:
25:
28:
34:
39:
72:
88:
109:
1Æ0
1Æ0
1Æ2
0Æ1
1Æ2
0Æ1
0Æ1
1Æ0
0Æ1
0Æ1
10
33:
66:
67:
79:
82:
0Æ1
1Æ0
1Æ0
2Æ1
2Æ0
11
16:
59:
85:
0Æ2
2Æ1
1Æ0
12
55:
86:
95:
1Æ0
0Æ1
1Æ2
13
18:
30:
31:
77:
82:
87:
89:
90:
0Æ2
0Æ2
1Æ2
1Æ0
2Æ1
1Æ0
1Æ0
1Æ0
14
33:
66:
70:
93:
111:
0Æ1
1Æ0
1Æ2
2Æ1
0Æ1
69
15
2:
5:
32:
46:
51:
60:
62:
63:
69:
71:
72:
84:
97:
0Æ1
0Æ1
1Æ0
2Æ0
1Æ0
2Æ1
2Æ1
2Æ0
1Æ0
2Æ0
0Æ1
2Æ1
1Æ0
16
25:
27:
68:
88:
90:
1Æ0
0Æ2
3Æ1
1Æ0
0Æ1
17
41:
78:
83:
94:
104:
0Æ1
1Æ0
2Æ3
1Æ0
1Æ0
18
7:
13:
25:
55:
73:
98:
107:
0Æ1
1Æ2
0Æ2
1Æ0
0Æ1
2Æ0
1Æ0
19
1:
3:
4:
34:
66:
67:
71:
77:
97:
106:
108:
2Æ0
0Æ1
1Æ0
1Æ0
1Æ0
1Æ0
0Æ1
0Æ1
0Æ1
1Æ2
1Æ2
70
20:
2:
6:
8:
15:
17:
20:
21:
29:
46:
60:
102:
1Æ2
1Æ0
1Æ0
0Æ1
1Æ2
1Æ2
1Æ2
0Æ2
0Æ2
1Æ0
0Æ1
21:
5:
54:
59:
70:
79:
92:
95:
104:
105:
1Æ0
0Æ1
1Æ0
1Æ0
2Æ1
1Æ2
1Æ3
1Æ0
1Æ0
22
3:
4:
7:
8:
9:
10:
11:
12:
14:
15:
90:
110:
111:
0Æ2
1Æ2
1Æ2
0Æ2
1Æ2
1Æ2
1Æ0
1Æ2
0Æ2
1Æ2
1Æ0
0Æ1
0Æ1
23
61:
62:
68:
73:
1Æ0
1Æ0
1Æ3
1Æ0
24
65:
70:
0Æ1
1Æ2
25
14:
0Æ1
71
65:
75:
79:
108:
0Æ1
0Æ1
2Æ1
1Æ0
26
54:
60:
62:
68:
0Æ1
1Æ0
1Æ0
1Æ0
27
63:
70:
0Æ1
1Æ0
28
59:
68:
69:
1Æ0
0Æ3
0Æ1
29
6:
24:
66:
80:
95:
103:
106:
109:
1Æ0
1Æ0
1Æ0
2Æ0
1Æ2
1Æ0
1Æ0
1Æ0
30
41:
104:
0Æ1
1Æ0
31
1:
7:
34:
59:
71:
92:
95:
2Æ1
0Æ1
1Æ0
1Æ0
0Æ1
1Æ0
2Æ3
32
32:
53:
54:
65:
98:
0Æ1
2Æ1
0Æ1
1Æ0
2Æ0
33
55:
61:
63:
1Æ0
1Æ0
0Æ1
72
66:
88:
97:
103:
0Æ1
0Æ1
0Æ1
0Æ1