Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
Chapter 13
Cambrian echinoderm diversity and palaeobiogeography
SAMUEL ZAMORA1*, BERTRAND LEFEBVRE2, J. JAVIER ÁLVARO3, SÉBASTIEN CLAUSEN4, OLAF ELICKI5,
OLDRICH FATKA6, PETER JELL7, ARTEM KOUCHINSKY8, JIH-PAI LIN9, ELISE NARDIN10, RONALD PARSLEY11,
SERGEI ROZHNOV12, JAMES SPRINKLE13, COLIN D. SUMRALL14, DANIEL VIZCAÏNO15 & ANDREW B. SMITH1
1
Department of Palaeontology, Natural History Museum, Cromwell Road, London SW7 5BD, UK
2
UMR CNRS 5276, Université Lyon 1 & ENS-Lyon, 69622 Villeurbanne, France
3
Centro de Astrobiologı́a (CSIC/INTA), Ctra. de Torrejón a Ajalvir km 4, 28850 Torrejón de Ardoz, Spain
4
Géosystèmes, UMR 8157 and 7207 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq, France
5
Geological Institute, Freiberg University, Bernhard-von-Cotta Street 2, 09599 Freiberg, Germany
6
Department of Geology and Palaeontology, Faculty of Science, Charles University, Albertov 6, Praha 2, 128 43 Czech Republic
7
Queensland Museum, PO Box 3300, South Brisbane, Queensland 4101, Australia
8
Department of Palaeozoology, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden
9
State Key Laboratory of Paleobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology,
Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, China
10
UMR CNRS-UPS-IRD 5563 Géosciences Environnement Toulouse, Observatoire Midi-Pyrénées, F-31400 Toulouse, France
11
Department of Earth and Environmental Sciences, Tulane University, New Orleans, LA 70118, USA
12
Paleontological Institute RAS, Profsoyuznaya St 123, 117997 Moscow, Russia
13
Department of Geological Sciences, Jackson School of Geosciences, University of Texas, Austin, TX 78712-0254, USA
14
Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, USA
15
7 rue J.-B. Chardin, Maquens, 11090 Carcassonne, France
*Corresponding author (e-mail: [email protected])
Abstract: The distribution of all known Cambrian echinoderm taxa, encompassing both articulated specimens and taxonomically diagnostic isolated ossicles, is documented for the first time. The database described by 2011 comprises 188 species recorded from 65 formations from around the world. Formations that have yielded articulated echinoderms are unequally distributed in space and time. Only
Laurentia and West Gondwana provide reasonably complete records at the resolution of Stage. The review of the biogeographical distributions of the eight major echinoderm clades shows that faunas from Laurentia and Northeast Gondwana (China and Korea) are distinct from those of West Gondwana and Southeast Gondwana (Australia); other regions are too poorly sampled to make firm
palaeobiogeographical statements. Analysis of alpha diversity (species per formation) shows that diversity rose initially to Cambrian
Stage 5, declined into Guzhangian and Paibian before returning to Stage 5 levels by the end of the Cambrian. This pattern is replicated
in Laurentia and West Gondwana. We show that taxonomically diagnostic ossicles found in isolation typically occur significantly earlier
than the first articulated specimens of the same taxa and provide important information on the first occurrence and palaeobiogeographical
distribution of key taxa, and of the phylum as a whole.
Supplementary material: Articulated Cambrian echinoderms and Isolated plates of Cambrian echinoderms are provided at: http://
www.geolsoc.org.uk/SUP18668
The Cambrian represents a crucial period in the evolution of
many groups of Metazoa, and echinoderms are no exception.
During this period, echinoderms made their first appearance in
the fossil record and underwent their initial diversification that
established many of the major lines of the later Palaeozoic. The
existence of putative Ediacaran (Late Neoproterozoic) echinoderms (i.e. Arkarua: Gehling 1987; David et al. 2000) remains
speculative and far from widely accepted. As a result, the oldest
undisputed members of the Phylum Echinodermata, based on
articulated specimens, are from Cambrian Stage 3 and represented
by helicoplacoids and edrioasteroids in Laurentia and by gogiid
blastozoans in Gondwana. Because of their sturdy calcitic skeleton, echinoderms have left a rich fossil record; however, complete
and articulated specimens are typically to be found associated with
very specific facies in ‘echinoderm Lagerstätten’ (Smith 1988).
Our knowledge of Cambrian echinoderm Lagerstätten has been
greatly improved in the last two decades, with many new occurrences reported from palaeogeographical areas where few if any
echinoderms had been previously documented, notably in East
Gondwana (e.g. China, Korea), West Gondwana (e.g. Morocco,
Spain and Wales), and Siberia.
Despite this improved knowledge, facies from which echinoderm remains have been reported remain unequally distributed
through time and space, and thus the fossil record of early echinoderms suffers from a strong sampling bias that could confound
the analysis of the Cambrian echinoderm palaeobiogeography.
Figure 13.1a tabulates the chronological distribution of the 65 formations known to have yielded 188 species of articulated or partially articulated Cambrian echinoderms. The distribution of
formations is clearly patchy, with only North America providing
an unbroken record of fossiliferous formations through the Cambrian. West Gondwana is the next best-sampled region, albeit
From: Harper, D. A. T. & Servais, T. (eds) 2013. Early Palaeozoic Biogeography and Palaeogeography.
Geological Society, London, Memoirs, 38, 157–171. http://dx.doi.org/10.1144/M38.13
# The Geological Society of London 2013. Publishing disclaimer: www.geolsoc.org.uk/pub_ethics
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
158
S. ZAMORA ET AL.
(a)
(b)
(d)
(c)
(e)
with European localities providing a more complete record than
North Africa. Particularly poorly sampled are Siberia, Baltica and
some Gondwanan regions, such as South America and the Arabian margin. While Siberia and South America are undoubtedly
poorly explored and undersampled, others, such as Baltica and
Avalonia, lie in geologically well-studied regions of the world;
the dearth of echinoderm-bearing formations in these two regions
probably reflects something other than simple sampling bias.
Taking all palaeocontinents together (Fig. 13.1b), it is clear that
echinoderm-bearing formations are much more common in Cambrian Stage 5 and Drumian, whereas they are particularly poorly
represented at the start of the Furongian. This must partially
reflect major retrogradational –progradational shifts over the
continental blocks (megacycles; Spencer & Demicco 2002, fig.
1). Comparing the pattern of fossil-bearing formations from the
two best-sampled regions (Laurentia and West Gondwana;
Fig. 13.1c), we see that a similar bias exists in both regions, but
with a better Furongian record in Laurentia. In western North
America this pattern is also reflected in a shift in echinoderm
bearing facies from fine-grained siliclastics to shelf stormdominated carbonates (Sumrall et al. 1997). Most notably, the
number of species recorded through this time interval shows a
strong correspondence to sampling patterns (Fig. 13.1d, e).
With these difficulties in mind, the aim of this collaborative
project is to produce the most up-to-date documentation and
analysis of the palaeobiogeographical distribution of Cambrian
echinoderms, drawing together all published and available unpublished data that are known to us. Furthermore, we have tried
to incorporate all sources of information up to June 2011,
Fig. 13.1. Analysis of Cambrian formations
that have yielded articulated echinoderms.
(a) Number of formations per stage plotted
for six biogeographical regions (Laurentia,
South America, Baltica, West Gondwana
(Morocco, Newfoundland and Gondwanan
Europe), Siberia and East Gondwana
(Australia, Middle East and Far East)).
(b) Global number of formations per stage.
(c) Number of formations plotted for
Laurentia and West Gondwana. (d) Global
number of articulated echinoderm species
known per stage. (e) Number of articulated
echinoderm species known from each
Cambrian stage in Laurentia and West
Gondwana.
focusing not just on articulated fossil occurrences, but also including the frequently overlooked record of isolated plates obtained
after limestone etching. Particular attention has been devoted
to establishing the palaeobiogeographical distribution of first
occurrences of the major echinoderm clades in the fossil record.
Palaeogeographical units and chronostratigraphical
nomenclature
As outlined in Álvaro et al. (2013), the tectonostratigraphical units
into which we place Cambrian echinoderms represent a mixture
of palaeogeographical and palaeobiogeographical areas. The
tectonostratigraphical units that we employ here are: Baltica, Laurentia (including Sonora, Mexico), the Siberian Platform, West
Gondwana [Avalonia, the Mediterranean region (from West to
East: Morocco, Ossa –Morena, Iberia, Montagne Noire, Sardinia,
Saxo-Thuringia and Bohemia) and its transition to the Arabian
margin (Jordan and Turkey)] and East Gondwana (Iran, South
China and Australia). For our biogeographical analyses of echinoderm distribution we arbitrarily separate West Gondwana into
North Africa and Europe, and the Arabian margin and East Gondwana into the Near East (Turkey and Iran), Far East (China and
Korea) and Australia.
Only the Terreneuvian and Furongian of the proposed four-fold
Series division of the Cambrian System have been defined by the
International Subcommission on Cambrian Stratigraphy and ratified by the International Union of Geological Sciences (Peng
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
et al. 2004; Landing et al. 2007; Peng & Babcock 2008). The two
series remaining to be defined are provisionally termed Cambrian
Series 2 and 3. A tentative global correlation chart is given
in Figure 13.2, summarizing the regional chronostratigraphical
nomenclature followed in this chapter.
Palaeogeographical distribution of Cambrian echinoderms
The supplementary material to this paper lists all reported echinoderm occurrences from the Cambrian, along with their age and distribution with reference to major palaeobiogeographical areas.
During the Cambrian, echinoderms diversified, giving rise to
eight major groups (Figs 13.3 & 13.4): (1) helicoplacoids; (2)
eocrinoids; (3) edrioasteroids; (4) rhombiferans; (5) cinctans; (6)
ctenocystoids; (7) solutans; and (8) stylophorans. This diversity
coincides with the Cambrian groups classically identified in the literature (e.g. Ubaghs 1971, 1975; Derstler 1981; Paul & Smith
1984; Smith 1988; Sprinkle 1992). However, there are several
notable differences from these earlier works. First, we now include
rhombiferans as members of the Cambrian biota, whereas traditionally they have not been reported before the Early Ordovician.
Several recent finds suggest that basal members of this group
appeared by Cambrian Series 3 (Ubaghs 1998; Zamora 2010;
Zamora & Smith 2012). Second, two problematic taxa, Echmatocrinus and Eldonia, are omitted here. The putative crinoid
affinities of Echmatocrinus remain controversial; this lightly skeletized fossil was originally described as a primitive Cambrian
crinoid (Sprinkle 1973), but later reinterpreted as an octocoral
(Ausich & Babcock 1998; Reich 2009). Sprinkle & Collins
(1998, 2011) compared these two interpretations, and argued that
a basal crinoid assignment is much more likely than an early octocoral assignment, but the discussion is still open. Several species of
Eldonia have been interpreted as pelagic sea cucumbers (Walcott
1911; Durham 1974; questionably by Sprinkle 1992), whereas
Paul & Smith (1984) and Reich (2005) strongly disagreed with
this assignment (Reich 2010). Ossicles of Holothuroidea from
middle and upper Cambrian strata were mentioned by Bell
159
(1948) and Mankiewicz (1992), but without description and distinct record and thus remain questionable (Reich 2010). Recently,
hemichordate affinities were proposed for Eldonia and allied forms
(Caron et al. 2010). Finally, echinoderm affinities have been
suggested for the vetulocystids from the Cambrian Series 2 Lagerstätte of Chengjiang, China (Shu et al. 2004, 2010). However,
these fossils lack plating and are probably better interpreted as
close relatives of vetulicolians and thus as possible stem group
deuterostomes (Smith 2004; Swalla & Smith 2008; Clausen
et al. 2010). Most of these problematic taxa are restricted to
single localities and horizons (Eldonia is an exception), so their
exclusion here makes little difference to our subsequent palaeobiogeographical analyses and discussion.
Each group of Cambrian echinoderms is reviewed separately
below, with comments on their palaeogeographical distribution.
Helicoplacoidea
Helicoplacoids are a relatively small clade of exclusively
Cambrian Series 2 echinoderms. They have a spirally plated,
spindle- to bulb-shaped theca (Fig. 13.3a) constructed from numerous rows of interambulacral plates and just three ambulacra
(Durham & Caster 1963; Sprinkle & Wilbur 2005). The mouth
is thought to be situated at mid-height on the lateral side, and
the anus at the distal pole (Derstler 1981; Paul & Smith 1984;
Sprinkle & Wilbur 2005; Smith 2008). Helicoplacoids probably
lived with one of the thecal poles (the one opposite the anus)
either inserted into relatively firm, stabilized substrates (Dornbos
2006) or attached to bioclasts on these substrates (Sprinkle &
Wilbur 2005).
The three currently valid genera of helicoplacoids, Helicoplacus, Polyplacus and Waucobella (Durham 1967; Wilbur 2006),
all come from Laurentia (western USA). A helicoplacoid specimen
was reported from central British Columbia, Canada (Durham
1993), but it is now missing (Wilbur 2006); other undescribed
material from here exists (Sprinkle, pers. obs. 2010). Helicoplacoids are also known in the Cambrian Series 2 of Sonora,
Mexico (Zamora & Clausen, pers. comm.).
Fig. 13.2. Correlation chart of the Cambrian showing the global chronostratigraphical series and stages compared with regional usage in major areas of the world;
modified from Peng et al. (2004), Landing et al. (2007) and Peng & Babcock (2008). *Siberian regional ‘horizons’ not yet officially erected for the Furongian.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
160
S. ZAMORA ET AL.
Fig. 13.3. Representative Cambrian
echinoderms. (a) Helicoplacus gilberti
(BMNH E27094) from the Cambrian
Series 2 of North America.
(b) Guizhoueocrinus yui (KW-08) from
Cambrian Series 2 of China. (c) Kinzercystis
durhami (MCZ 581) from Cambrian Series
2 of North America. (d) Cambroblastus
enubilatus (QMF17872) from the Furongian
of Australia. (e) Sinoeocrinus lui (GM
9-3-1382) from the Cambrian Series 3 of
China. (f) Protorophus hispanicus
(MPZ2009/1233) from the Cambrian
Series 3 of Spain. (g) Ubaghsicystis segurae
(MNCN-I-30849) from Cambrian Series 3
of Spain. (h) Velieuxicystis ornata (VCMN
523a) from the Furongian of France. (i)
Lichenoides priscus (BMNH E29346) from
the Cambrian Series 3 of Bohemia. ( j) New
stromatocystitid edrioasteroid (MPZ2007/
1890) from the Cambrian Series 3 of Spain.
(k) Kailidiscus chinensis (GM 2146) from
the Cambrian Series 3 of China. All
photographs with the exception of D are
taken from latex casts whitened with NH4Cl
sublimate. Abbreviations: BMNH, Natural
History Museum (UK); MCZ, Museum of
Comparative Zoology, Harvard University
(USA); QMF, Queensland Museum,
Brisbane (Australia); GM and KW, The
Paleontological Museum, Guizhou
University (China); MPZ, Museo
Paleontológico Universidad Zaragoza
(Spain); VCMN, Collection Vizcaino,
Carcassonne (France); USNM, US National
Museum (USA); PIW, Institut für
Paläontologie der
Julius-Maximilians-Universität Würzburg
(Germany); IGR, Institut de Géologie,
Université de Rennes (France); NMP,
Národnı́ Muzeum, Prague (Czech
Republic); MNCN, Museo Nacional
Ciencias Naturales Madrid (Spain); SNUP,
Seoul National University Palaeontology
(Korea); TX, Nonvertebrate Paleontology
Laboratory, University of Texas at Austin
(USA); MNHN, Museum National
d’Histoire Naturelle, Paris (France).
Of the eight Cambrian echinoderm groups, helicoplacoids are
the clade with both the shortest stratigraphical range (restricted
to Cambrian Stage 3) and the most restricted palaeobiogeographical distribution (western Laurentia).
Edrioasteroidea
Edrioasteroids are an extinct group of sessile forms with a globular
to discoidal theca lacking exothecal appendages (Fig. 13.3f, j, k).
They have five ambulacra arranged in a 2– 1–2 pattern around a
central mouth, with the anal pyramid situated orally between the
C and D ambulacra. Edrioasteroids first appeared in Cambrian
Stage 3 of Laurentia (Durham 1967). The oldest named species
is ‘Stromatocystites’ walcotti from Stage 4 of Newfoundland
(Schuchert 1919; Smith 1985; Zhao et al. 2010). Other occurrences
from the same stage that may be approximately coeval or slightly
younger are Stromatocystites reduncus and Edriodiscus primoticus
(Smith & Jell 1990) from Queensland and ?Stromatocystites sp.
from the Bilbilian of northern Spain (S. Zamora, pers. obs. 2006).
Like many other echinoderm groups, edrioasteroids were much
more diverse in Cambrian Series 3. Typical Stromatocystites-like
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
161
Fig. 13.4. Representative Cambrian
echinoderms. (a) Coleicarpus sprinklei
(USNM 423877) from the Cambrian
Series 3 of North America. (b) Ctenocystis
utahensis (BMNH E63150) from the
Cambrian Series 3 of North America.
(c) Lignanicystis barriosensis (MPZ2007/
776) from the Cambrian Series 3 of Spain.
(d) Trochocystites bohemicus (NMP 9066)
from the Cambrian Series 3 of Bohemia. (e)
Gyrocystis badulesensis (PIW92V6I) from
the Cambrian Series 3 of Spain. (f)
Undatacinctus undata (IGR 1033a) from
the Cambrian Series 3 of Morocco. (g)
Minervaecystis? sp. (1791TX4) from the
Furongian of North America. (h)
Lobocarpus vizcainoi (VCMN 656) from
the Furongian of France. (i) Ceratocystis
perneri (NMP.L.10392) from the Cambrian
Series 3 of Bohemia. (j) Cornute
stylophoran indet. (SNUP 2563) from the
Furongian of Korea. (k) Courtessolea
monceretorum (MNHN.F.A45783) from
the Cambrian Series 3 of France. All
photographs with the exception of (a) and
(g) were taken from latex casts whitened
with NH4Cl sublimate. For abbreviations:
see caption to Figure 13.3.
taxa (with a fully plated aboral surface and biserial flooring plates)
occur in West Gondwana (Fig. 13.3j). Stromatocystites has been
found in Australia, Bohemia, Morocco, Spain and Turkey (Pompeckj 1896; Jell et al. 1985; Smith & Jell 1990; Lefebvre et al.
2010), as well as in Baltica (Dzik & Orłowski 1995). The
closely related genus Cambraster has been reported from Australia, France and Spain (Jell et al. 1985; Smith 1985; Zamora et al.
2007b). Totiglobus is the Laurentian counterpart of Stromatocystites and Cambraster, but represents a distinct clade with very
reduced secondary cover plates, a more domed theca and no epispires (Bell & Sprinkle 1978; Sprinkle 1985). A third clade of
edrioasteroids, with quadriserial flooring plates, an uncalcified
aboral surface and pedunculate zone, is present in both North
America (Walcottidiscus) and China (Kailidiscus, Fig. 13.3k;
Smith 1985; Zhao et al. 2010). The oldest members of the Order
Isorophida (with uncalcified aboral surface and uniserial flooring plates) are known from West Gondwana, where they are represented by the genus Protorophus (Fig. 13.3f ) and an indeterminate
taxon, both from Cambrian Stage 5 of North Spain (Zamora &
Smith 2010). Finally, the fossil record of isolated plates assigned
to edrioasteroids (Kouchinsky et al. 2011, in press) suggests this
group was in Stages 3 (Kouchinsky et al. in press) and 5 (Kouchinsky et al. 2011) of Siberia, although no articulated specimens
have yet been described.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
162
S. ZAMORA ET AL.
The Furongian record of edrioasteroids is, by comparison,
extremely poor and includes only a handful of species. However, the little available evidence suggests that edrioasteroids
continued to diversify through the Furongian. Only four edrioasteroids have been recorded so far from the Furongian: one
indeterminate edrioasteroid from North America (Sumrall et al.
1997), a possible stromatocystitid from France (Ubaghs 1998)
and two isorophids from Australia, Chatsworthia and Hadrodiscus (Smith & Jell 1990), both of which have unplated
aboral surfaces. Finally, edrioblastoids (a derived clade of
edrioasteroids) first appeared in the Furongian (Fig. 13.3d); they
have been reported so far only from Australia (Cambroblastus
enubilatus; Smith & Jell 1990).
Eocrinoids
The ‘Class’ Eocrinoidea is a paraphyletic assemblage comprising stem-group members of most other blastozoan clades
(Ubaghs 1968a; Sprinkle 1973; Smith 1984; Paul 1988; Sumrall
1997; David et al. 2000). The body of eocrinoids generally consists of three parts (Fig. 13.3b): a sack-like theca that enclosed the
main viscera, the feeding appendages (brachioles) and an aboral
stalk or stem used for attachment and to elevate the theca above
the sea floor. In the most primitive taxa (e.g. Gogia and relatives),
this appendage consists of a long, multiplated stalk. In more
derived forms (e.g. Ubaghsicystis) it is a columnal-bearing stem.
This aboral appendage is absent in other taxa (e.g. Lichenoides).
Simple respiratory structures (epispires) occur frequently, more or
less extensively, over the theca of eocrinoids (Fig. 13.3b, c). The
presence of epispires is a plesiomorphic feature within echinoderms, which is lost in more advanced eocrinoids and other
blastozoans.
Eocrinoids commonly form the dominant echinoderm group
in Cambrian assemblages. The earliest eocrinoids include representatives of the ‘orders’, Imbricata and Gogiida. Imbricate eocrinoids are probably the most basal blastozoans (Sprinkle 1973; Paul
& Smith 1984). Their stalk is an unorganized, polyplated structure built of numerous imbricate elements (Fig. 13.3c). Cambrian
Series 3 imbricate eocrinoids are restricted to Laurentia (North
America) where there are just two genera, Lepidocystis and Kinzercystis (Sprinkle 1973). The oldest gogiid eocrinoid is Gogia
ojenai from the Stage 4 of Laurentia (Durham 1978). Early
gogiids from Gondwana are of approximately the same age as
their Laurentian counterparts. They are represented by Alanisicystis andalusiae and Alanisicystis sp. from the Marianian and
Banian stages of South Spain and Morocco, respectively
(Ubaghs & Vizcaı̈no 1990; Nardin & Lefebvre 2005), as well as
by Guizhoueocrinus yui (Fig. 13.3b) and Wudingeocrinus rarus
from Stage 4 of China (Zhao et al. 2007; Hu et al. 2007; Hu &
Luo 2008; Luo et al. 2008). Other West Gondwanan occurrences
of gogiids are based on isolated plates and their stratigraphical
range is comparable to that of articulated specimens. Isolated
gogiid plates have been recorded from the Comley of Britain
(Series 2; Donovan & Paul 1982), Germany (Elicki & Schneider
1992), from the slightly younger Bilbilian Stage of Jordan and
North Spain (Clausen 2004; Shinaq & Elicki 2007), and from
the Laurentian part of Newfoundland (Skovsted & Peel 2007).
Finally, other Cambrian Series 2 eocrinoid skeletal elements are
also known from Siberia (Rozanov & Zhuravlev 1992, p. 248;
Rozhnov et al. 1992; Kouchinsky et al. 2012, in press).
Eocrinoid faunas from Cambrian Series 3 strata show that basal
blastozoans had become more diversified. Imbricate eocrinoids
survived, but their only record is from the Přı́bram-Jince Basin
(Vyscystis ubaghsi; Fatka & Kordule 1990). This region has also
yielded a new, as yet unpublished, basal blastozoan, intermediate
in morphology between imbricates and gogiids (Nardin 2007). In
contrast, gogiids (Fig. 13.3e) are relatively common in siliciclastic
platforms of both Laurentia (Mexico and USA; Sprinkle 1973;
Sprinkle & Collins 2006; Nardin et al. 2009) and Gondwana
(China, Czech Republic, France and Spain; Fatka & Kordule
1984; Ubaghs 1987; Zhao et al. 2008; Zamora et al. 2009;
Parsley & Zhao 2010). Some morphological innovations in eocrinoids appeared apparently earlier in West Gondwana than in
Laurentia (Zamora 2010). For example, the possession of
columnal-bearing stems is documented both in Spain (Ubaghsicystis, Fig. 13.3g; Gil Cid & Domı́nguez 2002) and in the Přı́bramJince Basin (O. Fatka, pers. obs. 2010) as early as Cambrian
Stage 5, instead of the Guzhangian in Laurentia (e.g. Eustypocystis; see Sprinkle 1973). This earlier occurrence of holomeric stems
in articulated Gondwanan eocrinoids is also mirrored by the fossil
record of isolated columnals. Columnals are known from various
Gondwanan regions (Australia, Morocco, Sardinia and Turkey)
in levels very close to the boundary of Cambrian Series 2–3
(Elicki 2006; Clausen & Smith 2008; Clausen et al. 2009; Guensburg et al. 2010). They have been also reported from Baltica (BergMadsen 1986; Hinz-Schallreuter 2001). Lichenoidids are a group
of stemless eocrinoids that were apparently endemic to West
Gondwana (Fig. 13.3i). They are known from Bohemia (Ubaghs
1953) and Spain (Zamora 2010), and related plate taxa (Cymbionites and Peridionites) are known from Stage 5 in Australia
(Smith 1982; J. Sprinkle, pers. obs. 2013). Finally, long-stalked
eocrinoids appeared at the same time in both Laurentia and Gondwana. They include Balangicystis from China (Parsley & Zhao
2006; Sprinkle et al. 2011) and Lyracystis from North America
(Sprinkle & Collins 2006). Cambrian Series 3 eocrinoids are very
rare from Baltica, where only the enigmatic Cigara and isolated
thecal plates (assigned to Crucicystis) have been described
(Franzén-Bengston, in Berg-Madsen 1986; Hinz-Schallreuter 2001).
The Furongian marks a dramatic turnover in blastozoan assemblages, with the appearance of new clades able to colonize carbonate hardgrounds, which for the first time were becoming
widespread in warm to temperate shallow-water environments
(Brett et al. 1983). Unfortunately, the fossil record for this important time interval is extremely poor in most parts of the world
(Fig. 13.1). Apparently, eocrinoids with holomeric stems
(adapted to life on firm grounds and shell fragments), which first
appeared at the base of Cambrian Series 3 in West Gondwana,
expanded into these new niches (hardgrounds) during the Furongian (Zamora et al. 2010). Trachelocrinids are an example of
such rapidly diversifying eocrinoids adapted to life on hardgrounds
across the shallow carbonate platforms of Laurentia (Sprinkle
1973; Sumrall et al. 1997). In the Furongian of Siberia, Sumrall
et al. (2003) identified at least six different eocrinoid taxa (including both gogiids and columnal-bearing forms) based on poorly
articulated and disarticulated material.
Rhombifera
Rhombiferans are one of the dominant groups of Ordovician echinoderms (Lefebvre et al. 2013), but the roots of this clade can be
traced back into the Cambrian. Unlike their Ordovician relatives,
Cambrian rhombiferans lacked specialized respiratory structures
(rhombs), and their thecal plates were not standardized into
regular rows (Fig. 13.3h). Basal members include a new
group called dibrachicystids (Zamora & Smith 2012) bearing
two feeding appendages, thecal plates with respiratory folds and
a tripartite stem with distal holomeric columnals. Dibrachicystids
were originally described from isolated plates (Ubaghs 1967,
1987). These distinctive plates displaying a strong radial ornamentation are frequently reported under the name ‘Eocystites’. Articulated specimens of dibrachicystids have been found in Cambrian
Stage 5 rocks of both France and Spain (Zamora 2010; Zamora
& Smith 2012). Disarticulated dibrachicystid-like plates of the
same age have been reported from many other areas of West Gondwana, such as Germany, Morocco, Sardinia and Ossa –Morena
(southern Iberian Peninsula; Loi et al. 1995; Gil Cid & Domı́nguez
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
1998; Sdzuy 2000). Finally, Kouchinsky et al. (2011, fig. 38A –F)
described a series of isolated plates from the Drumian Stage of
Siberia that fit in size and morphology with the proximal stem
plates of dibrachicystids.
In the Furongian, more glyptocystitid-like rhombiferans
appeared both in Baltica (e.g. Cambrocrinus from Poland; Dzik
& Orłowski 1993) and Gondwana, such as Australia (Ridersia watsonae; Jell et al. 1985) and southern France (Velieuxicystis,
Fig. 13.3h, and Barroubiocystis; Ubaghs 1998). The widespread
distribution of glyptocystitid-like Gondwanan taxa in Furongian
times is confirmed by the presence of isolated plates in both Korea
and Wales (B. Lefebvre & S. Zamora, pers. obs. 2002, 2011).
Cincta
Cinctans are a small but distinctive clade of Cambrian Series 3
echinoderms. The cinctan skeleton consists of two parts: the
main body (or theca) and a posterior appendage (or stele;
Fig. 13.4d). The theca is constructed of a ring of large marginal
plates, the so-called cinctus. It is dorsally and ventrally covered
with two membranes of tessellate plates. The main body orifices
are situated in the anterior part of the theca, the mouth piercing
the cinctus and the anus piercing the supracentral integument.
One or usually two food grooves run laterally around the anterior
part of the cinctus. These grooves converge onto the mouth, which
is situated in the anterior right part of the cinctus. The stele is a posterior appendage, considered to be a prolongation of the cinctus
(Jefferies 1990; Friedrich 1993; Zamora & Smith 2008).
Cinctans apparently underwent rapid evolution within a short
time range (Cambrian Series 3; Smith & Zamora 2009), and
have a relatively restricted palaeobiogeographical distribution
(West Gondwana and Siberia). They have not been reported
from either Baltica or Laurentia. The oldest undisputed cinctan
remains correspond to isolated plates from the Leonian (Stage 5)
Mansilla Formation (Iberian Chains, Spain). The oldest named
species is Protocinctus mansillaensis (Rahman & Zamora 2009)
from the same formation, but slightly younger beds (upper
Leonian). The Czech species ‘Asturicystis’ havliceki is probably
also of similar age (late Leonian), although a precise stratigraphical correlation remains difficult to establish between Bohemia
and Spain (Fatka & Kordule 2001). Slightly younger are Asturicystis jaekeli and Sotocinctus ubaghsi from the Cambrian Stage 5 of
the Cantabrian Mountains (North Spain; Sdzuy 1993). Drumian
cinctan assemblages are more diverse and widespread in many
West Gondwanan areas (France, Germany, Morocco, Sardinia
and Wales), and are characterized by Elliptocinctus, Gyrocystis
(Fig. 13.4e), Lignanicystis (Fig. 13.4c), Progyrocystis, Sucocystis, Undatacinctus (Fig. 13.4f) and several species left in open
nomenclature (Cabibel et al. 1959; Schroeder 1973; Termier &
Termier 1973; Friedrich 1993, 1995; Gil Cid & Domı́nguez
Alonso 1995a, b; Loi et al. 1995; Zamora et al. 2007a; Zamora
& Smith 2008; Zamora & Rahman 2008; Smith & Zamora 2009;
Zamora & Álvaro 2010). The Drumian cinctans Trochocystites
bohemicus (Fig. 13.4d) and Trochocystoides parvus are endemic
from Bohemia. Another endemic genus was reported in the
Drumian of Wales, based on poorly preserved material (Friedrich
1993). The Siberian record of cinctans consists of two endemic
genera, Nelegerocystis and Rozanovicystis, both described from
the Drumian (Rozhnov 2006).
Cinctans become extinct close to the Drumian –Guzhangian
boundary. The youngest species include Undatacinctus melendezi,
U. aff. quadricornuta, and Sucocystis acrofera, all from France
and Spain (West Gondwana).
Ctenocystoidea
Ctenocystoids are possibly the most puzzling and enigmatic group
of Cambrian echinoderms. They have a nearly bilateral theca,
163
framed by one, or more frequently, two superposed rings of marginal plates (Fig. 13.4b), and lack a stem. As in cinctans, both
upper and lower thecal surfaces are covered by relatively flexible, tessellated membranes. The anterior part of the ctenocystoid
theca is formed by a ctenidium, a specialized organ covering the
mouth composed of a series of highly modified, tooth-like plates.
A single posterior aperture represents the anus (Robison & Sprinkle 1969; Domı́nguez Alonso 1999; David et al. 2000; Rahman &
Clausen 2009). Ctenocystoids were relatively short-ranged fossils, restricted to Cambrian Series 3 but achieving a remarkably
cosmopolitan palaeobiogeographical distribution. They may, however, have a longer range as one possible Late Ordovician ctenocystoids has been described (Domı́nguez Alonso 2004).
Ctenocystoids with a double-plated marginal ring have been
reported from western Laurentia (Ctenocystis utahensis,
Fig. 13.4b, and C. colodon; Robison & Sprinkle 1969; Ubaghs &
Robison 1988), and several Gondwanan regions, such as Australia
(Ctenocystis jagoi; Jell et al. 1985), Bohemia (Etoctenocystis
bohemica; Fatka & Kordule 1985), France (C. smithi; Ubaghs
1987) and Wales (Pembrocystis gallica; Domı́nguez Alonso
2004). Undescribed ctenocystoid species are known in both
Morocco (S. Clausen, pers. obs. 2011) and northern Spain (e.g.
Ctenocystis sp. and Etoctenocystis sp.; Zamora 2011). Ctenocystoids with a single-plated marginal ring are restricted to West
Gondwana. They were originally reported from Cambrian Stage
5 of southern France (Montagne Noire; Courtessolea monceretorum; Domı́nguez Alonso 2004; Fig. 13.4k). Courtessolea has
been found in Bohemia and Spain but awaits formal description
(Zamora 2010; O. Fatka, pers. obs. 2011). A distinctive form,
bearing highly reduced thecal plating, occurs in Poland (Jugoszowia; Dzik & Orłowski 1995). Isolated ctenocystoid plates have
been reported from Baltica (Sweden; Domı́nguez Alonso 2004).
Soluta
Solutans are a small, extinct clade of echinoderms that range from
the Cambrian to the Early Devonian. They have two unequal
appendages, inserted at opposite ends of the body (theca)
(Fig. 13.4a). The short, anterior appendage is made from biserial
(rarely uniserial) flooring plates and two opposite sets of cover
plates. It has been interpreted either as an arm (e.g. Smith 2005)
or a brachiole (e.g. David et al. 2000). The long posterior appendage is a stalk-like structure called a stele. In the most primitive
genus (Coleicarpus; Fig. 13.4a), the stele is a polyplated, unorganized holdfast. In all other taxa (including the contemporary Castericystis), this appendage is organized into a highly flexible,
proximal region and a rigid, distal portion whose plating differs
on upper and lower surfaces. The mouth was located at the base
of the feeding appendage. In most taxa, both the gonopore and
the hydropore are close to the insertion of the feeding appendage.
In all solutans, the anus forms a large thecal orifice, opening laterally, and close to the insertion of the stele.
The Cambrian record of solutans is extremely poor, and
restricted to Laurentia. Solutans did not appear in Gondwana
until the Early Ordovician, and in Baltica until the Mid Ordovician
(see Lefebvre et al. 2013). The earliest record of this class is a
questionable unnamed and unillustrated form from the Cambrian
Series 2 of Pennsylvania (Derstler 1975, 1981). Two genera
were described from Cambrian Series 3 deposits of Utah: Coleicarpus and Castericystis (Ubaghs & Robison 1985, 1988; Daley
1995, 1996). Coleicarpus is the most primitive solutan known
so far (Daley 1996; David et al. 2000). It attached to skeletal
debris on the sea floor and/or to any hard object by its stele. Castericystis is identical in age but has a more derived stele morphology, which was used for attachment only during juvenile
stages (Daley 1995). A third unnamed species based mostly on
separate steles was mentioned and illustrated from Cambrian
Series 3 deposits in Nevada (Sprinkle 1973, plate 28, fig. 4).
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
164
S. ZAMORA ET AL.
Their Furongian record is limited to two complete but unnamed
solutans that were briefly described from northern Alabama (Laurentia) and an unnamed species (Fig. 13.4g), also from Laurentia,
described from two isolated steles (Bell & Sprinkle 1980;
Sumrall et al. 1997).
Stylophora
Stylophorans are an extinct class of echinoderms (Cambrian Series
3–Late Carboniferous), characterized by a bipartite body organization (Fig. 13.4i), consisting of a single appendage and a flattened,
fundamentally asymmetrical theca. Their phylogenetic position
within the Phylum Echinodermata remains controversial. They
may represent primitive, relatively basal echinoderms (Ubaghs
1968b; Smith 2005) or a highly derived clade possibly related to
blastozoans (Sumrall 1997) or to arm-bearing echinoderms (e.g.
asterozoans and crinoids; David et al. 2000; Lefebvre 2003). The
class Stylophora is traditionally subdivided into two orders,
Cornuta (Jaekel 1901) and Mitrata (Jaekel 1918). The cornutes
(Cambrian Series 3–Late Ordovician) have a relatively rigid
appendage, and a generally light, delicate theca framed by
narrow marginal plates, whereas the mitrates (Furongian– Late
Carboniferous) have a comparatively more highly flexible distal
appendage and a more massive theca made from enlarged and
thickened marginals and centrals (Lefebvre 2001).
Stylophorans first appeared in Cambrian Series 3. The oldest
and most primitive members of the class are heavily plated
(‘armoured’) Ceratocystis-like taxa (Fig. 13.4i), which were
apparently adapted to relatively warm to temperate, shallow
waters (Lefebvre 2007). These basal stylophorans were restricted
to Baltica and West Gondwana. In Baltica, Ceratocystis-like
taxa are represented by isolated plates from Denmark (BergMadsen 1986) and several complete, fully articulated specimens
from Sweden (B. Lefebvre, pers. obs. 2009). Armoured stylophorans are much more abundant in West Gondwana, where they have
been reported from Bohemia (Pompeckj 1896; Jaekel 1901; Bather
1913; Ubaghs 1967; Jefferies 1969), southern France (Ubaghs
1987), Germany (Sdzuy 2000; Rahman et al. 2010), Morocco
(Clausen & Smith 2005), Sardinia (Loi et al. 1995), Spain (Gil
Cid & Domı́nguez Alonso 1998; Zamora 2010) and Wales (Jefferies et al. 1987). Like cinctans and several clades of trilobites,
the armoured stylophorans disappeared before the Furongian,
probably as a consequence of habitat loss related to a global
regression (Zamora & Álvaro 2010).
The first cothurnocystid cornutes appeared slightly later,
although still in Cambrian Series 3, and are found in what were
once soft substrates deposited in relatively deep, quiet
environments (Lefebvre 2007). Cothurnocystids were thus probably ‘psychrospheric’ (cold water-adapted) taxa, with a nearcosmopolitan distribution. They have been reported from
western Laurentia (e.g. Archaeocothurnus bifida, Ponticulocarpus
robisoni; Ubaghs & Robison 1988; Sumrall & Sprinkle 1999),
Siberia (Ponticulocarpus sp.; S. Rozhnov, pers. obs. 2002) and
Gondwana, such as Iran (Ponticulocarpus sp.; S. Rozhnov, pers.
obs. 2002) and Spain (Zamora 2010).
The Furongian record of stylophorans is relatively rich compared with that of most other echinoderm groups. Although still
insufficiently documented, this time interval marks a major turnover in stylophoran assemblages. Cothurnocystid cornutes are
the dominant and most diverse Furongian stylophorans (Fig.
13.4j). Their distribution is near-cosmopolitan, with occurrences
reported from Laurentia (e.g. Cardiocystella prolixora; Sumrall
et al. 1997, 2009) and various Gondwanan regions such as South
China (Han & Chen 2008), southern France (Ubaghs 1998) and
Korea (e.g. Sokkaejaecystis serrata; Lee et al. 2005). The Furongian interval also has recorded the first occurrences of several
new clades of stylophorans. For example, Drepanocarpos australis (Australia; Smith & Jell 1999) is the oldest and most primitive
known member of hanusiid cornutes (Lefebvre 2001, 2007).
Mitrates, long thought to originate in the Early Ordovician, are
now known to extend back at least to the Furongian. The heavily
plated stylophoran Lobocarpus vizcainoi (Fig. 13.4h) from
southern France (Ubaghs 1998) has been reinterpreted as a possible basal mitrate (Lefebvre 2000, 2001), while isolated plates of
peltocystids and several fully articulated specimens of primitive
mitrocystitids close to Chinianocarpos and/or Vizcainocarpus
are now known from Korea (Lefebvre 2007) and South China
(B. Lefebvre, pers. obs.).
The conspicuous record of disarticulated
echinoderm ossicles
Until recently, our understanding of echinoderm diversity and
evolution was based almost entirely on analysis of the distribution
of well-preserved, articulated specimens. These, however, come
predominantly from relatively deep-water palaeo-environments
below storm-wave base, where taphonomic conditions were
more favourable for such preservation. Because the distribution
of articulated specimens is possibly taphonomically biased, an
important and possibly more complete record of echinoderms is
provided by isolated plates, as these are much more commonly
encountered than articulated specimens in a much wider range of
palaeo-ecological settings (Fig. 13.5, see Supplementary material).
Fig. 13.5. Representative Cambrian
isolated plates (scanning electron
microscope photographs). (a, e). Uniserial
element from the Cambrian Series 2 of
Siberia (SMNH X 4047). (b, c) Stem
columnals from the Cambrian Series 3 of
Sardinia (FG 535/4_3, FG 535/4_5). (d)
Epispire bearing plate from the Cambrian
Series 3 of Jordan (FG 619/7_115). (f, g)
‘Eocystitid’ proximal stem plate from the
Cambrian Series 3 of Siberia (SMNH X
4016). (h) Ambulacral flooring plate from
the Cambrian Series 3 of Siberia (SMNH X
4046). Abbreviations: SMNH, Swedish
Museum of Natural History, Stockholm
(Sweden); FG, Geological Institute of the
Technische Universität Bergakademie
Freiberg (Germany).
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
Some Cambrian limestones are packed full of echinoderm elements, and those preserved as iron oxide, glauconite, phosphate
or silica replacements can be isolated and studied in 3D after
acid etching (e.g. Berg-Madsen 1986; Clausen & Smith 2005,
2008). Preliminary investigation of how isolated skeletal elements
from Cambrian limestones are distributed in space and time
suggests that they provide important additional information. The
study of isolated elements enhances our understanding of echinoderm palaeobiogeography in two major ways.
(1)
(2)
Echinoderm plates with their distinctive stereom structure
are easily identified from polished rock sections, and their
appearance in the rock record provides evidence of when
echinoderms first appeared across different palaeobiogeographical regions. Figure 13.6 summarizes the first occurrence
of echinoderm plates in the rock record in five major biogeographical regions. In two of the five regions, isolated echinoderm plates have been found in significantly to slightly older
deposits than those yielding articulated specimens. This
tabulation (Fig. 13.6) demonstrates that the echinoderms
first appeared approximately contemporaneously (slightly
above the Terreneuvian-Stage 3 boundary) in Laurentia,
Siberia and Gondwana, later in the geological record than
other phyla, such as arthropods, brachiopods or molluscs
(Landing et al. 2010).
While the majority of echinoderm plates are non-diagnostic
and offer little information other than simply the presence/
absence of echinoderms, some are distinctive and taxondiagnostic (i.e. ctenoidal plates from ctenocystoids, stylocones from stylophorans, marginal frame and opercular
plates of cinctans, marginal plates from some edrioasteroids,
holocolumnals from eocrinoids or the proximal stem plates
from ‘eocystitids’). These can provide important evidence
for the occurrence of certain taxa at times or in palaeogeographical regions where no articulated material is known
(Fig. 13.6). For example, diagnostic plates from eocrinoids
provide the only records we have that members of this
group existed in Baltica and Australia during the Cambrian.
In Australia, distinctive silicified holocolumnals can be
extracted after etching of bioclastic limestones long before
the earliest record of articulated blastozoans with holomeric
165
stems. Isolated stylocones in Morocco provide the earliest
record of ceratocystid stylophorans in West Gondwana
(Clausen & Smith 2005). Finally, numerous localities are
known where isolated cinctan marginal plates are abundant
yet from where named species have yet to be recorded. Isolated elements can also reveal unexpected diversity, as in
the case of the variety of distinct holocolumnal morphotypes
found by Clausen & Smith (2008) in Cambrian Stage 5 condensed levels of Morocco. The recognition that many groups
appeared earlier in shallow carbonate platforms than in offshore clayey substrates indicates that an important part of
the early record of echinoderm evolution from relatively
shallow settings is missing.
Palaeobiogeographical patterns
First appearances in Laurentia and Gondwana
Figure 13.6 charts the first occurrence data for our eight echinoderm clades in space and time. Evidence for echinoderms first
appears at same time in different palaeocontinents (early Series
2). However, there is a strong endemic constraint in the earliest
records, with the first identifiable echinoderms from Laurentia
being helicoplacoids and edrioasteroids. Eocrinoids (Imbricata
and Gogiida) appeared one stage later. In contrast, the earliest
representatives from Gondwana of similar age (Cambrian Stage
3) are gogiid eocrinoids (Alanisicystis from Ossa– Morena and
Morocco). Edrioasteroids are present but do not appear in the
Gondwanan record until slightly later (?Stromatocystites sp.
from Northern Spain and Edriodiscus and Stromatocystites from
Australia). Despite these differences, gogiid eocrinoids and
edrioasteroids are consistently the first to appear in the fossil
record across all regions (Fig. 13.6).
Cinctans, ctenocystoids, solutans, stylophorans and most other
groups of radiate echinoderms all appear in Cambrian Stage 5.
The clear distinction that exists between these groups right from
the very start of their records, and their near synchronicity of appearance, strongly suggests that we are missing the earliest part of
their history and that all these groups most likely diverged during
Fig. 13.6. Table charting the first
occurrences of eight major groups of
echinoderm in each of five biogeographical
regions. The first record of stereom in plates
and of holomeric columnals in the rock
record is marked.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
166
S. ZAMORA ET AL.
Table 13.1. Distribution of 21 Cambrian echinoderm groups in seven palaeogeographical regions
Major clades
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Laurentia
Baltica
West Gondwana
Arabian margin
Siberia
East Gondwana (Australia)
East Gondwana (China and Korea)
1
0
0
0
0
0
0
0
0
1
0
1
0
0
1
0
0
0
0
0
0
1
1
1
0
0
1
0
0
1
1
0
0
0
0
1
0
1
1
1
1
1
0
0
1
0
0
0
1
0
0
1
0
1
1
1
0
0
1
0
0
0
0
0
1
1
1
0
1
0
1
0
0
0
0
0
0
0
0
1
1
0
1
0
1
0
1
0
0
0
0
1
0
1
0
0
0
1
1
0
0
0
0
0
0
1
0
0
0
0
0
1
1
0
1
0
1
0
0
0
0
1
0
0
1
0
0
0
0
0
0
1
0
1
0
0
0
0
0
1
0
0
1
0
0
0
0
Taxa numbered as follows: 1, helicoplacoids; 2, cinctans; 3, solutans; 4, ctenocystoids; 5, ceratocystitid stylophorans; 6, cothurnocystid stylophorans; 7, mitrate
stylophorans; 8, primitive glyptocystitid rhombiferans; 9, eocystitid rhombiferans; 10, stromatocystitid edrioasteroids; 11, edrioasterid-like edrioasteroids; 12, isorophid
edrioasteroids; 13, imbricate eocrinoids; 14, gogiid eocrinoids; 15; trachelocrinid eocrinoids; 16, lyracystid eocrinoids; 17, column-bearing eocrinoids; 18, cambrasterid
edrioasteroids; 19, edrioblastoid edrioasteroids; 20, kailidiscid edrioasteroids; 21, lichenoidid eocrinoids.
Cambrian Series 2 or earlier. Consequently, the order in which
groups appear in the fossil record must be treated with caution.
Biogeographical relationships of echinoderm assemblages
The closeness of relationships shown by the Cambrian echinoderms can be assessed by analysing the biogeographical distribution of individual clades. Although there is no agreed global
phylogeny for all echinoderms, many of the constituent groups
are widely recognized and accepted as potentially monophyletic.
For example, there has never been any disagreement that cinctans
and ctenocystoids form well-defined clades. Each of these clades
inhabited one or more biogeographical regions; by analysing the
pattern of shared occurrences, the degree of similarity of those
regions can be established using Parsimony Analysis of Endemism
(Rosen & Smith 1988; Da Silva & Oren 2008).
Here we map the distribution of 21 Cambrian clades
(Table 13.1) across seven palaeogeographical regions [Laurentia
(USA and western Canada), West Gondwana (Morocco, southern
Europe and Bohemia), Far East Gondwana (China and Korea),
Australia, Arabian margin (Turkey and Iran), Baltica and
Siberia]. The distribution of each clade is summarized in
Table 13.1. Figure 13.7 shows the results of a Parsimony Analysis
of Endemism carried out under Dollo Parsimony (which prohibits
the same taxon from arising more than once independently in
different geographical areas). Only four of these regions (Laurentia, West Gondwana, East Gondwana and Australia) are sufficiently densely sampled to provide reliable patterns; in other,
poorly sampled, regions our inability to distinguish between
genuine absences from the region and absences from inadequate
sampling makes interpretation problematic.
Turning first to the four regions for which we have a moderately
good sample, our analysis clearly distinguishes between a pairing
of Laurentia and East Gondwana and a pairing of Australia and
West Gondwana. Laurentia and East Gondwana both uniquely
have lyracystids and kailidiscid edrioasteroids as part of their
fauna, while Australia and West Gondwana share isorophids,
stromatocystitids and cambrasterids. Baltica has representatives
of just three echinoderm clades, one of which is shared with Australia and West Gondwana, and another (glyptocystitid-like rhombiferans) shared uniquely with West Gondwana. The Arabian
margin of Gondwana has just two clades, the near-cosmopolitan
cothurnocystid stylophorans and one shared with Baltica, Australia and West Gondwana (stromatocystitids). The pairing of the
Arabian margin with Baltica is probably a bias of poor sampling
as they are united only by implied secondary losses of lineages.
Finally, Siberia has representatives of four clades and provides
a mixed signal. Stylophorans are present in Siberia, but these
display a near-cosmopolitan distribution. Column-bearing eocrinoids are also present, but these are shared with both Laurentia
and West Gondwana and are therefore uninformative. The same
is true for early glyptocystitids, a taxon that Siberia shares
with West and East Gondwana, as well as with Australia. However, Siberia uniquely shares with West Gondwana the presence
of cinctans, suggesting that the Siberian echinoderm fauna may
be closer to that of West Gondwana and Australia than to that of
Laurentia and East Gondwana.
Laurentia has the longest branch of any region, possibly reflecting the better sampling available there. Four of the six endemic
clades in our analysis come from Laurentia.
Alpha diversity in space and time
The Cambrian fluctuations of echinoderm diversity is partly
driven by the distribution of appropriate facies where echinoderms
have been preserved as articulated specimens (Smith 1988;
Zamora & Álvaro 2010) and in part by important ecological changes (i.e. the so-called Cambrian Substrate Revolution;
Dornbos 2006; Zamora et al. 2010). This means that a direct
reading of the fossil record may inform us just as much about
sampling in space and time as it does about echinoderm evolution. A simple plot of the raw data (Fig. 13.1d, e) might be
taken to imply that Cambrian Series 3 was a time of palaeobiogeographical expansion for many echinoderm classes, while the
Fig. 13.7. Biogeographical relationships of seven regional Cambrian faunas
based on a Parsimony Analysis of Endemism of 21 echinoderm clades
(Table 13.1) under Dollo Parsimony. Important shared clades are indicated on the
diagram that link two or more regions. Note that very low numbers of taxa
recorded from Baltica and the Arabian margin mean that these regions are united
only by shared secondary losses, absences that probably reflect undersampling of
these regions rather than biogeographical signature. Boxes indicate important
echinoderm taxa that characterize different regions of the tree.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
167
(a)
(b)
(c)
Fig. 13.8. Echinoderm alpha diversity
through the Cambrian based on articulated
specimens. (a) Table of mean alpha
diversity (average number of species per
formation per stage) for six major
biogeographical regions (as in Fig. 13.1
colours indicate relative level of alpha
diversity). (b) Mean global alpha diversity
in the 10 Cambrian stages. (c) Comparison
of mean alpha diversity per stage in West
Gondwana and Laurentia.
Furongian recorded a marked decline. Assemblages in Cambrian
Series 3 were dominated by cinctans in many West Gondwanan
areas and by gogiid eocrinoids in East Gondwana (China) and
Laurentia. Gondwanan assemblages from offshore and relatively
shallow-water environments are apparently more diverse than
those from deeper-water settings of East Gondwana and Laurentia.
There are other groups that dominate benthic assemblages in
some specific levels but are very rare in others. This is the case
for edrioasteroids (e.g. Stromatocystites), ctenocystoids (e.g. Ctenocystis utahensis) or stylophorans (e.g. Ceratocystis perneri).
Furongian communities are dominated by eocrinoids and
stylophorans, with fewer solutans and edrioasteroids, in Laurentia
(Sumrall et al. 1997). Development of the first carbonate hardgrounds in Laurentia may have allowed the immigration of
Gondwanan faunas that were pre-adapted to such substrates in
Cambrian Series 3 firmgrounds (Zamora et al. 2010). In France,
rhombiferans and stylophorans were the dominant groups in
mixed (carbonate– siliciclastic) environments.
However, we know that sampling is possibly much better in
Cambrian Series 3 than in lower Furongian strata. To reduce the
bias introduced by uneven sampling, we use counts of the
number of species recorded from single formations. This measures
alpha diversity (i.e. within formation species richness), and allows
us to compare diversity patterns across regions that have very
different numbers of echinoderm-bearing formations. The results
are shown in Figure 13.8 and there are several notable features
to emerge from this:
(1)
Cambrian Series 2 formations typically yield two species,
each from its own monotypic level. The Poleta Formation
(Cambrian Stage 4) of Laurentia appears to be an anomaly,
as it has yielded four species (three helicoplacoids and one
edrioasteroid). However, in this case one helicoplacoid and
the edrioasteroid (which is known from numerous isolated
plates) completely dominate the assemblage and the other
two are known only from single specimens. Formations
that contain a significant alpha diversity first appeared in
Cambrian Stage 5 of West Gondwana where, for the first
time, we begin to find as many as eight species represented
by numerous specimens and preserved in a single bed (e.g.
the Purujosa section; Zamora 2010). This implies that there
was a genuine increase in echinoderm diversity going into
Cambrian Series 3. Part of the reason why there are so
(2)
(3)
many formations yielding echinoderms in Series 3 is
because echinoderms themselves were becoming more abundant and widespread.
Lower Furongian formations show diversity levels that are as
low as those of the Stage 3, suggesting that there is a genuine
drop in diversity at this time. This pattern is repeated in Laurentia, West Gondwana and China. However, we cannot
discount the possibility that this drop is because we are
sampling a smaller range of palaeo-environments than for
other time spans. There is no doubt that in many regions
this is an interval characterized by regional regressions
which induced the onset of stratigraphical gaps and a
record of coarse-grained substrates that precluded the preservation of fossiliferous strata.
Later Furongian formations on average have the highest
levels of alpha diversity (Fig. 13.8c) of any Cambrian stage
in Laurentia, but in West Gondwana and China alpha diversity only returns to match levels achieved in Cambrian
Series 2.
Conclusions
The compilation of a complete inventory of fossil echinoderm
occurrences throughout the Cambrian comprises records of both
articulated specimens and isolated echinoderm plates. Analysis
of these data shows that:
(1)
(2)
(3)
(4)
The Cambrian record of echinoderms spans something like
30 million years. During this time faunas changed
compositionally.
The distribution of formations yielding fossil echinoderms is
not evenly spread through space and time. Siberia, the
Arabian margin of Gondwana, South America and Baltica
are particularly under-represented and only Laurentia provides an unbroken record throughout the Cambrian.
The record of isolated echinoderm plates, although often
overlooked, yields important data on echinoderm distribution
in space and time. Specifically, it provides the only evidence
of eocrinoids from Australia and Baltica.
The earliest echinoderms, known from isolated stereombearing plates, appear contemporaneously in Laurentia,
Siberia and Gondwana.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
168
(5)
(6)
(7)
S. ZAMORA ET AL.
Evidence for a number of groups is first provided by isolated elements, and only later by articulated fossils.
Onshore environments, such as shallow-water carbonate
platforms, have a comparatively poor record of articulated
specimens, and thus our view of echinoderm evolution at
this time is biased.
Raw diversity over time points to a major increase in diversity, concentrated in West Gondwana, during Cambrian
Stage 5 and to very low diversity levels during the Guzhangian and Paibian. However, analysis of alpha diversity
shows that much of this variation may reflect sampling
biases, although there is a genuine rise in diversity through
the Cambrian in both Laurentia and Gondwana.
Parsimony Analysis of Endemicity indicates a close relationship between the echinoderm faunas of Australia and West
Gondwana and between those of East Gondwana (China
and Korea) and Laurentia. Low sampling in other regions
makes interpretation problematic.
This work is a contribution to the Projects Consolı́der MURERO number
CGL2006-12975/BTE from MEC and to the project CGL 2010-19491 from
MICINN-FEDER, INSU (SYSTER) project AO2012-786879 ‘contextes temporal, environnemental et écologique de l’initiation de l’intervalle glaciaire au
Paléozoı̈que inférieur’, and to the team ‘Couplages Lithosphére-Océan-Atmosphére’ (UMR CNRS-UPS-IRD 5563). This paper is also a contribution of the
team ‘Vie Primitive, biosignatures, milieux extrêmes’ of UMR CNRS 5276,
and to the ANR project RALI ‘Rise of Animal Life (Cambrian– Ordovician) –
organization and tempo: evidence from exceptionally preserved biota’. We
thank I. Pérez (MEC-FSE) for preparing the plates and some photographs of
this paper and A. Rushton (London) for his information about the Cambrian of
Wales. A. Kouchinsky acknowledges support from the NordCEE project grant
DNRF53 to D. Canfield from Danish National Research Foundation (Danmarks
Grundforskningsfond). Two reviewers, T. Guensburg (USA) and M. Reich
(Germany), provided important comments that greatly improved the resulting
manuscript.
References
´ lvaro, J. J., Ahlberg, P. et al. 2013. Global Cambrian trilobite
A
palaeobiogeography assessed using parsimony analysis of endemicity. In: Harper, D. A. T. & Servais, T. (eds) Early Palaeozoic
Biogeography and Palaeogeography. Geological Society, London,
Memoirs, 38, 273– 296, http://dx.doi.org/10.1144/M38.19
Ausich, W. I. & Babcock, L. E. 1998. The phylogenetic position of Echmatocrinus brachiatus, a probable octocoral from the Burgess Shale.
Palaeontology, 41, 193 –202.
Bather, F. A. 1913. Caradocian Cystidea from Girvan. Royal Society of
Edinburgh, Transactions, 49, 359 – 529.
Bell, W. C. 1948. Acetic acid etching technique applied to Cambrian brachiopods. Journal of Paleontology, 22, 101– 102.
Bell, B. M. & Sprinkle, J. 1978. Totiglobus, an unusual new edrioasteroid from the Middle Cambrian of Nevada. Journal of Paleontology,
52, 243 – 266.
Bell, G. L., Jr. & Sprinkle, J. 1980. New homiostelean echinoderms
from the Late Cambrian of Alabama. Geological Society of
America Abstracts with Programs, 12, 385.
Berg-Madsen, V. 1986. Middle Cambrian cystoid (sensu lato) stem
columnals from Bornholm, Denmark. Lethaia, 19, 67 –80.
Brett, C. E., Liddell, W. D. & Derstler, K. L. 1983. Late Cambrian
hard substrate communities from Montana/Wyoming: the oldest
known hardground encrusters. Lethaia, 16, 281 – 289.
Cabibel, J., Termier, H. & Termier, G. 1959. Les échinodermes mésocambriens de la Montagne Noire (Sud de la France). Annales de
Paléontologie, 44, 281 – 294.
Caron, J.-B., Conway Morris, S. & Shu, D. 2010. Tentaculate fossils
from the Cambrian of Canada (British Columbia) and China
(Yunnan) interpreted as primitive deuterostomes. PloS One, 5, 1– 13.
Clausen, S. 2004. New Early Cambrian eocrinoids from the Iberian
Chains (NE Spain) and their role in nonreefal benthic communities.
Eclogae Geologicae Helvetiae, 97, 371 –379.
Clausen, S. & Smith, A. B. 2005. Palaeoanatomy and biological affinities of a Cambrian problematic deuterostome (Stylophora).
Nature, 438, 351 – 354.
Clausen, S. & Smith, A. B. 2008. Stem structure and evolution in the
earliest pelmatozoan echinoderms. Journal of Paleontology, 82,
737 – 748.
Clausen, S., Jell, P. A., Legrain, X. & Smith, A. B. 2009. Pelmatozoan
arms from the Middle Cambrian of Australia: bridging the gap
between brachioles and brachials? Lethaia, 42, 283 –296.
Clausen, S., Hou, X. G., Bergström, J. & Franzén, C. 2010. The absence
of echinoderms from the Lower Cambrian Chengjiang fauna of China:
palaeoecological and palaeogeographical implications. Palaeogeography, Palaeoclimatology, Palaeoecology, 294, 133–141.
Daley, P. E. J. 1995. Anatomy, locomotion and ontogeny of the solute
Castericystis vali from the Middle Cambrian of Utah. Geobios, 28,
585 – 615.
Daley, P. E. J. 1996. The first solute, which is attached as an adult: a MidCambrian fossil from Utah with echinoderm and chordate affinities.
Zoological Journal of the Linnean Society, 117, 405 – 440.
Da Silva, J. M. C. & Oren, D. C. 2008. Application of parsimony analysis
of endemicity in Amazonian biogeography: an example with primates. Biological Journal of the Linnean Society, 59, 427 – 437.
David, B., Lefebvre, B., Mooi, R. & Parsley, R. 2000. Are homalozoans
echinoderms? An answer from the extraxial-axial theory. Paleobiology, 26, 529– 555.
Derstler, K. L. 1975. Carpoid echinoderms from Pennsylvania. Geological Society of America Abstracts with Programs, 7, 48.
Derstler, K. L. 1981. Morphological diversity of Early Cambrian
echinoderms. In: Taylor, M. E. (ed.) Short Papers for the Second
International Symposium on the Cambrian System. US Geological
Survey, Reston, VA, Open File Report, 81-743, 71– 75.
Domı́nguez Alonso, P. 1999. The early evolution of echinoderms:
The class Ctenocystoidea and its closest relatives revisited. In:
Candia Carnevali, M. D. & Bonasoro, F. (eds) Echinoderm
Research 1998: Proceedings of the Fifth European Conference on
Echinoderms, Milan, Italy, 7 – 12 September 1998. A. A. Balkema,
Rotterdam, 263 –268.
Domı́nguez Alonso, P. 2004. Sistemática, anatomı́a, estructura y
función de Ctenocystoidea (Echinodermata Carpoidea del Paleozoico inferior). PhD, Universidad Complutense, Madrid, http://
eprints.ucm.es/tesis/bio/ucm-t23248.pdf
Donovan, S. K. & Paul, C. R. C. 1982. Lower Cambrian echinoderm
plates from Comley, Shropshire, England. Geological Magazine,
119, 611– 614.
Dornbos, S. Q. 2006. Evolutionary palaeoecology of early epifaunal
echinoderms: response to increasing bioturbation levels during the
Cambrian radiation. Palaeogeography, Palaeoclimatology, Palaeoecology, 237, 225 – 239.
Durham, J. W. 1967. Notes on the Helicoplacoidea and early echinoderms. Journal of Paleontology, 41, 97– 102.
Durham, J. W. 1974. Systematic position of Eldonia ludwigi Walcott.
Journal of Paleontology, 48, 750 – 755.
Durham, J. W. 1978. A Lower Cambrian eocrinoid. Journal of Paleontology, 52, 195– 199.
Durham, J. W. 1993. Observations on the Early Cambrian helicoplacoid
echinoderms. Journal of Paleontology, 67, 590– 604.
Durham, J. W. & Caster, K. E. 1963. Helicoplacoidea: a new class of
echinoderms. Science, 140, 820– 822.
Dzik, J. & Orłowski, S. 1993. The Late Cambrian eocrinoid Cambrocrinus. Acta Palaeontologica Polonica, 38, 21 –34.
Dzik, J. & Orłowski, S. 1995. Primitive ctenocystoid echinoderm from
the earliest Middle Cambrian of Poland. Annales de Paléontologie,
81, 17 – 35.
Elicki, O. 2006. Microbiofacies analysis of Cambrian offshore carbonates from Sardinia (Italy): environment reconstruction and development of a drowning carbonate platform. Carnets de Géologie,
1, 1 –22.
Elicki, O. & Schneider, J. 1992. Lower Cambrian (Atdabanian/Botomian) shallow-marine carbonates of the Görlitz Synclinorium
(Saxony/Germany). Facies, 26, 55– 66.
Fatka, O. & Kordule, V. 1984. Acanthocystites Barrande, 1887 (Eocrinoidea) from the Jince Formation (Middle Cambrian) of the
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
Barrandian area. Vestnı́k Ústrednı́ho ústavu geologického (Bulletin of
Geosciences), 59, 299 – 302.
Fatka, O. & Kordule, V. 1985. Etoctenocystis bohemica gen. et sp. nov.,
new ctenocystoid from Czechoslovakia (Echinodermata, Middle
Cambrian). Vestnı́k Ústrednı́ho ústavu geologického (Bulletin of
Geosciences), 60, 225 – 230.
Fatka, O. & Kordule, V. 1990. Vyscystis ubaghsi gen. et sp. nov., imbricate eocrinoid from Czechoslovakia (Echinodermata, Middle Cambrian). Věstnı́k Ústřednı́ho ústavu geologického (Bulletin of
Geosciences), 65, 315 – 323.
Fatka, O. & Kordule, V. 2001. Asturicystis havliceki sp. nov. (Echinodermata, Homostelea) from the Middle Cambrian of Bohemia
(Barrandian area, Czech Republic). Časopis České Geologické
Společnosti (Journal of the Czech Geological Society), 46, 189 – 193.
Friedrich, W. P. 1993. Systematik und Funktionsmorphologie mittelkambrischer Cincta (Carpoidea, Echinodermata). Beringeria, 7,
1 – 190.
Friedrich, W. P. 1995. Neue Nachweise mittelkambrischer Cincta (Carpoidea, Echinodermata) aus Marokko, Sardinien und Süd-Wales.
Beringeria, Special Issue, 2, 255 –269.
Gehling, J. G. 1987. Earliest known echinoderm – a new Ediacaran fossil
from the Pound Subgroup of South Australia. Alcheringa, 11,
337 – 345.
Gil Cid, M. D. & Domı́nguez Alonso, P. 1995a. Gyrocystis cruzae, una
nueva especie de Cincta (Echinodermata Carpoidea) del Cámbrico
Medio del Ferredal de Quintana (Asturias, España). Boletı́n Geológico y Minero, 106, 517 – 531.
Gil Cid, M. D. & Domı́nguez Alonso, P. 1995b. Presencia de Gyrocystis
Jaekel, 1918 en el Cámbrico Medio de Zafra (Badajoz). Revista de la
Sociedad Geológica de España, 8, 99 –110.
Gil Cid, M. D. & Domı́nguez Alonso, P. 1998. ‘Carpoidea’ and Pelmatozoa from the Middle Cambrian of Zafra (SW Spain). In: Mooi, R. &
Telford, M. (eds) Echinoderms: San Francisco. A. A. Balkema,
Rotterdam, 93 –98.
Gil Cid, M. D. & Domı́nguez Alonso, P. 2002. Ubaghsicystis
segurae nov. gen. y sp., nuevo Eocrinoide (Echinodermata) del
Cámbrico Medio del Norte de España. Coloquios de Paleontologı́a,
53, 21 – 32.
Guensburg, T. E., Mooi, R., Sprinkle, J., David, B. & Lefebvre, B.
2010. Pelmatozoan arms from the mid-Cambrian of Australia: bridging the gap between brachioles and brachials? Comment: there
is no bridge. Lethaia, 43, 432– 440. http://dx.doi.org/10.1111/j.
1502-3931.2010.00220.x.
Han, N. R. & Chen, G. Y. 2008. New stylophorans (Echinodermata) from
the Upper Cambrian of Guangxi, South China. Science in China,
Series D: Earth Sciences, 51, 181 –186.
Hinz-Schallreuter, I. 2001. Crucicystis cruciformis gen. et. sp. nov.,
ein neuer Eocrinoide aus dem Mittelkambrium von Bornholm.
Greifswalder Geowissenschaftliche Beiträge, 9, 55– 61.
Hu, S.-X. & Luo, H.-L. 2008. Echinodermata. In: Luo, H.-L., Li, Y.
et al. (eds) Early Cambrian Malong Fauna and Guanshan Fauna,
from Eastern Yunnan, China. Yunnan Science and Technology
Press, Kunming, 102 –104, 133.
Hu, S. X., Luo, H. L., Hou, S. G. & Erdtmann, B. D. 2007.
Eocrinoid echinoderms from the Lower Cambrian Guanshan
Fauna in Wuding, Yunnan, China. Chinese Science Bulletin, 52,
717 – 719.
Jaekel, O. 1901. Über Carpoideen: eine neue Klasse von Pelmatozoen.
Zeitschrift der Deutschen Geologischen Gesellschaft, 52, 661 –677.
Jaekel, O. 1918. Phylogenie und System der Pelmatozoen. Paläontologische Zeitschrift, 3, 1– 128.
Jefferies, R. P. S. 1969. Ceratocystis perneri – a Middle Cambrian chordate with echinoderm affinities. Palaeontology, 12, 494– 535.
Jefferies, R. P. S. 1990. The solute Dendrocystoides scoticus from the
upper Ordovician of Scotland and the ancestry of chordates and echinoderms. Palaeontology, 33, 631 –679.
Jefferies, R. P. S., Lewis, M. & Donovan, S. K. 1987. Protocystites
menevensis – a stem-group chordate (Cornuta) from the Middle
Cambrian of South Wales. Palaeontology, 30, 429 –484.
Jell, P. A., Burrett, C. F. & Banks, M. R. 1985. Cambrian and
Ordovician echinoderms from eastern Australia. Alcheringa, 9,
183 – 208.
169
Kouchinsky, A., Bengtson, S., Clausen, S., Gubanov, A., Malinky,
J. M. & Peel, J. S. 2011. A middle Cambrian fauna of skeletal fossils
from the Kuonamka Formation, northern Siberia. Alcheringa, 35,
123– 189.
Kouchinsky, A., Bengtson, S., Runnegar, B., Skovsted, C., Steiner,
M. & Vendrasco, M. J. 2012. Chronology of early Cambrian biomineralisation. Geological Magazine, 149, 221 –251.
Kouchinsky, A., Bengtson, S., Clausen, S. & Vendrasco, M. J. in
press. A lower Cambrian fauna of skeletal fossils from the Emyaksin
Formation, northern Siberia. Acta Palaeontologica Polonica, http://
dx.doi.org/10.4202/app.2012.0004
Landing, E., Peng, S., Babcock, L. E. & Moczydłowska-Vidal, M.
2007. Global standard names for the lowermost Cambrian series
and stages. Episodes, 30, 283 –291.
Landing, E., English, A. & Keppie, J. D. 2010. Cambrian origin of all
skeletalized metazoan phyla – discovery of Earth’s oldest bryozoans
(Upper Cambrian, southern Mexico). Geology, 38, 547 – 550.
Lee, S., Lefebvre, B. & Choi, D. K. 2005. Latest Cambrian cornutes
(Echinodermata: Stylophora) from the Taebaeksan Basin, Korea.
Journal of Paleontology, 79, 139– 151.
Lefebvre, B. 2000. A new mitrate (Echinodermata, Stylophora) from the
Tremadoc of Shropshire (England) and the origin of the Mitrocystitida. Journal of Paleontology, 74, 890 – 906.
Lefebvre, B. 2001. A critical comment on ‘ankyroids’ (Echinodermata,
Stylophora). Geobios, 34, 597 –627.
Lefebvre, B. 2003. Functional morphology of stylophoran echinoderms.
Palaeontology, 46, 511 – 555.
Lefebvre, B. 2007. Early Palaeozoic palaeobiogeography and palaeoecology of stylophoran echinoderms. Palaeogeography, Palaeoclimatology, Palaeoecology, 245, 156 – 199.
Lefebvre, B., Hosgör, I., Nardin, E., Fatka, O. & Goncuoglu, C.
2010. First report of Stromatocystites (Echinodermata) from the
Middle Cambrian of Turkey: Palaeobiogeographic implications.
Geologica Balcanica, 39, 227 – 228.
Lefebvre, B., Sumrall, C. D. et al. 2013. Palaeobiogeography of
Ordovician echinoderms. In: Harper, D. A. T. & Servais, T. (eds)
Early Palaeozoic Palaeobiogeography and Palaeogeography. Geological Society, London, Memoirs, 38, 173–198, http://dx.doi.org/10.
1144/M38.14
Loi, A., Pillola, L. & Leone, F. 1995. The Cambrian and Early Ordovician of south-western Sardinia. Rediconti del Seminario della Facoltà
di Scienze dell’Univeristà di Cagliari, 65 (suppl.), 63 –71.
Luo, H., Li, Y. et al. 2008. Early Cambrian Malong Fauna and Guanshan Fauna from Eastern China. Yunnan Science and Technology
Press, Kunming.
Mankiewicz, C. 1992. Obruchevella and other microfossils in the
Burgess Shale: preservation and affinity. Journal of Paleontology,
66, 717– 729.
Nardin, E. 2007. La diversification des blastozoaires (Echinodermata) au
Paléozoı̈que inférieur: aspects phylogénétiques, paléoécologiques et
paléobiogéographiques. Unpublished PhD thesis, Université de
Bourgogne, Dijon.
Nardin, E. & Lefebvre, B. 2005. Earliest eocrinoids in the western AntiAtlas (Morocco): implications about their palaeogeography and their
relationships. In: Abstract Book, Climatic and Evolutionary Controls
on Palaeozoic Reefs and Bioaccumulations, 7– 9 September 2005.
MNHN, Paris, 45– 46.
Nardin, E., Almazán-Vázquez, E. & Buitrón-Sánchez, B. E. 2009.
First report of Gogia (Eocrinoidea, Echinodermata) from the
Early–Middle Cambrian of Sonora (Mexico), with biostratigraphical
and palaeoecological comments. Geobios, 42, 233 – 242.
Parsley, R. L. & Zhao, Y. 2006. Long-stalked eocrinoids in the basal
Middle Cambrian Kaili Biota, Taijiang County, Guizhou Province,
China. Journal of Paleontology, 80, 1058–1071.
Parsley, R. L. & Zhao, Y. 2010. A new turban-shaped gogiid eocrinoid
from the Kaili Formation, (Kaili Biota), Balang, Jianhe County,
Guizhou Province, China. Journal of Paleontology, 84, 549 – 553.
Paul, C. R. C. 1988. The phylogeny of the cystoids. In: Paul, C. R. C. &
Smith, A. B. (eds) Echinoderm Phylogeny and Evolutionary Biology.
Clarendon Press, Oxford, 199 – 213.
Paul, C. R. C. & Smith, A. B. 1984. The early radiation and phylogeny of
echinoderms. Biological Reviews, 59, 443– 481.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
170
S. ZAMORA ET AL.
Peng, S. C. & Babcock, L. E. 2008. Cambrian Period. In: Ogg, J. G., Ogg,
G. & Gradstein, F. M. (eds) A Concise Geologic Time Scale. Cambridge University Press, Cambridge, 37 –46.
Peng, S. C., Babcock, L. E., Robison, R. A., Lin, H. L., Rees, M. N. &
Saltzman, M. R. 2004. Global standard stratotype-section and point
(GSSP) of the Furongian Series and Paibian Stage (Cambrian).
Lethaia, 37, 365 – 379.
Pompeckj, J. F. 1896. Die Fauna des Cambrium von Tejrovic und Skrej in
Böhmen. Jahrbuch der kaiserlich-königlichen geologischen Reichsanstalt, 45, 495 – 614.
Rahman, I. A. & Clausen, S. 2009. Re-evaluating the palaeobiology and
affinities of the Ctenocystoidea (Echinodermata). Journal of Systematic Palaeontology, 7, 413 –426.
Rahman, I. A. & Zamora, S. 2009. The oldest cinctan carpoid (stemgroup Echinodermata) and the evolution of the water vascular system.
Zoological Journal of the Linnean Society, 157, 420 – 432.
Rahman, I. A., Zamora, S. & Geyer, G. 2010. The oldest stylophoran
echinoderm: a new Ceratocystis from the Middle Cambrian of
Germany. Paläontologische Zeitschrift, 84, 227 – 237.
Reich, M. 2005. The early fossil record and evolution of Holothuroidea
(Echinodermata: Echinozoa). In: Peng, S., Zhu, M., Li, G. & van
Iten, H. (eds) The Fourth International Symposium on the Cambrian
System, Nanjing, 8 –24 August 2005. Acta Micropaleontologica
Sinica, 22 (suppl.), 157 –159.
Reich, M. 2009. A critical review of octocorallian fossil record (Cnidaria:
Anthozoa). In: Smith, M. R., O’Brien, L. J. & Caron, J.-B. (eds)
International Conference on the Cambrian Explosion – Walcott
2009, 85.
Reich, M. 2010. The early evolution and diversification of holothurians
(Echinozoa). In: Harris, L. G., Böttger, S. A., Walker, C. W. &
Lesser, M. P. (eds) Echinoderms: Durham. Proceedings of the
12th International Echinoderm Conference, Durham, NH, 7 –11
August 2006. Taylor & Francis Group, London, 55 –59.
Robison, R. A. & Sprinkle, J. 1969. Ctenocystoidea: new class of primitive echinoderms. Science, 166, 1512–1514.
Rosen, B. R. & Smith, A. B. 1988. Tectonics from fossils? Analysis of
reef-coral and sea-urchin distributions from late Cretaceous to
Recent, using a new method. In: Audley-Charles, M. G. &
Hallam, A. (eds) Gondwana & Tethys. Geological Society,
London, Special Publications, 37, 275– 306.
Rozanov, A. YU. & Zhuravlev, A. YU. 1992. The Lower Cambrian
fossil record of the Soviet Union. In: Lipps, J. H. & Signor, P. W.
(eds) Origin and Early Evolution of the Metazoa. Plenum Press,
New York, 205– 282.
Rozhnov, S. V. 2006. Carpozoan echinoderms from the Middle Cambrian
(Mayaktakh Formation) of Siberia (lower reaches of the Lena River).
Paleontological Journal, 40, 266 – 275.
Rozhnov, S. V., Fedorov, A. B. & Sayutina, T. A. 1992. Lower Cambrian echinoderms from Russia. Paleontologicheskij zhurnal, 1992,
53 –66.
Schroeder, R. 1973. Carpoideen aus dem Mittelkambrium Nordspaniens.
Palaeontographica, Abteilung A, 141, 119 – 142.
Schuchert, C. 1919. A Lower Cambrian edrioasteroid Stromatocystites
walcotti. Smithsonian Miscellaneous Collections, 70, 1– 7.
Sdzuy, K. 1993. Early Cincta (Carpoidea) from the Middle Cambrian of
Spain. Beringeria, 8, 189– 209.
Sdzuy, K. 2000. Das Kambrium des Frankenwaldes. 3. Die Lippertsgrüner Schichten und ihre Fauna. Senckenbergiana lethaea, 79,
301 – 327.
Shinaq, R. & Elicki, O. 2007. The Cambrian sedimentary succession
from the Wadi Zerqa Ma’in (northeastern Dead Sea area, Jordan):
lithology and fossil content. Neues Jahrbuch für Geologie und
Paläontologie, Abhandlungen, 243, 255– 271.
Shu, D. G., Conway Morris, S., Han, J., Zhang, Z.-F. & Liu, J.-N.
2004. Ancestral echinoderms from the Chengjiang deposits of
China. Nature, 430, 422 – 429.
Shu, D. G., Conway Morris, S., Han, J., Zhang, Z.-F. & Han, J. 2010.
The earliest history of the deuterostomes: the importance of the
Chengjiang Fossil-Lagerstatte. Proceedings of the Biological
Society of Washington, 277, 165 –174.
Skovsted, C. B. & Peel, J. S. 2007. Small shelly fossils from the
argillaceous facies of the Lower Cambrian Forteau Formation of
western Newfoundland. Acta Palaeontologica Polonica, 52,
729 – 748.
Smith, A. B. 1982. The affinities of the Middle Cambrian Haplozoa (Echinodermata). Alcheringa, 6, 93 –99.
Smith, A. B. 1984. Classification of the Echinodermata. Palaeontology,
27, 431 – 459.
Smith, A. B. 1985. Cambrian eleutherozoan echinoderms and the early
diversification of edrioasteroids. Palaeontology, 28, 715 –756.
Smith, A. B. 1988. Patterns of diversification and extinction in Early
Palaeozoic echinoderms. Palaeontology, 31, 799 – 828.
Smith, A. B. 2004. Echinoderm roots. Nature, 430, 411– 412.
Smith, A. B. 2005. The pre-radial history of echinoderms. Geological
Journal, 40, 255– 280.
Smith, A. B. 2008. Deuterostomes in a twist: the origins of a radical new
body plan. Evolution and Development, 10, 493 –503.
Smith, A. B. & Jell, P. A. 1990. Cambrian edrioasteroids from Australia
and the origin of starfishes. Memoirs of the Queensland Museum, 28,
715 – 778.
Smith, A. B. & Jell, P. A. 1999. A new cornute carpoid from the Upper
Cambrian (Idamean) of Queensland. Memoirs of the Queensland
Museum, 43, 341 – 350.
Smith, A. B. & Zamora, S. 2009. Rooting phylogenies of problematic
fossil taxa; a case study using cinctans (stem-group echinoderms).
Palaeontology, 52, 803 – 821.
Spencer, R. J. & Demicco, R. V. 2002. Facies and sequence stratigraphy
of two Cambrian grand cycles: implications for Cambrian sea level
and origin of grand cycles. Bulletin of Canadian Petroleum
Geology, 50, 478 –491.
Sprinkle, J. 1973. Morphology and Evolution of Blastozoan Echinoderms. Harvard University Museum of Comparative Zoology, Cambridge, MA, Special Publication, 1 –283.
Sprinkle, J. 1985. New Edrioasteroid from the Middle Cambrian of
western Utah. University of Kansas, Paleontological Contributions,
Papers, 116, 1 –4.
Sprinkle, J. 1992. Chapter 11. Radiation of Echinodermata. In: Lipps,
J. H. & Signor, P. W. (eds) Origin and Early Evolution of the
Metazoa. Plenum Press, New York, 375 – 398.
Sprinkle, J. & Collins, D. 1998. Revision of Echmatocrinus from the
Middle Cambrian Burgess Shale of British Columbia. Lethaia, 31,
269 – 282.
Sprinkle, J. & Collins, D. 2006. New eocrinoids from the Burgess Shale,
southern British Columbia, Canada, and the Spence Shale, northern
Utah, USA. Canadian Journal of Earth Sciences, 43, 303 –322.
Sprinkle, J. & Collins, D. 2011. What is Echmatocrinus from the
Burgess Shale: a crinoid precursor in the echinoderms or an octocoral
in the cnidarians? In: Johnston, P. A. & Johnston, K. J. (eds) Proceedings of the International Conference on the Cambrian Explosion
(ICCE). Palaeontographica Canadiana, 31, 169 –176.
Sprinkle, J. & Wilbur, B. C. 2005. Deconstructing helicoplacoids: revising the most enigmatic Cambrian echinoderms. Geological Journal,
40, 281 – 293.
Sprinkle, J., Parsley, R. L., Zhao, Y.-L. & Peng, J. 2011. Revision of
lyracystid eocrinoids from the Middle Cambrian of South China and
western Laurentia. Journal of Paleontology, 85, 250 – 255.
Sumrall, C. D. 1997. The role of fossils in the phylogenetic reconstruction of Echinodermata. Paleontological Society Papers, 3, 267 – 288.
Sumrall, C. D. & Sprinkle, J. 1999. Ponticulocarpus, a new cornutegrade stylophoran from the Middle Cambrian Spence Shale of
Utah. Journal of Paleontology, 73, 886– 891.
Sumrall, C. D., Sprinkle, J. & Guensburg, T. E. 1997. Systematics and
paleoecology of Late Cambrian echinoderms from the western United
States. Journal of Paleontology, 71, 1091–1109.
Sumrall, C. D., Koverman, K. S. & Rozhnov, S. 2003. Where is the
missing Cambrian echinoderm diversity – evidence from Arctic
Siberia. Geological Society of America Abstracts with Programs,
35, 17.
Sumrall, C. D., Sprinkle, J., Pruss, S. & Finnegan, S. 2009. Cardiocystella, a new cornute stylophoran from the Upper Cambrian
Whipple Cave Formation, eastern Nevada, USA. Journal of Paleontology, 83, 307 – 312.
Swalla, B. J. & Smith, A. B. 2008. Deciphering deuterostome phylogeny: molecular, morphological and palaeontological perspectives.
Downloaded from http://mem.lyellcollection.org/ by guest on November 27, 2013
CAMBRIAN ECHINODERMS
Philosophical Transactions of the Royal Society of London B, 363,
1557– 1568.
Termier, H. & Termier, G. 1973. Les échinodermes Cincta du Cambrien
de la Montagne Noire (France). Geobios, 6, 243 –266.
Ubaghs, G. 1953. Notes sur Lichenoides priscus Barrande, eocrinoı̈de du
Cambrien Moyen de la Tchécoslovaquie. Institut royal des Sciences
naturelles de Belgique, 29, 1– 24.
Ubaghs, G. 1967. Le Genre Ceratocystis Jaekel (Echinodermata, Stylophora). University of Kansas, Paleontological Contributions,
Papers, 22, 1 –16.
Ubaghs, G. 1968a. Eocrinoidea. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology, Part S, Echinodermata 1, 2. Geological Society
of America, New York & University of Kansas, Lawrence, KS,
S455– S495.
Ubaghs, G. 1968b. Stylophora. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology, Part S, Echinodermata 1, 2, Geological Society
of America, Boulder, CO & University of Kansas, Lawrence, KS,
S495– S565.
Ubaghs, G. 1971. Diversité et spécialisation des plus anciens échinodermes que l’on connaisse. Biological Reviews, 46, 157 –200.
Ubaghs, G. 1975. Early Palaeozoic echinoderms. Annual Review of Earth
and Planetary Sciences, 3, 79 –98.
Ubaghs, G. 1987. Echinodermes nouveaux du Cambrien moyen de la
Montagne Noire (France). Annales de Paléontologie, 73, 1– 27.
Ubaghs, G. 1998. Echinodermes nouveaux du Cambrien supérieur de la
Montagne Noire. Geobios, 31, 809 –829.
Ubaghs, G. & Robison, R. A. 1985. A new homoiostelean and a new
eocrinoid from the Middle Cambrian of Utah. University of Kansas
Paleontological Contributions, Papers, 115, 1 –24.
Ubaghs, G. & Robison, R. A. 1988. Homalozoan Echinoderms of the
wheeler formation (Middle Cambrian) of western Utah. University
of Kansas, Lawrence, KS, Paleontological Contributions, Papers,
120, 1– 17.
Ubaghs, G. & Vizcaı̈no, D. 1990. A new eocrinoid from the Lower Cambrian of Spain. Palaeontology, 33, 259 –256.
Walcott, C. D. 1911. Cambrian geology and paleontology. II.
No. 3. Middle Cambrian holothurians and medusa. Smithsonian Miscellaneous Collections, 57, 42– 68.
Wilbur, B. C. 2006. Reduction in the number of Early Cambrian helicoplacoid species. Palaeoworld, 15, 283 –293.
Zamora, S. 2010. Middle Cambrian echinoderms from North Spain show
echinoderms diversified earlier in Gondwana. Geology, 38, 507 – 510.
Zamora, S. 2011. Equinodermos del Cámbrico de España: situación
actual de las investigaciones y perspectivas futuras. Estudios Geológicos, 67, 59 – 81.
171
´ lvaro, J. J. 2010. Testing for a decline in diversity prior to
Zamora, S. & A
extinction: Languedocian (latest Mid-Cambrian) distribution of Cinctans (Echinodermata) in the Iberian Chains, NE Spain. Palaeontology, 53, 1349–1368.
Zamora, S. & Rahman, I. A. 2008. Nuevos datos sobre el género Sucocystis (Cincta, Echinodermata) en el Cámbrico medio de España:
Implicaciones biostratigráficas y filogenéticas. Revista Española de
Paleontologı́a, 23, 301– 313.
Zamora, S. & Smith, A. B. 2008. A new Middle Cambrian stemgroup echinoderm from Spain: Palaeobiological implications of
a highly asymmetric cinctan. Acta Paleontologica Polonica, 53,
207– 220.
Zamora, S. & Smith, A. B. 2010. The oldest isorophid edrioasteroid
(Echinodermata) and the evolution of attachment strategies in
Cambrian edrioasteroids. Acta Palaeontologica Polonica, 55,
487– 494.
Zamora, S. & Smith, A. B. 2012. Cambrian stalked echinoderms
show unexpected plasticity of arm construction. Proceedings of the
Royal Society of London, B, 279, 293 – 298, http://dx.doi.org/10.
1098/rspb.2011.0777
Zamora, S., Liñán, E., Gámez Vintaned, J. A., Domı́nguez Alonso, P.
& Gozalo, R. 2007a. Nuevo carpoideo de la clase Cincta Jaekel,
1918 del norte de España: inferencias sobre la morfologı́a funcional
del opérculo. Ameghiniana, 44, 727 –738.
Zamora, S., Liñán, E., Domı́nguez Alonso, P., Gozalo, R. & Gámez
Vintaned, J. A. 2007b. A Middle Cambrian edrioasteroid from the
Murero biota (NE Spain) with Australian affinities. Annales de
Paléontologie, 93, 249– 260.
Zamora, S., Gozalo, R. & Liñán, E. 2009. Middle Cambrian gogiids
(Eocrinoidea, Echinodermata) from Northeast Spain: Taxonomy,
palaeoecology and palaeogeographic implications. Acta Paleontologica Polonica, 54, 253 – 265.
´ lvaro, J. J. & Smith, A. B. 2010.
Zamora, S., Clausen, S., A
Pelmatozoan echinoderms as colonizers of carbonate firmgrounds
in mid –Cambrian high energy environments. Palaios, 25, 764– 768.
Zhao, Y. L., Parsley, R. L. & Peng, J. 2007. Early Cambrian echinoderms from Guizhou Province, South China. Palaeogeography,
Palaeoclimatology, Palaeoecology, 254, 317– 327.
Zhao, Y. L., Parsley, R. L. & Peng, J. 2008. Basal Middle Cambrian
short-stalked eocrinoids from the Kaili Biota: Guizhou Province,
China. Journal of Paleontology, 82, 415 –422.
Zhao, Y. L., Sumrall, C., Parsley, R. L. & Peng, J. 2010. Kailidiscus, a
new plesiomorphic edrioasteroid from the basal Middle Cambrian
Kaili Biota of Guizhou Province, China. Journal of Paleontology,
84, 668– 680.