&logzcalJournnl
ofthe Lznnean Sociely (2000), 129: 1 I
I 128. L2'ith 2 figures
Historical biogeography and ecology of a
Continental Antarctic mite genus, Maudheimia
(Acari, Oribatida): evidence for a Gondwanan
origin and Pliocene-Pleistocene speciation
DAVID J. MARSHALL*
Department o f ~ o o l o g y ,UniversiQ of Durban- Pbistville P/Bag x 54001, Durban 4000,
South i f ~ c a
LOUISE COETZEE
National Museum, Bloemfontein, South Afica
Received Januay 1999; arceptrdfor publication Aiy 1999
Of the eight genera (30 species) of extant Acari in Continental (=East) Antarctica, the genus
Maudheimia Dalenius & Wilson, 1958 (Orihatida; Maudheimiidae) is uniquely endemic. A
Gondwanan origin is proposed for the genus based on antiquity, inferred from endemism,
a widespread distribution throughout Continental Antarctica and a limited dispersal capacity.
Adaptation for a high montane epilithic existence, a necessity for the origination and longterm persistence in Antarctica, is inferred from the life history, physiology and ecology of
Maudheirnia. Phylogenetic analysis placed all four Maudheimia species in a single (generic) clade
tanngardenensii Coctzee, 1997 (M.
with the following structure (&I. petronia Wallwork, 1962 (M.
mar.rhalli Coetzee, 1997 (M. wilsoni Dalenius & Wilson, 1958)))).Geographical distributions
of the ibiuudheirnia species, in relation to their phylogenetic relationships, support the hypothesis
that post-Gondwanan speciation occurred as a consequence of isolation during glaciation of
Antarctica.
0 2000 The Linnran Society of Lcrndon
ADDITIONAL KEY WORDS:-Acari
dheimia - origin phylogeny.
~
Antarctica
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biogeography
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endemism
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iMau-
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CONTENIS
Introduction . . . . . . . . . . . . . . . . . . . .
Material and methods
. . . . . . . . . . . . . . .
Description of characters . . . . . . . . . . . . .
Results . . . . . . . . . . . . . . . . . . . . .
Discussion . . . . . . . . . . . . . . . . . . . .
Dispersal potential: Maudheirnia compared to other invertebrates
* Corresponding author.
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E-mail: [email protected]
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0 2000 The Linnean S(iciety of I,ond(in
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D . J . MARSHALL AND L. COETZEE
Geographical distribution of Maudhezmia . . . . . . . . . .
Ecology: local distribution and abundance . . . . . . . . .
Ecology: adaptations for an epilithic existence in continental Antarctica
Speciation . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . .
Acknowledgements
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References . . . . . . . . . . . . . . . . . . . . . .
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INTRODUCTION
Continental Antarctica supports an impoverished biota. This is largely the result
of demolition of habitat and large-scale species extinction, through glaciation and
the formation of the East Antarctic ice sheet. The remaining, free-living, terrestrial
Antarctic fauna is represented only by invertebrate phyla (Arthropoda, Tardigrada,
Rotifera, Nematoda and Protozoa). Little is known about the biogeographical origin,
level of endemism, or potential for immigration of most species representing these
phyla (Marshall & Pugh, 1996; McInnes & Pugh, 1998). Biogeographical information
for the continental Antarctic arthropods is limited to descriptive distribution lists
(Dalenius, 1965; Gressitt, 1965; Wallwork, 1973). While dispersal and colonization
are often discussed with regard to the distribution of the continent's biota (see
Walton, 1990), little consideration has been given to their historical isolation.
The oribatid mite genus Maudheimia Dalenius & Wilson, 1958 (Oribatida; Maudheimiidae) is represented in the continent by four species: M. wilsoni Dalenius &
Wilson, 1958, M. petronia Wallwork, 1962, M. marshalli Coetzee, 1997 and M.
tanngardenensis Coetzee, 1997. Along with Antarcticola meyen' Wallwork, 1967, they are
the only Oribatida existent in Continental Antarctica, of approximately 7000 known
global oribatid mite species. The balance of the continent's mites comprises 25
species of Prostigmata (Marshall & Pugh, 1996). In addition, the genus and family
(Maudheimia and Maudheimiidae) are the only supra-specific endemic acarine taxa
to the region (Dalenius & Wilson, 1958; Wallwork, 1967; Ohyama & Hiruta, 1995;
Marshall & Pugh, 1996; Coetzee, 1997). All other genera have maritime and/or
sub-Antarctic affinities. Antarcticola mTeri Wallwork 1967, found coastally at western
Enderby Land (40" E-50" E; Sugawara, Ohyama & Higashi, 1995), has a sister
species on South Georgia and Kerguelen (see Pugh, 1993).
Maudheimia was established for M. wilsoni by Dalenius & Wilson (1958), and
Wallwork (1962) subsequently described M. petronia. The genus was initially thought
to be closely-related to Scheloribates (Scheloribatidae; Dalenius & Wilson, 1958;
Wallwork, 1973), but the two genera are readily differentiated on octotaxic organs;
Maudheimia possesses porose areas instead of sacculi. Balogh & Balogh (1 984, 1992)
proposed a new family Maudheimiidae, within the superfamily Oripodoidea. Coetzee
(1997) recently described M. marshalli and M. tanngardenensis,and supported recognition
of the family, but moved it to the superfamily Ceratozetoidea.
This study considers two hypotheses. First, that Maudheimia existed in Antarctica
prior to the continent's separation from the rest of Gondwana. Second, that speciation
of the extant Maudheimia species is post-Gondwanan, resulting from isolation, largely
affected by glaciation of the continent. These hypotheses are examined using an
integrative approach, which considers the phylogeny, biogeography and ecology of
the Maudheimia species. In addition to presenting the first phylogeny for an antarctic
GONDWANAN ORIGIN FOR ,ZfAUDHEfJfIA
I13
mite taxon, this is only the second study presenting evidence for the Gondwanan
origin of a Continental Antarctic taxon (see Bayly, 1994).
MATERIAL AND hlETHODS
The four species of Maudheimia were subjected to phylogenetic analysis. Specimens
from nine localities across Antarctica were obtained, as part of a re-evaluation of
the genus (Coetzee, 1996, 1997). Material included the type specimens of all four
Maudheimia species. Outgroups were selected from the Oripodoidea and Ceratozetoidea, putative superfamilies of Maudheimia. Ceratozetoid taxa included the familial
type species, Ceratozetes gracilis (Michael, 1884), and representatives of four (of the
five) genera of Sphaerozetinae, Fuscozetes sellnicki Hammer, 1952, Melanozetes longisetosus
Hammer, 1952, Sphaerozetes arcticus Hammer, 1952 and the Antarctic, Edwardzetes
australis Starji & Block, 1995. The oripodoid species selected included the subAntarctic Dometorina marionensis Van Pletzen & Kok, 1971 , agoribatula subantarctica
Van Pletzen & Kok, 1971 and Scheloribatesjagellatus Wallwork, 1966.
Character states of the Maudheimia species, agoiibatula subantarctica and Dometorina
marionensis, were determined from preserved material housed in the acarology
collection of the National Museum, Bloemfontein, South Africa. Character states
for Ceratozetes gracilis, Fuscozetes sellnicki, Melanozetes longisetosus, Sphaerozetes arcticus,
Edwardzetes australis and Scheloribates jagellatus refer to Behan-Pelletier (1985), Menke
(1964), Start & Block (1995))and Wallwork (1966). Three data sets were prepared,
with outgroups being the Oripodoidea species, the Ceratozetoidea species, and the
species of both these superfamilies. Analyses were performed using PAUP 3.1.1
(Swofford, 1993) with the Heuristic search and Bootstrap options.
Description
of characters
1. Rostrum shape: the rostrum is commonly rounded, but often modified developing a medial point or lateral teeth. O=rounded, 1 =with medial point, 2 =
with lateral teeth.
2. Anterior prodorsal shape: anterior part of prodorsum may be wide or attenuated. 0 =prodorsum anteriorly attenuated, 1 = prodorsum anteriorly wide.
3. Genal tooth: a lateral incision in the rostra1 border forming a free tooth with
variable shape and size (Grandjean, 1952). O=genal tooth absent, 1 =genal tooth
pointed, 2 = genal tooth truncate.
4. Shape of lamellae: these cuticular, dorsal outgrowths of the prodorsum,
functioning to protect the withdrawn anterior legs (Evans, 1992), are variable in
shape and size (Travt et al., 1996).0 =lamellae forming narrow ridges, not prominent,
1 = lamellae broad, lamelliform (blade- or flange-like).
5. Translamella: the connecting ridge joining the distal ends of the lamellae
(Travt et al., 1996). 0 = translamella absent, 1 = translamella present.
6. Lamellar cusps: lamellae may terminate in a free, tooth-like cusp, variable in
shape and size (Travi: et al., 1996). 0 =lamellar cusps absent, 1 =lamellar cusps
present.
7. Insertion of lamellar setae: these superfamilies usually have lamellar setae
114
D. J. MARSHALL AND I.. COETZEE
inserted on the lamellar apices or the cusps, rarely on the prodorsal surface. O =
inserted on cusps, 1 =inserted posteriorly to cusps, on prodorsal surface.
8. Tutorium: this cuticular outgrowth, situated laterally to (or beneath) the
lamellae, like the lamellae, protects the distal part of leg I (Grandjean, 1952). It can
be ridged or lamelliform. 0 = tutorium absent, 1 = tutorium ridge-shaped, 2 =
tutorium lamelliform.
9. Free cusp on tutorium: when present, the tutorium may possess a distal, toothlike cusp. 0 = tutorium absent, 1 = free cusp absent, 2 = free cusp present.
10. Shape of tutorium: here reference is made to the attachment of the tutorium
to the prodorsum, and not the free standing ‘blade’. This may be short, slightly
curved and not reaching the rostral border, or long, semi-circular and reaching the
rostral border, irrespective of blade size. 0 = tutorium absent, 1 = tutorium short,
slightly curved, 2 = tutorium long, semi-circular.
1 1. Pedotectum I: this is a lamelliform outgrowth behind leg I, directed anteriorly
and protecting the proximal articulations of the leg (Grandjean, 1952). 0 =pedotectum I narrow, not dorsally prolonged, l = pedotectum I wide, dorsally prolonged
towards bothridium.
12. Axillary saccule: a porose cuticular invagination opening on the infracapitulum, immediately paraxial to the insertion of the pedipalp (Norton & BehanPelletier, 1986; Norton et al., 1997). 0 = axillary saccule absent, 1 = axillary saccule
present.
13. Bothridial scales: sclerotized ‘scales’ may be associated with the usually cupshaped bothridium (Menke, 1963, 1964; Behan-Pelletier, 1984, 1985). 0 = bothridial
scales absent, 1 =bothridial scales present.
14. Bothridial opening: although usually a closed rounded cup, the bothridium
may possess a lateral opening. 0 = bothridium with or without scales, but closed,
1 =bothridium with scales and lateral opening.
15. Bothridial covering: the bothridium may be uncovered, partly covered, or
completely covered by the anterior border of the notogaster or by the anterior edges
of the pteromorphs. 0 = bothridium partly covered, 1 = bothridium completely
covered.
16. Anterior tectum: the anterior border of the notogaster may have a free edge
connecting the pteromorphs and extending to varying degrees over the posterior
part of the prodorsum. 0 =anterior tectum absent, 1 =anterior tectum present.
17. Cuticle: sclerotization in oribatid mites is variable in degree (Alberti, Storch
& Renner, 1981; Pugh, King & Fordy, 1987). 0 =well sclerotized, hard cuticle, 1 =
weakly sclerotized, leathery cuticle.
18-20. The notogastral setae, el, c? and the d-series are ofphylogenetic importance
(Grandjean, 1949; Seniczak, Behan-Pelletier & Solhmy, 1990; Travi. et al., 1996).
Primitively, all these setae are present, with loss occurring in derived forms. 18. 0 =
seta c/ present, 1 = seta c! absent; 19. 0 = seta c, present, 1 = seta c, absent; 20. 0 =
d-series present, 1 = d-series absent.
21. Octotaxic organs: in oribatid mites the octotaxic system comprises concentrations of pores in the cuticle, known as porose areas. These may become
invaginated forming sacculi (Norton et al., 1997). 0 =porose areas, 1 = sacculi.
22. Size of octotaxic organs: 0 = octotaxic organs not minute, 1 = octotaxic organs
minute.
23. Lenticulus: a distinct, unpaired, transparent area within the cuticle, located
antero-dorsally on the notogaster. It is a secondarily developed photoreceptor organ
GONDWANAN ORIGIN FOR .M4CrDHEIA11A
I I5
(Alberti & Fernandez, 1990; Alberti, Kaiser & Fernandez, 1991). 0 = lenticulus
absent, 1 =lenticulus present.
24. Postanal porose area: an unpaired porose area, posterodorsal to the anal
plates, and slightly removed from the circumgastric scissure (Norton et al., 1997).
This differs from the marginoventral series of porose areas which form a narrow
band adjacent to the soft cuticle of the circumgastric scissure. These small porose
areas may fuse to form a narrow ribbon of porosity, as in Z’ygoribatula, which is not
homologous to the postanal porose area (Grobler, 1993; Norton et al., 1997). O =
postanal porose area absent, 1 =postanal porose area present.
25, 26. Shape and size of pteromorphs: cuticular, anterolateral outgrowths of the
notogaster forming wing-like expansions for protection of the legs. Primitively, small
and horizontal, becoming large and ventrally curved in the more derived forms.
Ultimately are hinged, permitting movement (Woodring, 1962; Evans, 1992). 25.
Pteromorph shape. 0 = short, horizontal, 1 =long, curved ventrally; 26. Pteromorph
orientation and size. 0 = anterolateral corners directed posteriorly, pteromorphs
small, 1 = anterolateral corners directed anteriorly, pteromorphs large.
27. Sejugal apodeme: internal, transverse laminae (or extensions) of the anterior
and posterior borders of each podosomal segment ( = epimeres, see 28). The apodeme
between epimeres I1 and I11 is the sejugal apodeme. Apodemes are not formed
secondarily, but rather are lost during the course of evolution (Grandjean, 1952;
Evans, 1992). 0 = sejugal apodeme continuous, 1 = sejugal apodeme reduced.
28. Number of setae on epimere 111: epimeres form from the exoskeleton
surrounding the acetabula and extend medially (paraxially). They represent podosomal segments. There is ontogenetic variation in epimeral setae, with those setae
appearing in the later ontogenetic stages (3, and 4,) being more susceptible to
evolutionary loss (Grandjean, 1934). 0 = seta 3, present on epimere 111, 1 = seta 3,
absent on epimere 111.
29. Custodium: a pointed, cuticular process, attached to the body in the vicinity
of leg I11 and always directed anteriorly (Grandjean, 1952). 0 =custodium absent,
1 = custodium present.
30. Number of setae on genital plates: genital setal number is an important
taxonomic character in oribatid mites. Adults of higher oribatid mites nominally
have six pairs (Grandjean, 1949). 0 = 6 setae on each genital plate, 1 = 4 setae on
each genital plate.
3 1. Size of genital plates in females: 0 =female genital plates smaller or equal to
anal plates, 1 =female genital plates larger than anal plates.
32. Pre-anal organ (shape): An internal porose organ associated with the preanal sclerite, lies anteriorly of the anal opening. The ano-genital muscles originate
from this organ (Norton et al., 1997), which is variable in shape and size. O=stem
of pre-anal organ short and wide, 1 =stem of pre-anal organ long and narrow.
33. Ventral carinae on femurs: lamelliform cuticular outgrowths on the ventral
sides of all or some of the femurs, for protection of the legs. O=ventral carinae
absent or small and insignificant, 1 =ventral carinae present, broad, prominent.
34. Solenidion I on tarsus I: the ‘normal’ position for this solenidion is near 2
and the famulus, and it usually forms part of the tarsal cluster (Grandjean, 1935;
Norton, 1977). Distal displacement towards the tectal setae is unusual (BehanPelletier, 1985). 0 = inserted near solenidion 2 and famulus, 1 = displaced distally to
vicinity of tectal setae.
35. Number of setae on femur 111: very often there are 3 setae on femur 111, viz.
116
I). J . MARSHALL AND L. COETZEE
d (dorsal), I’ (antiaxial lateral) and v’ (antiaxial ventral) (Travt et al., 1996). The loss
of seta 1’ has been reported in some ceratozetid species (Behan-Pelletier, 1986). 0 =
seta I’ present (3 setae), 1 =seta I’ absent (2 setae).
36. Shape of antiaxial ventral setae v” on tibia I and 11: normally these setae are
setiform and similar to the other leg setae, but may also be spinous, thickened and
distally tapered (Behan-Pelletier, 1986). 0 = setae v” on tibia I and I1 not spinous,
1 =setae v” on tibia I and I1 spinous.
37. Length of antiaxial fastigial setaft” on tarsus I: the fastigial setae (ft) occur
dorsally on the tarsus, usually near the solenidia 1 and 2 (Grandjean, 1940; Norton,
1977; Travi. et al., 1996). O=setaft” more or less the same length as$’, 1 =sets$''
much shorter and thinner than$‘.
38. Humeral organ: a porose organ, usually papilliform, sometimes present in
immatures, and situated just behind the sejugal furrow and antero-lateral to seta c.,
The organ may form a porose disk-like sclerite (Grandjean, 195 1; Norton et al.,
1997). 0 = humeral organ absent, 1 = humeral organ papilliform, 2 = humeral organ
a porose disk.
39. Humeral sclerite bearing gastronotal seta c,: a subtriangular, micropunctate
sclerite carrying seta c,, situated in the humeral region of immatures (Behan-Pelletier,
1985, 1986). 0 = humeral sclerite absent, 1 = humeral sclerite present.
40. Gastronotal porose sclerites: the gastronotal area of higher oribatid mite
immature stages commonly have porose sclerites (areas) in various forms viz.
microsclerites bearing (or without) gastronotal setae (excentrosclerites), or macrosclerites bearing gastronotal setae, or a mixture of these forms (Grandjean, 1953,
1963, 1970; Behan-Pelletier, 1984; Norton et al., 1997). 0 = microsclerites with setae,
1 = macrosclerites alone, or with microsclerites not associated with setae, 2 =macroand microsclerites associated with setae.
RESULTS
The analysis using only the oripodoid genera as the outgroup showed 3 1 characters
common to Maudheimia and the outgroup species (Table 1).Three trees are retained,
and the bootstrap 50% majority-rule consensus tree consisted of 40 steps, with a
consistency index of 0.8, and a homoplasy index of 0.2. Topology of the ingroup is the
same as that when using both superfamilies (Fig. l), and the outgroup is unresolved. A
bootstrap value of 100 is attained for the branch leading to the ingroup.
The analysis using the cerozetoid genera as outgroups, showed 29 common
characters (Table 1). One tree is retained, and the bootstrap 50% majority-rule
consensus tree consists of 36 steps, with a consistency index of 0.806 and homoplasy
index of 0.194. Again the topology of the ingroup is the same as the tree in Figure
1, but the outgroups S. arcticus and E. australis are switched and the tree is fully
resolved. A bootstrap value of 100 is attained for the branch leading to the ingroup.
The analysis including the species from both the superfamilies, includes all 40
characters (Fig. 1; Table 1). One tree is retained. The length of the bootstrap 50%
majority-rule consensus tree is 66, the consistency index 0.7 12, and the homoplasy
index 0.288. The bootstrap value of the branch leading to the Oripodoidea outgroup
is 100, to the Ceratozetoidea outgroup is 98 and to the ingroup (Maudheimia) is 99.
The phylogcnetic analysis indicates that Maudheimia is a monophyletic group,
GONDWANAN ORIGIN FOR hlilUDHELZILA
h
W
L n
*
M
N
117
118
D. J. MARSHALL AND L. COETZEE
Figure 1. Cladogram depicting hypothesis for the evolution of Maudheimia species. (0)
state 0; ( 0 )
state 1; (m) state 2. The character states on the terminal branches are indicated by letters as follows:
A=18, 19, 20; B=25; C=35; D = 5 , 19, 33, 39; E = l ; F=23, 24, 36; G=19, 20; H = 3 ; I=5, 18;
5 ~ 3 3K
; = l ; L=28, 35; M=25; N = l ; 0 = 4 , 33; P=28; Q=15, 19, 20, 27, 37; R=5; S=21.
Bootstrap values are indicated in rectangles.
separated from the other ceratozetoid genera by 11 synapomorphies, namely, a
wide, rounded prodorsum (2), ridged lamellae (4), ridged tutorium (8), absence of
the free cusp on tutorium (9), lateral opening of bothridium (14), weakly sclerotized
cuticle (17), minute octotaxic porose areas (22), extraordinary large genital opening
of females (31), absence of femoral carinae (33), disk-shaped humeral organ in
immatures (38) and the presence of macro- and seta-bearing microsclerites in
immatures (40). Most of these attributes indicate a reduction in size or loss of
structure, particularly those referring to the lamellae, tutoria, tutorial cusp, femoral
carinae and sclerotization of the cuticle.
The loss of seta 1’ on femur I11 (character 35) of M. petronia is an autapomorphy
for the species, but also occurs in E. australis. The insertion of the lamellar seta
(character 7), posteriorly to lamellar apex, is a synapomorphy for M. tanngardenensis,
M. marshalli and M. wilsoni. The short horizontal pteromorphs (character 25) of M.
tanngardenensis, and the presence of setae c, c,? and d-series (characters 18, 19 and 20)
in M. marshalli, both represent autapomorphies for these species respectively and
reversal to the primitive state. The long semi-circular shape of the tutorium is a
synapomorphy for M. marshalli and M. wilsoni.
DISCUSSION
Dispersal potential: Maudheimia compared to other invertebrates
Geographic distribution is the result of dispersal or vicariance, or some combination
of the two (Myers & Giller, 1988). Where dispersal is considered to be prominent
GONIIWANAN ORIGIN FOR MIUDHEfAlIA
119
in distribution, this should be apparent from the biota's potential for dispersal, its
dispersal mechanism, and the distribution pattern itself, notwithstanding other
features such as the capacity for re-colonization. Wind may be the most important
dispersal agent of Continental Antarctic microbiota (see Walton, 1990; Seppelt,
1995; Broady, 1996). Whereas both man and birds may currently affect limited
dispersal of invertebrates in the continental region, they cannot be considered
primary dispersal agents. Many Antarctic plants and invertebrates have evolved
propagules suitable for wind dispersal (see Ellis-Evans & Walton, 1990; Walton,
1990). The efficacy of these depends on attributes of size (for example, less than
100pm), weight, abundance of production (for example, thousands per lifecycle;
Walton, 1990) and, physiological resistance to low temperature and desiccation.
The major terrestrial Antarctic invertebrate phyla (Protozoa, Nematoda, Rotifera
and Tardigrada), with the exception of the Arthropoda, have propagules conforming
to this general trend.
Many Antarctic invertebrates, excluding arthropods, are anhydrobiotic and/or
cryptobiotic, which enhances their dispersal capacity. The arthropods (including
Maudheimia) are not physiologically equipped for present-day aerial dispersal across
the continent. In contrast to rotifers, tardigrades and nematodes, which colonize
upon settling in favourable habitat, Antarctic arthropods behaviourally select habitat
to match their relatively moderate physiological capabilities. The life history characteristics of Maudheimia further constrain dispersal. These include low fecundity
(two to four eggs per female per five-year period), compact juvenile aggregations,
and the cementation of eggs to surfaces (Marshall & Convey, 1999). The efficacy
of rotifer and tardigrade Antarctic dispersal is suggested by the circumpolar distribution of some species (see Marshall et al., 1995h; McInnes & Pugh, 1998). With
the exception of Nanorchestes antarcticus Strandtmann, 1963 (Prostigmata), arthropods
do not show circumpolar distributions (Wise & Gressitt, 1965; Pugh, 1993; Greenslade, 1995;Judson, 1995; Frati et al., 1997; Convey, Greenslade & Pugh, 2000).
Geographical distribution of Maudheimia
Collectively, Maudheimia is circumpolarly distributed in Antarctica (Fig. 2; Table
2). It ranges from Victoria Land (1 70"E), to the Ahlmannryggen ( loow) in western
Dronning Maud Land; M. petronia being the sole species in Victoria Land
(170-16OoE), with the others occurring in Dronning Maud Land (DML; 10OW30"E). The Maudheimia species exhibit non-overIapping, allopatric distributions: M.
wilsoni is restricted to the Ahlmannryggen range, M. marshalli extends across the H U
Sverdrupfjella, the Gjelsvikfjella and the Muhlig-Hoffmanfjella, and M. tanngardenensis
occurs on Tanngarden, a western nunatak of the Sm-Rondane range (Fig. 2, Table
2). Distributions of the DML species are delimited by three large glaciers (see Fig.
2): the Jutelstraumen, between the Ahlmannryggen and the HU Sverdrupfjella
ranges, the H.E. Hansenbreen glacier, at the western border of the Sur-Rondane
range, and the Byrdbreen glacier at the eastern border of this range. Separation of
the DML species typifies a barrier effect by these glaciers.
Disjunction in the continental distribution of Maudheimia in DML and Victoria
Land is the likely result of these regions being isolated during extensive glaciation
of the eastern Antarctic sectors, Enderby and Wilkes (30-150"E; see Goodwin, 1993;
the present day oases at Vestfold Hills, Bunger Hills and Windmill Islands were
120
D. ,J. hlARSHALL AND I,. C:OEl’ZEE
A
0”
I
Figure 2. A, continental distributions of the iilandhrirma species: 1\1. wilsoni (Mw), M. mal:hdli (hlm),
‘11. tunngurdmensis (hlt) and hl. pttronia (Mp). B, mountain ranges (A)
in Dronning blaud Land on which
the Aluudlleimia species are found, and prominent glaciers ( x ) in the region: Ahlmannryggen (Ah),
Jutelstraumrn (Ju), H.U. SverdrupGella, Gjclsviktjclla and R.luhlig-HoffmannfJella (SGhI), H.-E.
Hansenbreen (Ha), Snr-Roiidane (SR),Byrdhreen (By).
completely covered during the last glacial maxima, 1 1 000 ya; Ingolfsson et al., 1998).
Low acarine diversities and disharmonic, poorly-associated faunas fiirther reflect the
glaciation extent of these sectors. The number of free-living acarine species in Maud,
Scott, Enderby and Wilkes sectors (re: Pugh, 1993), as a percentage of the total is,
respectively, 27%, 51%, 149’0 and 8%. Furthermore, Enderby and Wilkes show
zero association with the maritime/continental Antarctic acarofauna, even at the
family level (Marshall & Pugh, 1996), suggesting colonization from the sub-Antarctic.
The region below the polar plateau in the Byrd and R o m e sectors to the west
remains heavily glaciated due to its close polar proximity, currently isolating ‘western’
Antarctica. Iiitracontinental dispersal of most acarine species probably ceased at the
GONDLVANAN ORIGIN FOR .LfJ LDHELLfL4
121
TABLE
2. Records of ,Iluudhezmza in continental Antarctica
Sprcirs
Rqions/localities
ill. Icilxnii
Lhonning hlaud Land
.4hlniannygqen:
I'assat/Borras (7 1"18'S, O+oU3'\.Vj
Ro1)ertskollen group (7 I"28'S. 03'15'Lq
Af. marshalh
.If. tanrigardenesis
'14, petmnia
Straumsnutane (7 I"36'S. 01°47'L%J
Johnshrotet (7 1"20'S, 04°10'W~
H . c;. .Scvrdni~fiella:(7 2-7 3 5 ,
0030'LV- 0 1030%)
Vendeholten
Romlingane, Tua, Brekkerista, Tt,ora
Cjerllikfiellfl:
Jutelsewm (72'03'S, U2'+0'Ej
A liihl(q-Ha'inannjella:
I'logskaftet (7 1'50'S. 05'1 5%)
Svarthamarrn (7 1"55'S, 05°10'E)
Elitxrget (=~Jutulrora)
Sor Rondanr: ( 7 2 5 , 22"- 28%)
Tatingarden (72"S, 23"Ej
Victoria Land
Hallrt Glacier (72'5, 170%)
Redcastle Ridge
Reference articles
Dalenius & Wilson (1958), Gressitt (1965),
Dalenius ( I 965), Gressitt & Shoup (1 967),
Wallwork (1967, 1973), Coetzee (1997)
Ryan et a/. (1989j, Ryan & Watkins (1989),
Marshall el a/. (1995a)', Coerzee (1997)
(DJM, pers. 011s.)
(DJM, pcrs. o l x )
Somme (1986)', Sonime el a!. (1993)
Sornme ( 1 986)', Coetzee (1997)
Sornmc (1986)', Coctzee (1997)
Cortzec (1 997)
Coetzee ( I 997)
Dalenius & Wilson (1 958) (see Cortzec, 1997)
Ohyaina & Hiruta ( I 91)5), Coetzer (1 997)
Wallwork (1962), Coetzee (1997), Gressitt
(1965) Gressitt & Shoup (1967)
Coetzee (1 997)
' Marshall e/ al. (I 99523) incorrectly refer to Af. udJoni as hf.pr/ronia.
' In all papers prior t o Coetzee (1997), Af. niarshalli is given as hf. zilsoni.
onset of the Pliocene-Pleistocene glaciation, suggesting that the widespread distribution of i2faudheimia indicates its antiquity to the continent, and at least a prePliocene continental existence.
Ecology: local distribution and abundance
Maudheimia is vertically distributed in Continental Antarctica over a range of
altitudes, from low nunataks (c. 200 m altitude) to the mountain peaks (c. 2000 m)
(Table 2). Antarctic altitudes were much greater prior to the ice sheet development
(Pliocene-Pleistocene),which currently depresses the continental plate. Nunataks are
more likely to be inundated by ice than are the higher mountain peaks. Numerous
factors must influence the occurrence of Maudheimia at nunataks. Its absence from
low altitudinal and high latitudinal nunataks in the Ahlmannryggen (DJM, pers.
observ.) suggest these to include minimum temperature, water availability, and longterm (geological)frequency/extent of potential ice scour events.
In an assessment of within-nunatak abundance variation of 111.wilsoni (determined
at Ice Axe Peak, Robertskollen (7 1"28'S, 3"15'E), Ahlmannryggen, western Dronning
Maud Land), the effects of aspect, height and proximity to a bird colony were
considered (see Ryan et al., 1989 and Ryan & Watkins, 1989, for descriptions of the
habitat and biota at Robertskollen). Density at the summit (250 individuaW0.25 m'
or 1000 individuals/m') was vastly greater than elsewhere on the nunatak (less than
D. J. MARSHALL AND L. COETZEE
122
TABLE
3. Density (individuals per 0.25 m') of Maudheimia wzlsoni at Ice Axe Peak, Robertskollen
Probability (Pvalue)
Mean f 1 SD (n= 20)
20.15f 16.34
250.15+ 180.02
64.65 f94.85
20.95 k48.70
Site 1
Site 2
Site 3
Site 4
~
~~~
Site 2
Site 3
Site 4
0.000
0.113
0.008
0.000
0.005
0.000
~
Sampling was undertaken at four sites (approximately 500 m2 each) of varying orientation, vertical position, and
proximity to bird colony, on the nunatak Ice Axe Peak, Robertskollen (altitude 480 m), Ahlmannryggen, Dronning
Maud Land: site (1) summit above a bird colony, site (2) north east slope within a bird colony, site (3) flat area
below the north east slope, and site (4) west slope within a bird colony. For each site, twenty randomly selected
ice-sorted polygons were sampled. Density was determined hy counting mites under the stones of the polygon
within a 0.25 m2 quadrat. The probability of density being significantly different, at different sites was determined
using a Mann-Whitney U-test.
TABLE
4. Association of Maudheimia wilsoni with three plant species
Usnea anhrctica
Umbilicana decussata
Bryophyte
Pearson's r coefficient
Probability (f-value)
0.4656
0.8301
0.0391
0.000
0.000
0.731
See Table 3 for sampling procedure. Mite density for the 80 quadrats was compared with the cover of the
prominent lichens Umbilicaria decussata, Usnea antarctica and an unidentified hryophyte, in the same quadrats. Cover
was assessed by using a 49 squared grid (approximately 900 cm').
70 individuald0.25 m2 or 280 individuals/m2; Table 3). These data suggest greater
instability of habitat on the slopes, probably due to a greater frequency of ice scour
over geological time, and the poor capacity of Maudheimia for recolonization on the
nunatak. Stability of the summit habitat would also explain the greater cover there
of Umbilicaria decussata, the lichen favoured by Maudheimia (Table 4).
Ecology: adaptationsfor an epilithic existence in continental Antarctica
The nunataks and mountains of Continental Antarctica are characterized by
chalicosystems: habitats of lithosol, gravel or rock (Janetschek, 1963). Specialization
for an epilithic (rock) existence is seen in the morphology, physiology, life history
and feeding of Maudheimia. Although Maudheimia is found in association with the
alga Prasiola crispa (DJM, pers. observ.), it is primarily lichenivorous (Wallwork, 1962;
Dalenius, 1965; Gressitt, 1965; Gressit & Shoup, 1967; Seyd & Seaward, 1984;
Ohyama & Hiruta, 1995). Prasiola grows in ornithogenically-enriched habitat patches
on the nunataks and is a relatively recent Continental Antarctic inhabitant (the
earliest record of bird presence at Antarctic nunataks is c. 35 000 ya; Hiller et al.,
1988). It is probable that prior to this, Maudheimia had an association with epilithic
lichens only, to some extent corroborated by high densities of Maudheimia amongst
lichens (Umbilicaria decussata and Usnea antarctica) as opposed to bryophytes (Table 4).
Little is known about the origins of lichens in Continental Antarctica (Seppelt, 1995),
limiting further support of the Maudheimia-lichen historical association. No other
GONDWANAN ORIGIN FOR hUlJDHEZML4
123
acarine species found in DML is, however, known to live or feed on lichens (DJM,
pers. observ.).
Aspects of the physiology of Muudheimiu support epilithic adaptation. Summer
rock habitat temperature fluctuates diurnally, often reaching upper temperatures of
30°C (Marshall et ul., 1995a). Muudheimiu wilsoni increases physiological rate linearly
with temperature, over the entire range of positive temperatures it experiences
(Marshall et ul., 1995a). Rate is accelerated more rapidly than in sub-Antarctic
oribatid mites, which are not normally exposed to similar high temperatures (Marshall
& Chown, 1995). This presumably maximizes feeding by Muudheimiu during the
short summers characterizing Continental Antarctica (Marshall et ul., 1995a).Muudheimiu also has a higher desiccation tolerance than its sub-Antarctic counterparts,
which are naturally exposed to wetter conditions (Marshall, 1996).Its relatively poor
submergence tolerance argues against a lowland, sub- or maritime Antarctic origin
(Marshall, 1996).
The formation of compact multi-instar aggregations under stones, and the adhesion
of eggs to rock surfaces, are other possible epilithic adaptations of Muudheimiu
(Marshall & Convey, 1999). Long generation times (up to 5 years to mature) and
the low fecundity (two to four large eggs per female lifespan) of Muudheimiu (Marshall
& Convey, 1999) are consistent with an existence in adverse, but stable habitats
(Greenslade, 1983; Convey, 1996), and imply a potentially slow evolutionary rate.
While rapid evolution would be unnecessary in an abiotically stable environment
devoid of parasites, predators, and competitors, benefit is potentially gained from
preserving a genotype suitable for the prevailing Antarctic adversity (Greenslade,
1983; Convey, 1996).
Although the female genital openings of Muudheimia and its Continental Antarctic
counterpart, Anturcticolu mgeri (Sugawara et ul., 1995),are relatively large (presumably
relating to their large eggs), the distinctive characters separating Muudheimiu from
the outgroups show reduction in size or loss of structures (see Results). Small
structures of Maudheimiu putatively relate to an epilithic habitat (as opposed to an
edaphic habitat), which also lacks predators. (The only known predatory mite
occurring in Continental Antarctica is the prostigmatid mite Coccorhugidiu gressitti
Womersley & Strandtmann (see Marshall & Pugh, 1996), and it is not known to
feed on or live in the same regions as Muudheimiu). Thick cuticles and large
integumental structures in oribatid mites are thought to provide protection from the
rigours of soil abrasion and/or predation (Alberti et ul., 1981; Schmid, 1988).
Speciation
Glaciation of Antarctica commenced during the late Eocene (c. 45 mya; Clarke
& Cramme, 1992). Since then the continent has experienced extreme temperature
fluctuations. The most severe glaciation event leading to the formation of the East
Antarctic ice sheet was fairly recent (Pliocene-Pleistocene;Clarke & Cramme, 1992).
Though this event had the greatest effect of obliterating the Antarctic biotas and
isolating populations, temperate valley glaciers could have been prominent during
the earliest of glaciations (Clarke & Cramme, 1992). In any event, the most likely
survivors were the high montane species like Muudheimiu, which escaped ice cover
and were pre-adapted for extremely low temperatures.
Antarctic distributions of the Muudheimiu species strongly support speciation
12.1
D. J MARSHALL AND L COETZEE
resulting from glaciation-induced isolation of populations (Fig. 2). The basal species,
M. petronia, is isolated from the DML species, which are themselves isolated from
each other in a phylogenetic pattern consistent with Pliocene-Pleistocene glaciation
patterns (Fig. 1). If speciation were pre-glacial, numerous other distribution patterns
for the species could have emerged, the most extreme case being a random pattern.
Speciation mediated by glaciation is further supported by the circumferentially
anticlockwise sequence of events producing the four species of Maudheirnia, from
Victoria Land, across East Antarctica to DML. This conforms to a directional
constraint as suggested by a theoretical model for the development of the East
Antarctic ice sheet (Marchant et al., 1993). Warming leads to ice sheet recession,
exposing a rocky corridor along the coastal edge of the continent. The opposite
effect, resulting from cooling, would have isolated populations along this corridor,
as inhabitable space was reduced. Had pre-glacial speciation occurred, the sequences
and directions of speciation would not have been expected to correspond to this
particular pattern across the extent of the continent.
Our data do not permit speculation on previous geographical ranges of the
putative common ancestors of Maudheimia species. Neither can we determine with
any robustness whether the actual process of isolation occurred by peripheral
isolation (sequential or otherwise) or vicariance (Wiley, 1981; Wiley & Mayden,
1985; Funk & Brooks, 1990; Brooks & McLennan, 1991, 1993). It should also be
realized that simultaneous development of isolation barriers (ice sheet development)
separating the DML species in particular, could have effected polychotomous
speciation.
CONCLUSIONS
The antiquity of Maudheimia in continental Antarctica is indicated by its restriction
to the continent, and its widespread distribution across the continent in the light of
a poor capacity for dispersal. The K- or A-selected life history attributes, lichenivory,
temperature-dependent physiology and summit-concentrated local distributions, all
suggest adaptation for a high montane, epilithic existence. This would be essential
for the continued survival of the extreme climatic changes that Antarctica has
undergone. The above support the existence of Maudheimia, prior to the final
separation of Gondwana and the glaciation of Antarctica. The closest relatives of
Maudheimia, therefore, may be expected to occur in mountainous regions of the
other Gondwanan fragments, rather than in the sub/maritime Antarctic regions.
Though the genus appears to have resided in Antarctica for a substantial period of
time, the sequence of speciation events producing the four known extant species of
Maudheimia indicates speciation occurring after the onset of glaciation (late Eocene),
probably during the most recent glaciation event (Pliocene-Pleistocene).
Hoberg (1992, 1995 also Hoberg & Adams, 1992) recently presented phylogenetic
and biogeographical evidence supporting the hypothesis that speciation involving
several invertebrate parasite taxa occurred during the Pliocene-Pleistocene glaciation
period in the Arctic. This scenario, dubbed the Boreal Refugium Hypothesis (see
also Brooks & McLennan, 1993), is remarkably similar to the one we propose herein
to explain evolution in Maudheimia. This study may therefore suggest that similar
evolutionary dynamics, speciation as well as extinction, were operating in both
boreal regions of the planet during the Pliocene-Pleistocene period.
C;OND\VANAN ORIGIN FOR AlAL'DHIiZJIIA
125
Daniel R. Brookes (University of Toronto, Canada), Roy Norton (State University
of New York, U.S.A.), Valerie Behan-Pelletier (Agriculture and Agri-Food Canada,
Canada), Steven L. Chown (University of Pretoria, South Africa), Kevin J. Gastori
(University of Sheffield, U.K.), Philip J.A. Pugh (British Antarctic Survey, U.K.) and
Penelope Greerislade (CSIRO, Australia) are thanked for advice concerning the
phylogenetic analysis and/or critically commenting on earlier versions of this paper.
D.J.M. acknowledges PhilipJ.A. Pugh for stimulating ideas on the topic in an earlier
collaboration. Johaii J. Spies (University of the Orange Free State, South Africa) is
thanked for the use of the PAUP 3.1.1 programme and computer equipment.
Lennart Cederholm (University of Lund, Sweden) and Sabina Swift (Bishop Museum,
Hawaii, U.S.A.) provided the type material of M. rmlilsoni and Ad.petronia, respectively.
Jan E. Crafford helped with the fieldwork at Robertskollen, Antarctica, in 1992/3,
when D.J.M. was under the employment of the FitzPatrick Institute, University of
Cape Town, South Africa. The South African Department of Environmental Affairs
and Tourism provided logistical and financial support through the South African
Committee for Antarctic Research.
REFERENCES
Alberti G, Fernandez NA. 1990. Aspects concerning the structure and function of the leriticulus
and clcar spot of certain oribatids (Acari, Orihatidaj. Ararologia 31: 65-72.
Alberti G, Storch V, Renner H. 1981. Ultrastructure of the cuticle of Acari (Arachnidaj. zoologische
Jnhrburhm Jena 105: 183%236.
Alberti G, Kaiser Th, Fernandez NA. 1991. Fine structure of photorecrptor organs in Acari. In:
Dusbabek F, Bukva V, eds. Modern Acarolop. The Hague: SPB Academic Publishing, 343-348.
Balogh J, Balogh P. 1984. A review of the Oribatuloidea Thor, 1929 (Acari: Oribateij. Arta ~oologii-a
dcadeniicae srientiamrn hungarirae, Budajmt 30: 257-3 13.
Balogh J, Balogh P. 1992. The oribatid mites genera Ofthe world. Budapest: Hungarian National Museum
Press.
Bayly IAE. 1994. GladioJi.rrnsHenry (Copepoda: Calanoida) discovered in Antarctica: G. antarcticus sp.
nov. dcscrihed from a lake in the Bunger Hills. Polut Biology 14: 253-259.
Behan-Pelletier VM. 1984. C'erato&r (Acari: Ceratozetidae) of Canada and Alaska. T h e Cunndian
Entornologid 116: 1449-1517.
Behan-Pelletier VM. 1985. Ceratozetidae of the western North American Arctic. 'The Canadian
Entomologict 117: 1287- 1366.
Behan-Pelletier VM. 1986. Ceratozetidae (Acari: Oribatei) of the western North American Subarctic.
?he Canadian Enfon~okogzst118: 991-1057.
Broady PA. 1996. Diversity, distribution and disprrsal of Antarctic terrestrial algae. Biodiversijy and
Consemation 5: 130771335,
Brooks DR, McLennan DA. 1991. Plyloge?y, EcoloD and Behavior: il Research program in Comparatizu
Biolo,~.Chicago: LJniversity of Chicago Press.
Brooks DR, McLennan DA. 1993. Parnscript: Parasiles and the languqe cf evolution. Washington DC:
Smithsonian Institution Press.
Clarke A, Cramme JA. 1992. The southern ocean henthic fauna and climate: a historical perspective.
Philosophical Transart2on.i of the Royal Society. London B 338: 299-309.
Coetzee L. 1996. A re-evaluation of the Antarctic mite genus ,24audheimin Dalenius & Wilson, 1958
(Acari, Orihatidaj. Unpublished hISc Thesis, University of the Orange Free State, South Africa.
Coetzee L. 1997. The Antarctic mite genus Afaudheimia (Acari, Oribatidaj. ,Vaziorsinge van dir .hhszonale
Alu.wunz, BloenEfbntein 13: 101-134.
Convey P. 1996. The influcnce of environmental characteristics on life history attributes of Antarctic
trrrestrial biota. Biological Reoierc~71: 19 1-225.
126
D. J. MARSHALL AND L. COETZEE
Convey P, Greenslade P, Pugh PJA. 2000. The terrestrial microarthropod fauna of the South
Sandwich Islands. Journal OfNatural History 34: 597-6 10.
Dalenius P. 1965. The acarology of the Antarctic regions. In: Van Oye P, Van Mieghem J, eds.
Biogeograpty and ecology in Antarctica. The Hague: W. Junk, 414-430.
Dalenius P, Wilson 0. 1958. On the soil fauna of the Antarctic and of the sub-Antarctic islands.
The Oribatidae (Acari). Arkiv3r <oologi 11: 393-425.
Ellis-Evans JC, Walton D. 1990. The process of colonization in Antarctic terrestrial and freshwater
ecosystems. Pmceedings ofthe NIPR $mnposium on Polar Biology 3: 151-163.
Evans GO. 1992. Princ$hs ofAcarology. Cambridge: Cambridge University Press.
Frati F, Fanciulli PP, Carapelli A, Dallai R. 1997. The Collembola of northern Victoria Land
(Antarctica): distribution and ecological remarks. Pedobiologia 41: 50-55.
Funk VA, Brookes DR. 1990. Phylogenetic systematics as the basis of comparative biology. Smithsonian
Contributions to Botany 73: 1-45.
Goodwin ID. 1993. Holocene deglaciation, sea-level change, and the emergence of the Windmill
Islands, Budd Coast, Antarctica. Quartemav Researrh 40: 70-80.
Grandjean F. 1934. Les poils des epimkres chez les Oribates (Acariens).Bulletin du hfusium 6: 504-5 12.
Grandjean F. 1935. Les poils et les organes sensitifs port& par les pattes et le palpe chez les oribates.
Bulletin de la Sociiti <oologique de France 60: 6-39.
Grandjean F. 1940. Les poils et les organes sensitifs port& par les pattes et le palpe chez les oribates.
Deuxikme partie. Bulletin de la Soriiti <oologique de France 65: 32-4 1.
Grandjean F. 1949. Formules anales, gastronotiques, genitales et aggenitales du developpement
numtrique des poils chez les Oribates. Bulletin de la Sociiti zoologique de France 74: 201-225.
Grandjean F. 1951. Observations sur les Oribates (23' strie). Bulletin du i2hsbum 23: 261-268.
Grandjean F. 1952. Au sujet de l'ectosquelette du podosoma chez les Oribates Suptrieurs et de sa
terrninologie. Bulletin de la Sociiti <oologique de France 78: 13-36.
Grandjean F. 1953. Essai de classification des Oribates (Acariens). Bulletin de la Sociiti <oologzque de
France 28: 421-446.
Grandjean F. 1963. Concernant Sphaerobates gratus, les Mochlozetidae et les Ceratozetidae (Oribates).
Acarologia 5: 284-305.
Grandjean F. 1970. Nouvelles observations sur les Oribates (8e strie). Acarologia 12: 849-876.
Greenslade PJM. 1983. Adversity selection and habitat template. American Naturalist 122: 352-365.
Greenslade P. 1995. Collembola from the Scotia Arc and Antarctic Peninsula including descriptions
of two new species and notes on biogeography. Polskie Paimo Entomologiczne Bulletin Emtomologique de
Pologne 64: 305-319.
Gressitt JL. 1965. Biogeography and ecology of land Arthropods of Antarctica. In: Van Oye P, van
Mieghem J, eds. Biogeography and ecology in Antarctica. The Hague: WJunk, 431-490.
Gressitt JL, Shoup J. 1967. Ecological notes on free-living mites in North Victoria Land. In: Gressitt
JL, ed. Entoniologv in Antarctica (Antarctic Researrh Series I O), Washington DC: American Geophysical
Union, 307-32 1.
Grobler L. 1993. Species of the genus agoribatula Berlese, 1916 (Acari, Oribatida, Oribatulidae) from
South Africa I. New species. Navorsinge van die Nasionale hfuseum, Bloerrfontein 9: 49-76.
Hiller A, Wand U, Kampf H, Stackebrandt W. 1988. Occupation of the Antarctic continent by
petrels during the past 35 000 yrs: inferences from a "C study of stomach oil deposits. Polar Biology
9: 69-77.
Hoberg EP. 1992. Congruent and synchronic patterns in biogeography and speciation among seabirds,
pinnipeds and cestodes. Journal Of Parasitology 78: 60 1-6 15.
Hoberg EP. 1995. Historical biogeography and modes of speciation across high-latitude seas of the
Holarctic: concepts for host-parasite coevolution among the Phocini (Phocidae)and Tetrabothriidae
(Eucestoda). Canadian Journal o f ~ o o l o g y73: 45-57.
Hoberg EP, Adams AM. 1992. Phylogeny, historical biogeography and ecology of Anophryocephalus
spp. (Tetrabothriidae) among pinnipeds of the Holarctic during the late Tertiary and Pleistocene.
Canadian Journal of ~ o o l o g v70: 703-7 19.
Ingolfsson 0, Hjort C, Berkman PA, Bjorck S, Colhoun E, Goodwin ID, Hall B, Hirakawa
K, Melles My Moller P, Prentice ML. 1998. Antarctic glacial history since the Last Glacial
Maximum: an overview of the record on land. Antarctic Srience 10: 326-344.
Janetschek H. 1963. Arthropod ecology of South Victoria Land. In: Gressitt L, ed. Entomologv in
Antarctica (dntarctic Restarch Series 10). Washington DC: American Geophysical Union, 205-293.
Judson M. 19??. Identity of the Antarctic mite Gainia nizialis Trouessart (Acari, Nanorchestidae).
Bulletin du Afusium national #Histoire naturelle, Paris 17: 83-86.
Marchant DR, Swisher CC, Lux DR, West DP, Denton GH. 1993. Pliocene paleoclimate and
East Antarctic ice-sheet history from surficial ash deposits. Science 260: 667-669.
Marshall DJ. 1996. Comparative water relations of sub-Antarctic and continental Antarctic oribatid
mites. Polar Biologi 16: 287-292.
Marshall DJ, Chown SL. 1995. Temperature effects on locomotor activity of sub-Antarctic oribatid
mites. Polar Biology 15: 47-49.
Marshall DJ, Pugh PJA. 1996. Origin of the inland Acari of continental Antarctica, with particular
referencc to Dronning Maud Land. <oologzralJounial ofthe Linnean Society 118: 101-1 18.
Marshall DJ, Convey P. 1999. Compact aggregation and life history strategy in a continental
Antarctic mite. In: Bruin J, van der Gecst LPS, Sabelis MW, eds. Evolution and Ecologv of Acari.
Dordrccht (The Nethcrlands): Kluwer Academic Publishers, 557-567.
Marshall DJ, Newton IP, Crafford JE. 1995a. Habitat temperature and potential locomotor
activity of the continental Antarctic niitc, hlaudheinzia petroriia Wallwork. Polar Biology 15: 4 1-46.
Marshall DJ, Crafford JE, Krynauw JR, Drummond AE, Newton IP. 1995b. The hiolocgy,
physico-chemistry arid gcology of a nunatak pond at Valterkulten, wcstern Dronning Maud Land,
Antarctica. LS'oiit/i.4jiican Journal of Antarctic Research 25: 9-1 6 .
McInnes SJ, Pugh PJA. 1998. Biogeography oflimno-terrestrial Tardigrada, with particular reference
to the Antarctic fauna. Journal OfBiogeography 25: 31-36.
Menke H-G. 1963. Rcvision der Ceratozctidae, Ceratozete.\ peritus Grandjean (Arach., Acari, Orihatei).
Senrkenbergiann biologi(.a 44: 14 1 154.
Menke H-G. 1964. Revision der Ceratozetidae, 2. C'erato~etesgracilis(Michael) (Arach., Acari, Oribatei).
tS'enckenbergiann biologim 45: 62 1-634.
Myers AA, Giller PS. 1988. ,-lna(stical biogeography. An integrated approach to the Jtudy o f aninial and plant
distributions. London: Chapman and Hall.
Norton RA. 1977. A review of F. Grandjean's system of leg chactotaxy in the Orihatei and its
application to the Damaeidae. In: Dindal DL, ed. Biology of oribatid mites. New York: State University
of New York, 33-62.
Norton RA, Behan-Pelletier VM. 1986. Systematic relationships of Propelops, with a modification
offamily-group tasa in Pheiiopelopoidea (Acari: Oribatida). CariadianJournal of<oology 64: 2370-2383.
Norton RA, Alberti G, Weigmann G, Woas S. 1997. Porose integumental organs of oribatid mites
(Acari, Oribatida) 1. Overview of types and distribution. <oologim 48: 1-31.
Ohyama Y, Hiruta S-i. 1995. The terrestrial arthropods of Sor-Rondane in castern Dronning Maud
Land, Antarctica. with biogcographical notcs. Polar Biology 15: 34 1--347.
Pugh PJA. 1993. A synonymic cataloguc of the Acari from Antarctica, the sub-Antarctic islands and
the Southcrn Ocean. Jounial of.Vatura1 Hi.\tory 27: 323-42 1.
Pugh PJA, King PE, Fordy MR. 1987. A comparison of the structure and function of thc
cerotegument in two species of Cryptostigmata (Acarina). Jounial Of.hGatural History 21: 603-6 16.
Ryan PG, Watkins BP. 1989. The influence of physical factors and ornithogcnic products on plant
and arthropod abundancc at an inland nunatak group in Antarctica. Polar Biology 10: 151-160.
Ryan PG, Watkins BP, Lewis Smith RI, Dastych H, Eicker A, Foissner W, Thompson G.
1989. Biological sur\.ey of Rohertskollen, wcstern Dronning Maud Land: area dcscription and
prcliminary species lists. South African Joirn~alofAn/arc&- Research 19: 10-20.
Schmid R. 1988. Morphological adaptations in a predator-prey-system: Scydmaenidae and armoured
mites. <oologishe Jahr-bii(-hel:3ena 115: 207--228.
Seniczak S, Behan-Pelletier VM, Solhey T. 1990. Systematic value of losses of some notogastral
setac in adult Sphacrozetinae (Acari: Orihatida: Ceratozctidae) in the light of ontogcnetic studies.
Bcarologia 31: 385-400.
Seppelt RD. 1995. Phytogcography of continental Antarctic lichens. Lzrhenologist 27: 41 7-43 1.
Seyd EL, Seaward MRD. 1984. The association of orihatid mitcs with lichens. <oologzcal Journal OJ
the LinnPan 5orietv 80: 369-420.
Semme L. 1986. New records of terrestrial arthropods fkom Dronning Maud Land, Antarctica. Polar
Re.search 4: 225-229.
Semme L, Stremme A, Zachariassen KE. 1993. Notcs on the ecolo'gy and physiology of the
Antarctic orihatid mitc A21audheiniia u~il.mi.Polar Research 12: 2 1-25.
S t m J, Block W. 1995. Orihatid mites (Acari: Oribatida) of South Georgia, South Atlantic. Jounial
ofNatural Hisfop 29: 1469- 148 1.
Sugawara H, Ohyama Y, Higashi S. 1995. Distribution and temperaturc tolerances of the Antarctic
free-living mite dntclrc.ticola mpyeri (Acari, Cryptostigmata). Polar Biologv 15: 1-8.
-
I28
D. J. MARSHALL AND L. C O E l Z E E
Swofford DL. 1993. PAUP: Phylogenetic anabsis usingparsimoy, version 3.1.1.Washington DC: Smithsonian
Institution Press.
Travk J, Andre HM, Taberly G, Bernini F. 1996. L.es acariens Oribates. Wavre: AGAR.
Wallwork JA. 1962. hfaudheimia petronia n.sp. (Acari: Oribatei), an oribatid mite from Antarctica.
Pat@ Insects 4: 865-868.
Wallwork JA. 1966. More oribatid mites (Acari: Cryptostigmata) from Campbell I. Pacijc Insects 8:
849-87 7.
Wallwork JA. 1967. Cryptostigmata (oribatid mites). In: GressittJL, ed. Entomologv in Antarctica (Antarctic
Research Series lo), Washington DC: American Geophysical Union, 105-1 22.
Wallwork JA. 1973. Zoogeography of some terrestrial micro-arthropoda in Antarctica. Biological
Reviews 48: 233-259.
Walton DWH. 1990. Colonization of terrestrial habitats organisms, opportunities and occurrence.
In: Kerry KR, Hempel G, eds. Antarctic ecosystems. Ecological change and conservation. Berlin: Springer,
5 1-60.
Wiley EO. 1981. Phylogenetics: the theoy andpractice ofphylagenetic systematicJ. New York Wiley-Interscience.
Wiley EO, Mayden RL. 1985. Species and speciation in phylogenetic systematics with examples
from the North American fish fauna. Annals of the Missouri Botanicat Gardens 72: 596-635.
Wise KAJ, Gressitt JL. 1965. Far southern animals and plants. Nature 207: 101-102.
Woodring JP. 1962. Oribatid (Acari) Pteromorphs, Pterogasterine phylogeny and evolution of wings.
Annales ofthe Entomological Socieg of America 55: 394-403.
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