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Chin shield configuration in Gehyra treated here; A) G. kimberleyi WAMR175035, B) G. pilbara WAMR108632, C) G. girlooloo sp. nov. WAMR175045 and D) G. nana WAMR175063. Scale bar = 1 mm.
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Ongoing fieldwork and molecular research continues to reveal that the monsoonal tropics of northern Australia contain more vertebrate species than currently recognised. Here we focus on two morphologically distinctive, yet unrecognised forms in the genus Gehyra from the southern Kimberley region and surrounding deserts. We base our descriptions on...
Contexts in source publication
Context 1
... Gehyra pilbara (with which it has frequently been confused) it can be distinguished by its larger size (max SVL 62.3 versus 45.1 mm), tall, narrow postmentals (versus extremely short and wide; cf. Fig. 4), and tan or greyish-brown dorsal colouration (vs. ...
Context 2
... further species in this group, G. pilbara, is similarly small, but differs in dorsal colouration (reddish-brown vs. pinkish-grey), the presence of obviously enlarged loreal scales above the infralabials (versus absent) and in having an extremely short snout resulting in short, wide postmentals (versus tall and thin in G. girloorloo sp. nov.) (Fig 4.). ...
Citations
... Gehyra calcitectus sp. nov. is the fourth recently described or redescribed lizard species with a restricted range in the limestone ranges along the southern and eastern fringes of the Kimberley (Oliver et al., , 2016aDoughty, Ellis & Oliver, 2016). Additional limestone endemics lineages from the southern and eastern Kimberley, and the Victoria Rivers District district are likely to represent additional undescribed species (C. ...
For over two decades, assessments of geographic variation in mtDNA and small numbers of nuclear loci have revealed morphologically similar, but genetically divergent, intraspecific lineages in lizards from around the world. Subsequent morphological analyses often find subtle corresponding diagnostic characters to support the distinctiveness of lineages, but occasionally do not. In recent years it has become increasingly possible to survey geographic variation by sequencing thousands of loci, enabling more rigorous assessment of species boundaries across morphologically similar lineages. Here we take this approach, adding new, geographically extensive SNP data to existing mtDNA and exon capture datasets for the Gehyra australis and G. koira species complexes of gecko from northern Australia. The combination of exon-based phylogenetics with dense spatial sampling of mitochondrial DNA sequencing, SNP-based tests for introgression at lineage boundaries and newly-collected morphological evidence supports the recognition of nine species, six of which are newly described here. Detection of discrete genetic clusters using new SNP data was especially convincing where candidate taxa were continuously sampled across their distributions up to and across geographic boundaries with analyses revealing no admixture. Some species defined herein appear to be truly cryptic, showing little, if any, diagnostic morphological variation. As these SNP-based approaches are progressively applied, and with all due conservatism, we can expect to see a substantial improvement in our ability to delineate and name cryptic species, especially in taxa for which previous approaches have struggled to resolve taxonomic boundaries.
... The genus has long been recognised as taxonomically difficult (King 1979(King , 1983. Recent phylogeographic studies have revealed extraordinary levels of undescribed cryptic diversity within many nominal species of Australian Gehyra (Sistrom et al. 2013;Moritz et al. 2018;Ashman et al. 2018;Noble et al. 2018;Oliver et al. 2019), and more than 20 new species have been described or elevated from synonymy in the last decade (Sistrom et al. 2009;Doughty et al. 2012Doughty et al. , 2018aDoughty et al. , 2018bHutchinson et al. 2014;Oliver et al. 2016;Bourke et al. 2017;Kealley et al. 2018). As a result of these considerable efforts there are now 42 species of Gehyra recognised in Australia, making it the most speciose genus of gekkotan lizards in Australia, with the rocky Pilbara and Kimberley regions of north-western Australia being centres of diversity and endemism (Ashman et al. 2018;Doughty et al. 2018aDoughty et al. , 2018bKealley et al. 2018). ...
... We recommend the common name 'Amber rock dtella' for this species. Recent taxonomic revisions of Gehyra have moved away from recommending 'dtella' in common names, instead favouring 'Gehyra' (Doughty 2018a;Kealley 2018) or simply 'gecko' (Oliver et al. 2016;Doughty 2018b). Kealley et al. (2018) provide justification for this: "We prefer to use 'Gehyra' as the common name over 'dtella' as the generic name is already available and just as easy or difficult to remember than an additional name fabricated for use as a common name." ...
... nov. is intermediate in size between its two sympatric congeners, G. dubia (larger generalist) and G. einasleighensis (smaller rubble specialist). This is similar to the size and habitat divergence seen between other sympatric Gehyra, such as G. kimberleyi Börner & Schüttler, 1983 (larger generalist), G. girloorloo Oliver, Bourke, Pratt, Doughty & Moritz, 2016 (smaller rock specialist), and G. nana Storr, 1978 (tiny rubble specialists) in the south-western Kimberley region (Oliver et al. 2016;Moritz et al. 2018). This offers further observational evidence that sympatric Gehyra typically differ in body size; however, it is still unclear whether sympatry drives body size divergence, whether those species that have already diverged are more likely to coexist upon secondary contact, or if a combination of these two factors contribute to patterns of body size divergence among Gehyra. ...
We describe a new species of rock-dwelling Gehyra Gray, 1834 (Gekkonidae) from the Einasleigh Uplands of inland north Queensland, Australia. Morphological, ecological, and molecular data clearly support the new species as distinct and place it within the 'australis group'. Gehyra electrum sp. nov. is distinguished from congeners by a combination of medium adult size (SVL 46-50 mm), an orange-brown to pinkish-orange background colouration with a pattern of distinct whitish spots and irregular black to purple-brown blotches or bars, possessing 7-8 undivided subdigital lamellae on the expanded portion of the fourth toe, and a wedge-shaped mental scale that separates the inner-postmental scales along 40% or more of their length. Gehyra electrum sp. nov. is a rock specialist currently known only from granite outcrops of the Mt Surprise region, Queensland. This is the second recently described Gehyra from the Einasleigh Uplands and adds to the growing number of endemic reptiles recognised in the region.
... This north-south pattern of species diversity, which appears across multiple groups, has been attributed to an aridity gradient, climate stability or instability, and historical refugia in mesic areas (Afonso Silva et al., 2017;Laver et al., 2018;Palmer et al., 2013). The hypothesis that the presence of rocky refugia drives patterns of diversity is supported by higher diversity along the barrier ranges in the southern Kimberley (Doughty et al., 2018;Oliver et al., 2014Oliver et al., , 2016. ...
... nov.) and one small (D. bennettii), and a smaller generalist woodland species (D. albilabris). Similar body size divergence in sympatric rock-dwelling Gehyra species has been documented in the Kimberley (Moritz et al., 2018;Oliver et al., 2016). In the D. bilineata species group, there is a generalist woodland species (D. margaretae) with smaller body size in the northern Kimberley and a gracile species found in grasslands on river floodplains in the southern Kimberley (D. gracilis sp. ...
... Chromosome evidence from the 1970s and 1980s (King, 1979;Moritz, 1986) indicated several cryptic forms, some of which were described as new species. Beginning with the study of Sistrom et al. (2009), molecular data have unearthed a wealth of phylogenetic diversity in the arid group, while studies in parallel on northern species have also contributed to Gehyra diversity in Australia (Doughty et al., 2012Oliver et al., 2016;Bourke et al., 2017;Moritz et al., 2018). Further studies of Sistrom and colleagues Sistrom, Donnellan & Hutchinson, 2013;Hutchinson et al., 2014) began to clarify the distribution of true G. variegata (Duméril & Bibron, 1836) (type location = Shark Bay in Western Australia (WA)), along with many other cryptic forms, several occurring in the western arid zone and coastal regions. ...
... We tended to not presume species identifications were correct, as the aim was to resolve a cryptic species complex, therefore making prior identifications suspect. We also drew from misidentified specimens that were the focus of other projects (Hutchinson et al., 2014;Oliver et al., 2016). The goal of widespread DNA sequencing was to determine the distribution of species, and to identify putative specimens upon which morphological analysis could be carried out. ...
The methods used to detect and describe morphologically cryptic species have advanced in recent years, owing to the integrative nature of molecular and morphological techniques required to elucidate them. Here we integrate recent phylogenomic work that sequenced many genes but few individuals, with new data from mtDNA and morphology from hundreds of gecko specimens of the Gehyra variegata group from the Australian arid zone. To better understand morphological and geographical boundaries among cryptic forms, we generated new sequences from 656 Gehyra individuals, largely assigned to G. variegata group members over a wide area in Western Australia, with especially dense sampling in the Pilbara region, and combined them with 566 Gehyra sequences from GenBank, resulting in a dataset of 1,222 specimens. Results indicated the existence of several cryptic species, from new species with diagnostic morphological characters, to cases when there were no useful characters to discriminate among genetically distinctive species. In addition, the cryptic species often showed counter-intuitive distributions, including broad sympatry among some forms and short range endemism in other cases. Two new species were on long branches in the phylogram and restricted to the northern Pilbara region: most records of the moderately sized G. incognita sp. nov. are near the coast with isolated inland records, whereas the small-bodied saxicoline G. unguiculata sp. nov. is only known from a small area in the extreme north of the Pilbara. Three new species were on shorter branches in the phylogram and allied to G. montium . The moderately sized G. crypta sp. nov. occurs in the western and southern Pilbara and extends south through the Murchison region; this species was distinctive genetically, but with wide overlap of characters with its sister species, G. montium . Accordingly, we provide a table of diagnostic nucleotides for this species as well as for all other species treated here. Two small-bodied species occur in isolated coastal regions: G. capensis sp. nov. is restricted to the North West Cape and G. ocellata sp. nov. occurs on Barrow Island and other neighbouring islands. The latter species showed evidence of introgression with the mtDNA of G. crypta sp. nov., possibly due to recent connectivity with the mainland owing to fluctuating sea levels. However, G. ocellata sp. nov. was more closely related to G. capensis sp. nov. in the phylogenomic data and in morphology. Our study illustrates the benefits of combining phylogenomic data with extensive screens of mtDNA to identify large numbers of individuals to the correct cryptic species. This approach was able to provide sufficient samples with which to assess morphological variation. Furthermore, determination of geographic distributions of the new cryptic species should greatly assist with identification in the field, demonstrating the utility of sampling large numbers of specimens across wide areas.
... As it happens the trail of published literature alone supports the taxonomy and nomenclature herein and so I cite it all here. The important published material relevant to the taxonomy and nomenclature of Gehyra sensu lato as defined herein and the decisions made herein are as follows: Andersson (1913), Barbour (1912), Bauer (1994), Bauer and Günther (1991), Beckon (1992), Bobrov and Semenov (2008), Boettger (1895), Bonetti (2002), Schüttler (1982, 1983), Boulenger (1883Boulenger ( , 1885aBoulenger ( , 1885bBoulenger ( , 1887, Brongersma (1930Brongersma ( , 1948, Brown (2014), Brown (1955, Brown et al. (2015), Bourke et al. (2017), Buden and Taboroši (2016), Chan-ard et al. (1999Chan-ard et al. ( , 2015, Chrapliwy et al. (1961), Cogger (2014, Cogger et al. (1983), Crombie and Pregill (1999), Daan and Hillenius (1966), Davies (2012), de Rooij (1915, de Vis (1890), Doody et al. (2015), Doughty et al. (2012), Duméril and Bibron (1836), Duméril and Duméril (1851), Ezaz et al. (2009), Fallend (2007), Fisher (1997), Fitzinger (1843, Flecks et al. (2012), Fry (1914, Garman (1901), Gibbons and Clunie (1984), Girard (1858), Glauert (1955), Goldberg (2014), Gray (1834Gray ( , 1842aGray ( , 1842bGray ( , 1845, Grismer et al. (2007), Günther (1877), Hagey et al. (2017), Hall (2002, Hediger (1933), Heinicke et al. (2011), Horner (2005), Hoser (1989, Hutchinson et al. (2014), King (1979King ( , 1982aKing ( , 1982bKing ( , 1984aKing ( , 1984b, King and Horner (1989), Kinghorn (1924), Kluge (1982Kluge ( , 1993, Kopstein (1926), Laube and Langner (2007), Lesson (1830), Loveridge (1934Loveridge ( , 1948, Low (1979), Lucky and Sarnat (2010), Macleay (1877), Manthey and Grossmann (2007), Maryan (2009), McCoy (2015, Mertens (1974), Meyer (1874), Moritz et al. (2017), Oliver et al. (2010, 2012, 2016a, 2016b, 2017, Mitchell (1965), Oudemans (1894), Peters (1874Peters ( , 1875, Peters and Doria (1878), Pianka (1969), Pianka and Pianka (1976), Ride et al. (1999), Rocha et al. (2009), Rösler (2000, 2017, Rösler et al. (2005), Sang et al. (2009), Shea and Sadlier (1999), Sistrom et al. (2009Sistrom et al. ( , 2012Sistrom et al. ( , 2013, Skipwith and Oliver (2014), Strauch (1887), Steindachner (1867), Sternfeld (1925), Storr (1978Storr ( , 1982, Taylor (1962Taylor ( , 1963, Tiedemann et al. (1994), Tonione et al. (2016), Underwood (1954), Wiegmann (1834), Wellington (1984, 1985), Werner (1901), Wilson and Knowles (1988), Wilson and Swan (2017), Yamashiro and Ota (2005), Zug (1991Zug ( , 2013, Zug and Kaiser (2014), Zug et al. (2011Zug et al. ( , 2012 and sources cited therein. In terms of the nomenclature herein, no names should be altered in any way unless absolutely mandatory under the rules of the International Code of Zoological Nomenclature (Ride et al. 1999). ...
ABSTRACT
The lizard genus Gehyra Gray, 1834 as currently recognized consists of roughly 50 recognized species found
naturally occurring from mainland south-east Asia to Australia and nearby islands to the north and east
including the mid Pacific.
This number of currently unrecognized species probably exceeds already described species-level taxa, even
though this paper formally names 9 new species and 2 new subspecies, all bar one of which have been
confirmed by published molecular data.
In spite of the ancient heritage of the assemblage, which is unusual in that numerous species occur on both
the Asian and Australian continental plates, divergent lineages with antiquity measured potentially in excess
of 25 MYA continue to be treated as being within a single genus.
To correct the anomaly, this paper recognizes major divergent species groups as self-contained genera using
available and newly created genus names in accordance with the International Code of Zoological
Nomenclature (Ride et al. 1999).
The assemblage of Gehyra as recognized by most authors to date is herein divided into 14 genera, ten of
which are formally named for the first time. The species remaining within Gehyra are further divided into two
subgenera, one of which is formally named for the first time. The species within Dactyloperus Fitzinger, 1843
are divided into five subgenera, four of which are formally named for the first time.
Another of the newly named genera Edaxcolotes gen. nov. is also divided into two subgenera.
All newly named genera and subgenera have divergences of more than 10 MYA from all other species based
on numerous published phylogenetic studies.
Keywords: Taxonomy; Nomenclature; Lizard; Gekkota; Gekkonidae; Gecko; Dtella; Gehyra; Perodactylus;
Peropus; Phryia; Phreodora; Dactyloperus; Asia; Australia; New Guinea; Cambodia; Thailand; new genus;
Propemaculosacolotes; Crocodilivoltuscolotes; Edaxcolotes; Extensusdigituscolotes; Brevicaudacolotes;
Parvomentumparmacolotes; Papuacolotes; Quattuorunguiscolotes; Colotesmaculosadorsum; Thaigehyra;
New subgenus; Halmaherasaurus; Purpuracolotes; Maculocolotes; Wedgedigitcolotes; Saxacolinecolotes;
Macrocephalacolotes; species; lacerata, membranacruralis; xenopus; serraticauda; brevipalmata; fehlmanni;
oceanica; australis; occidentalis; pilbara; new species; hangayi; paulhorneri; bradmaryani; sadlieri;
glennsheai; shireenhoserae; marleneswileae; federicorossignolii; grismeri; new subspecies; bulliardi;
graemecampbelli.
... Substantial unrecognised diversity has also been revealed for trees [24], land snails [25], fish [26], frogs [27], and marsupials [28,29]. Meta-analyses of high resolution, comparative phylogeographic diversity across taxa with low dispersal have also revealed new hotspots of endemism that are important to recognise for conservation [30][31][32]. Unrecognised diversity is likely to be especially pronounced for insects in the AMT given that they are so diverse and generally under-studied taxonomically. However, this remains to be investigated. ...
The Australian monsoonal tropics (AMT) is a significant biodiversity hotspot, and recent genetic studies of several vertebrate groups have revealed its level of diversity is far higher than previously thought. However, the extent to which this applies to the AMT’s insect fauna, which represents most AMT faunal species, remains unknown. Here we examine the extent of unrecognised diversity in the AMT’s ecologically dominant insect group, ants. We used CO1 barcoding in combination with morphological variation and geographic distribution to explore diversity within seven taxa currently recognised as single species occurring throughout the AMT: one species of Papyrius Shattuck 1992, one of Iridomyrmex Mayr 1862, two from the Cardiocondyla nuda (Mayr 1866) group, and three from the Camponotus novaehollandiae (Mayr 1870) group. We found six of the seven target species each to represent several species, based on a combination of CO1 divergence (ranging up to 13%), morphological differentiation and geographic distribution. Our findings indicate that the levels of diversity and endemism of the AMT ant fauna are far higher than currently realised. We urge the need for further research in insect biodiversity in the AMT, both for a better understanding of the evolution of its remarkable biota, and as a basis for improved conservation planning.
... King (1979, p. 376) Geckos of the genus Gehyra are among the most taxonomically confusing within the Australian herpetofauna owing to their conservative body form, widely varying characters within taxa, remote locations for many species complexes and poor preservation of colour patterns in museum specimens Sistrom et al. 2009Sistrom et al. , 2014Doughty et al. 2012Doughty et al. , 2018Kealley et al. 2018). Recently, progress has been made resolving the affinities of Gehyra to other gekkonine geckos (Heineke et al. 2011;Gamble et al. 2012;Sistrom et al. 2014) and delimiting species boundaries (Horner 2005;Sistrom et al. 2009Sistrom et al. , 2013Oliver et al. 2010Oliver et al. , 2016Doughty et al. 2012Doughty et al. , 2018Hutchinson et al. 2014). As pointed out 35 years ago, taxonomic progress on Gehyra has been particularly hindered by the loss of colour patterns in preservative and that 'too few specimens from too few localities have been examined' (p. ...
... After this active period in Gehyra systematics, no further species were recognised for over 20 years until the description of G. koira Horner, 2005 (with two subspecies, koira and ipsa) based on morphology. Recent work drawing from combined genetic and morphological data has resulted in many new species descriptions from the Australian Monsoonal Tropics (Doughty et al. 2012Oliver et al. 2016;Bourke et al. 2017) and Central Ranges , and the first proper descriptions of G. lazelli Wells & Wellington, 1983(Sistrom et al. 2009) and G. kimberleyi Börner & Schüttler, 1983. ...
... This integrative approach taken here and elsewhere recently (e.g. Sistrom et al. 2009;Doughty et al. 2012Doughty et al. , 2018Hutchinson et al. 2014;Oliver et al. 2016;Kealley et al. 2018) has proved highly effective at resolving cryptic diversity in conservative Gehyra lineages. ...
... It may also reflect the propensity of geckos to have narrow ranges, tropical distribution and nocturnal behaviour (Gamble, Greenbaum, Jackman, & Bauer, 2015;Meiri, 2016;Vidan et al., 2017). Indeed, the propensity of geckos to specialize in using specific and naturally isolated substrates (usually rocks; e.g., Giri, Bauer, Vyas, & Patil, 2009;Grismer, 2010;Heinicke, Jackman, & Bauer, 2017;Oliver, Bourke, Pratt, Doughty, & Moritz, 2016;Pauwels & Sumontha, 2014;Wood et al., 2017) and speciate where these are found may often predispose them to have very small ranges. Large, relatively continuous patches of habitat, such as Amazonia and the Sahara, on the other hand, harbour many lizard species , but relatively few TL-species ( Figure 1). ...
Aim: Small geographic ranges make species especially prone to extinction from anthropogenic disturbances or natural stochastic events. We assemble and analyse a comprehensive dataset of all the world's lizard species and identify the species with the smallest ranges—those known only from their type localities. We compare them to wide-ranging species to infer whether specific geographic regions or biological traits predispose species to have small ranges.
Location: Global.
Methods: We extensively surveyed museum collections, the primary literature and our own field records to identify all the species of lizards with a maximum linear geographic extent of <10 km. We compared their biogeography, key biological traits and threat status to those of all other lizards.
Results: One in seven lizards (927 of the 6,568 currently recognized species) are known only from their type localities. These include 213 species known only from a single specimen. Compared to more wide-ranging taxa, they mostly inhabit relatively inaccessible regions at lower, mostly tropical, latitudes. Surprisingly, we found that burrowing lifestyle is a relatively unimportant driver of small range size. Geckos are especially prone to having tiny ranges, and skinks dominate lists of such species not seen for over 50 years, as well as of species known only from their holotype. Two-thirds of these species have no IUCN assessments, and at least 20 are extinct.
Main conclusions: Fourteen per cent of lizard diversity is restricted to a single location, often in inaccessible regions. These species are elusive, usually poorly known and little studied. Many face severe extinction risk, but current knowledge is inadequate to properly assess this for all of them. We recommend that such species become the focus of taxonomic, ecological and survey efforts.
... Large areas of exposed limestone karst in tropical regions present spectacular landscapes, and are home to unique, endemic and putatively specialized local biotas in Madagascar [1], Southeast Asia [2] and Australia [3,4]. Lizards often show a particularly close association with karst landforms, including numerous taxa that have only been described recently [5][6][7][8][9][10]. Two broad, and by no means mutually exclusive, hypotheses can be advanced to explain 2017 The Authors. ...
Exposed limestone karst landscapes, especially in the tropics, are often home to distinctive and specialized biotas. Among vertebrates, a particularly large number of karst-associated lizard taxa have been described, but for the vast majority, evidence of specific adaptions to karst is lacking. A number of studies, however, have provided evidence of consistent morphological trends in lizards that use complex, threedimensional, saxicoline habitats such as those that typify karst areas. Here we combine morphological and genetic data to test whether a newly discovered gecko from an extremely rugged karst area in New Guinea shows morphological trends matching those observed in other lizards associated with complex rock habitats such as karst and caves. Consistent with predictions, the new species’ head is flatter and narrower than similar-sized relatives, and it has proportionally larger eyes and longer limbs. These trends indicate this taxon represents the second documented instance of karst specialization in a New Guinean vertebrate, and suggest morphological traits to test for evidence of specialized ecological associations in the many karst-associated Cyrtodactylus taxa from Southeast Asia.
... Geckos in the genus Gehyra are a possible exception in that multiple rock-dwelling species occur in sympatry, especially in the species-rich Kimberley region of north-west Australia (Wilson and Swan 2013). Here, G. nana and its close relatives, G. girloorloo, G. kimberleyi, G. multiporosa, and G. occidentalis (Doughty et al. 2012b;Oliver et al. 2016), occur in various combinations across the complex topography of the mainland and islands (Pepper and Keogh 2014). The broader range of G. nana (to the Top End; Northern Territory) spans several known biogeographic barriers (Eldridge et al. 2011). ...
... These results serve to emphasize the rich and highly endemic diversity of the Australian Monsoonal Tropics (AMT) region, including discovery of previously overlooked hotspots of endemism Oliver et al. 2017). Even with recent taxonomic attention to this complex (Doughty et al. 2012b;Oliver et al. 2016;Bourke et al. 2017), it is clear that further taxa remain to be described. ...
... By contrast, areas in the east of the range (i.e., Top End and Victoria River District; Fig. 1B) mostly have only one nana group taxon present. That phyloendemism for the nana group is concentrated in the north-west Kimberley accords with accumulating evidence of high and unique diversity across this region (Doughty 2011;Doughty et al. 2012a;Oliver et al. 2014a;2014b;Ellis 2016;Moritz et al. 2016;Oliver et al. 2016;Afonso Silva et al. 2017b;Oliver et al. 2017;Laver et al. 2017). ...
Understanding the joint evolutionary and ecological underpinnings of sympatry among close relatives remains a key challenge in biology. This problem can be addressed through joint phylogenomic and phenotypic analysis of complexes of closely related lineages within, and across, species and hence representing the speciation continuum. For a complex of tropical geckos from northern Australia – Gehyra nana and close relatives – we combine mtDNA phylogeography, exon-capture sequencing and morphological data to resolve independently evolving lineages and infer their divergence history and patterns of morphological evolution. Gehyra nana is found to include nine divergent lineages and is paraphyletic with four other species from the Kimberley region of north-west Australia. Across these 13 taxa, 12 of which are restricted to rocky habitats, several lineages overlap geographically, including on the diverse Kimberley islands. Morphological evolution is dominated by body size shifts, and both body -size and -shape have evolved gradually across the group. However, larger body size shifts are observed among overlapping taxa than among closely related parapatric lineages of G. nana, and sympatric lineages are more divergent than expected at random. Whether elevated body size differences among sympatric lineages are due to ecological sorting or character displacement remains to be determined. This article is protected by copyright. All rights reserved
