Vicars in the desert: Substrate specialisation and paleo-erosion underpin cryptic speciation in an Australian arid-zone lizard lineage (Diplodactylidae: Diplodactylus) Author McDonald, Peter J. 0000-0001-6875-1466 Flora and Fauna Division, Northern Territory Department of Environment, Parks and Water Security, Arid Zone Research Institute, south Stuart Highway, Alice Springs, NT, 0870 Australia Author Fenner, Aaron L. 0000-0002-6952-9426 College of Science and Engineering, Flinders University, Biological Sciences, Sturt Rd, Bedford Park, Adelaide, South Australia, 5042 Author Torkkola, Janne 0000-0001-6587-4655 Centre for Planetary Health and Food Security, Griffith University, 170 Kessels Rd, Brisbane, Queensland 4121, and Biodiversity and Geosciences Program, Queensland Museum, South Brisbane, Queensland, 4101 Australia Author Oliver, Paul M. 0000-0003-4291-257X Centre for Planetary Health and Food Security, Griffith University, 170 Kessels Rd, Brisbane, Queensland 4121, and Biodiversity and Geosciences Program, Queensland Museum, South Brisbane, Queensland, 4101 Australia text Vertebrate Zoology 2024 2024-10-03 74 577 594 journal article 10.3897/vz.74.e128775 579E62D6-8A18-4E2D-9F6E-AC0642B48FB3 Genus Diplodactylus Gray, 1832 Type species. Diplodactylus vittatus Gray, 1832 . A genus of Diplodactylidae (sensu Han et al. 2004 ) characterised by robust habitus, wide scansors, numerous (typically> 5) cloacal spurs, two pairs of cloacal bones and an anteriorly enlarged jugal bone entering floor of lacrimal foramen ( Oliver et al. 2007 ). Diagnosis of the Diplodactylus galeatus species complex. All three species in the D. galeatus complex can be differentiated from all other Diplodactylus by the following combination of characters: medium size (to 56 mm ); robust build and relatively short (44–60 % of SVL ) thick tail with regular annuli of slightly enlarged tubercles separated by rows of smaller scales; enlarged dorsal scales up to twice diameter of ventral scales; snout rounded in profile; supralabials and infralabials much larger than bordering loreals; rostral scale in contact with nostril; expanded apical lamellae on all digits; top of head pale yellowish-brown and bordered posteriorly by a rounded dark line; dorsum of body pinkish red to dark red with three to eight dark-edged pale yellowish-brown blotches; and ventral surface uniform white without any pattern. Species in D. galeatus complex specifically differ from other Australian Diplodactylus as follows: from D. ameyi , D. barraganae , D. bilybara , D. calcicolus , D. capensis , D. conspicillatus , D. custos , D. fuller , D. furcosus , D. galaxias , D. granariensis , D. hillii , D. kenneallyi , D. laevis , D. lateroides , D. mitchelli , D. nebulosus , D. ornatus , D. platyurus , D. polyophthalmus , D. savage , D. tessellatus , D. vittatus , and D. wiru by the presence of a series of pale yellowish-brown, dark-edged dorsal blotches on the body and tail; from the eight species in the D. conspicillatus complex ( D. ameyi , D. barraganae , D. bilybara , D. conspicillatus , D. custos , D. hillii , D. laevis , and D. platyurus ) by the presence of enlarged supralabials (versus absent) and terminal lamellae on fingers noticeably wider than digit (versus not wider); from D. galaxias , D. kenneallyi , D. pulcher , and D. savagei in having rostral scale in contact with nostril (versus nostril separated from rostral by small scale); from D. calcicolus , D. capensis , D. furcosus , D. granariensis , D. nebulosus , D. vittatus and D. wiru by the supra and infralabial scales being wider than tall (versus approximately square); from D. lateroides and D. polyophthalmus by the presence of dark edges to the dorsal blotches; and from D. mitchelli and D. ornatus by the absence of a continuous vertebral stripe (rarely present in the D. galeatus species complex).