Gekkonidae

Sistrom, Mark J., Hutchinson, Mark N., Hutchinson, Rhonda G. & Donnellan, Stephen C., 2009, Molecular phylogeny of Australian Gehyra (Squamata: Gekkonidae) and taxonomic revision of Gehyra variegata in south-eastern Australia, Zootaxa 2277, pp. 14-32 : 22-27

Gekkonidae

Dactyloperus lazelli Wells & Wellington, 1985 : p. 11. Holotype: AMS R116972 (formerly AMS Field Series 16793), adult male, from “Mt Colley”, Cocoparra National Park, near Griffith, N.S.W. ( Fig. 5 a).

Dactyloperus annettae Wells & Wellington, 1985 : p. 11. Holotype: AMS R116971 (formerly AMS Field Series 16789), adult female, from Willandra National Park, near Hillston, N.S.W. ( Fig. 5 b).

Diagnosis. A moderate sized Gehyra (max. Snout-vent length (SVL) 59 mm) with divided subdigital lamellae, two or three pairs of enlarged chin shields, a dorsal pattern combining small pale spots and irregular, dark spots or short wavy lines, and a diploid chromosome number of 44. Most similar to G. nana , from which it differs in grey to brown rather than rufous dorsal colouring with more prominent black flecks and lines. Gehyra lazelli is sympatric or parapatric with two other species, G. variegata (2n=40a form) and G. purpurascens . Distinguished from G. variegata by fine spotted rather than ladder-like colour pattern, the white spots not margining the dark markings, slightly larger size, higher preanal pore counts and (in syntopy) rockdwelling rather than arboreal habits. Distinguished from G. purpurascens (2n=40c) by bolder spotted pattern, with larger black flecks and wavy lines and numerous white spots present in adults, and smaller size (max. SVL of G. purpurascens 65 mm).

Description. SVL 36–59 mm (mean 51.2, n= 46). Length of tail 46–49 mm (mean 92% SVL, n=3).

Rostral flat dorsally to weakly gabled, with a median groove descending to about 50% of the height of the scale. Nostril surrounded by rostral, first supralabial, two subequal postnasals and a larger supranasal. Internasals 0 to 3, mode 1. Supralabials 8–10, mode 9. Infralabials 8–10, mode 9. Two pairs of enlarged chin shields always present; a third pair sometimes present and contacting the second infralabial but not the third ( Fig. 6 ). Sublabial scale row starts at a notched infralabial, the second or third with similar frequencies. Lamellae under pad of fourth toe divided, 7 pairs showing obvious surface architecture of fine hairscales. Preanal pores in males 12–18 (mean=15, n=22), arranged in a chevron with median pore anteriormost.

In preservative ( Fig. 6 a), dorsum light grey to light brown with irregular dark spots, short wavy lines or streaks and numerous small, circular, white to pale grey spots. Spots usually forming regular transverse series around (original) tail but arranged more haphazardly on the head and body. White and black markings mostly not contacting one another.

In life ( Fig. 7 ), the dorsal background colour during the day can be considerably darker grey-brown to brown. At night, in common with most Gehyra , the contrast in the colour pattern is greatly reduced and paler overall.

Distribution. Rocky ranges and outcrops in the Gawler, Flinders and Mt Lofty Ranges of South Australia, extending eastwards into south-central New South Wales and southwest to the coast of the Great Australian Bight as far west as Ceduna and the Nuyts Archipelago (Fig. 8).

Comments. Wells & Wellington (1985) described three species of Gehyra (as Dactylopterus (Fitzinger 1843)) from western NSW. Dactyloperus annettae (type locality near Hillston, NSW), is a female that has greatly faded in preservative, but its colour pattern is still discernible, consisting of scattered small dark flecks that fail to form lines or continuous series. Dactyloperus lazelli , from near Griffith, NSW, is a male in much better condition, with a colour pattern of blackish speckles forming a reticulum over the entire head and body, with no continuous light-edged lines on the head or back, and 17 preanal pores. Neither specimen preserves any white markings, but this is a frequent artifact in preserved specimens of Gehyra . Their third new species, D. kingi , from Walgett, was synonymized by Bauer and Henle (1994) with G. variegata , but our examination of the type shows it to be indistinguishable from populations currently referred to Gehyra dubia (Macleay, 1877) ( Cogger 2000; King 1983).

The original descriptions of both D. annettae and D. lazelli list a series of character states for the two holotypes, but do not provide differential diagnoses. We regard these two specimens and the 2n=44f chromosome group as conspecific. Of the two, described on the same page in the same publication, we propose that the holotype of D. lazelli , with its better preserved colour pattern and diagnostic preanal pore count, is the more unambiguous choice in applying a name to the 2n=44f chromosome group ( Fig. 5 ). Accordingly we propose that the 2n=44f variegata should be known as Gehyra lazelli ( Wells & Wellington, 1985) , new combination, with Dactyloperus annettae as a junior synonym. The stated collecting locality, Mount Colley, could not be found in a gazetteer for any landmarks in the Cocoparra National Park or adjacent area. However there is a Mount Caley within the park, which may be the correct name for the type locality. Mount Caley is 25 km ENE of Griffith, at 34° 10’ 48’ S, 146° 17’ 23” E.

One other older name that we considered was Gecko grayi Steindachner, 1867 . The holotype specimen (NMW 19800:1) was said to have come from New South Wales, but with no other data ( Steindachner 1867; Cogger et al. 1983; Tiedemann et al. 1994). The name was regarded by Tiedemann & Häupl (1980) and Tiedemann et al (1994) as a synonym of G. australis Gray, 1845 , by Cogger et al. (1983) as a synonym of Gehyra variegata (Duméril & Bibron, 1836) , while Bauer & Henle (1994) considered it a possible senior synonym of Gehyra dubia (Macleay, 1877) . The specimen is in poor condition (photographs provided by F. Tiedemann and H.G. Cogger), with only traces of colour pattern visible on the body, and some weak dark transverse lines on the tail (detached). However the specimen can be excluded from either lazelli or variegata by virtue of its notched but mostly undivided toe pad lamellae and its chin shield arrangement ( Fig. 3 in Steindachner 1867, Tafel I), the third pair of chin shields being relatively large and wedged between the second and third infralabials, the sublabial row starting from a notched fourth infralabial. This combination is seen on some eastern Australian species presently referred to G. dubia and some G. catenata , but not on Gehyra from the south-eastern interior of Australia.

Distribution map of museum specimens identified as G. lazelli .

Gehyra in the south-eastern interior of Australia. Four nominal species are now known from this region, namely G. l a z e l l i, G. montium , G. purpurascens and G. variegata . All overlap to some degree in morphology and distribution, so that in most areas at least two and sometimes three species can occur in close proximity.

The difficulty in allocating specimens to species is made somewhat easier because three of the species, G. lazelli , G. montium and G. purpurascens , show a limited amount of morphological variation and are fairly tightly associated with particular microhabitats. The confusion is generally due to variation in G. variegata , which shows a wide variety of colour pattern variants and overlaps in size and habits with each of the other three. In practice, difficulty is experienced most often in distinguishing between juvenile and subadult G. purpurascens and G. variegata as these two may at times be found on the same tree, and G. lazelli and G. variegata , which overlap widely. The distinctions between G. lazelli and G. variegata are noted above in the re-description of G. lazelli , while most G. purpurascens can be recognized by a combination of a relatively broader rostral, fewer preanal pores and weaker colour pattern, especially the dark markings being small, numerous and scattered rather than bolder and more continuous. However, some preserved specimens from among these three species may not be certainly identifiable from morphology alone. Where species identity is essential, our data show that each of the three is readily separable by ND2 sequences.

Figures

FIGURE 3. Neighbour-joining network of Cavalli-Sforza chord distances among OTUs based on allozyme allele frequencies. See Appendix 1 for locations included in each OTU.

FIGURE 5. The type specimens of A) Dactyloperus lazelli and B) D. annettae.

FIGURE 6. Chin shield scalation and rostral-nasal scalation in Gehyra lazelli. A) tip of snout of SAMA R 56407 showing typical arrangement of scales. This specimen has one internasal scale wedged between the supranasals; rostral apex is almost flat in this specimen. B) chin shield arrangement of the holotype (AMS R 116972) showing one of the common arrangements. C) chin shields of another specimen (SAMA R 63427) showing an additional small chin shield pair contacting the second infralabial. In both, the sublabial row starts at the notched second infralabial. Abbreviations: cc: chin shields (excluding postmentals), il: infralabials, m: mental, pm: postmental, pn: postnasal, r: rostral, sbl: sublabials, sl: supralabials, sn: supranasal.

FIGURE 7. Live specimens of A) G. lazelli from the Middleback Range, SA, and B) G. variegata from Merbein, Victoria.