Diporiphora granulifera, MELVILLE & DATE & HORNER & Doughty, 2019

MELVILLE, JANE, DATE, KATIE SMITH, HORNER, PAUL & Doughty, Paul, 2019, Taxonomic revision of dragon lizards in the genus Diporiphora (Reptilia: Agamidae) from the Australian monsoonal tropics, Memoirs of Museum Victoria 78, pp. 23-55 : 48-50

Diporiphora granulifera sp. nov.

ZooBank LSID: http://zoobank.org/ urn:lsid:zoobank.org:act:

B6B3DAEB-9D8E-4D5A-A53B-04BF6962C3B1

Common name. Granulated two-lined dragon.

Figure 20 , Tables 3, 4

Holotype. QM J96362 (formerly NMV D74060 ) (adult male), Downs Road, 2 km from Barkly Highway , Queensland (20.3714° S, 139.1529° E). Collected by K. Smith in October 2005.

Paratypes. NMV D74047 (adult female), Lawn Hill Station , Queensland (18.6536° S, 138.5653° E) ; NMV D74054 (adult male), Carpentaria Highway, west of Burketown , Queensland (18.0242° S, 139.0077° E) ; NMV D74062 (adult male), Downs Road, 2 km from Barkly Highway , Queensland (20.3717° S, 139.1525° E) .

Diagnosis. Medium-large species (to 68 mm SVL) with a very long tail (>2.5 × SVL). Gular fold absent, post-auricular fold weak and scapular fold strong. Granular scales in axilla, extending over arm and along the full length of the scapular fold. Scales on neck anterior to scapular fold small and slightly granular. Outer scale row in dorsolateral stripes have raised posterior edge, particularly over shoulder, giving strong demarcation between dorsal and lateral surfaces. Pre-cloacal pores 4–6 (usually 4); femoral pores 0.

Description of holotype. Male; 65 mm SVL; 176 mm tail length. Medium-large Diporiphora , moderately gracile with long limbs and very long tail. One canine on either side of upper jaw. Gular fold absent. Post-auricular and scapular folds strong. Dorsal scales strongly keeled, relatively homogenous. Longitudinal series of raised but unenlarged pale dorsolateral scales at the shoulder, extending down posteriorly along dorsum to base of tail. Scales on flanks homogeneous, although changing from small granular scales in axilla to small but not granular scales on the posterior two-thirds of flanks. Lacking cluster of spinose scales at rear of head on the post-auricular fold, lacks spinose scales limbs or tail. Small granular scales in axilla, extending up over shoulder and along under full extent of the scapular fold. Scales on sides of neck anterior to scapular fold small and slightly granular. Ventral scales strongly keeled. Pre-cloacal pores 6; femoral pores 0.

Dorsum light brown with little patterning. Faint broad grey vertebral stripe; well-defined cream dorsolateral stripes running from back of head to base of tail and associated with raised but not enlarged longitudinal scales. Dark transverse bands absent. Head relatively plain with little patterning; labials similar colour to rest of head, although posterior third paler than anterior; poorly defined, faint pale stripe from eye to top of ear. Dark smudge on posterior of tympanum absent. On flanks, granular scales in axilla are dark brown then transition posteriorly into cream, grey and light brown with little patterning; flanks have darker dorsal patterning above and pale cream ventrally; flecked with a few light brown scattered scales. Lateral stripe between axilla and groin absent. Dark patch in axilla extending up over shoulder and down full length of scapular fold. Arms lack dark banding. No patterning on legs, faint banding on anterior third of tail with dark bands wider than pale bands. Ventral surface cream with no patterning.

Variation. 44–68 mm SVL; 121–179 mm tail length. Very long tail, ranging from 2.7–3.0 × SVL. Gular fold always absent, post-auricular fold weak to present, scapular fold strong, extending onto edges of ventrum. In some animals, enlarged scales on post-auricular fold has an enlarged cluster of scales at the ventral extent but without a single spinous scale. Pre-cloacal pores variable from 4–6 (usually 4); femoral pores always 0.

Variable patterning from strongly patterned individuals to plain individuals. In patterned individuals, approximately 6–8 dark brown bands slightly offset to each other on either side of a broad undefined greyish vertebral stripe. Banding extends onto tail, fading out half way down tail. Well-defined pale dorsolateral stripes, running from back of head to base of tail and becoming interrupted by banding pattern of tail. Flanks have a faint, poorly defined light brown lateral stripe, with darker dorsal patterning above and pale cream below. Flanks flecked with a few light brown scattered scales. In more plain individuals, pale dorsolateral stripes from neck onto base of tail. Granular scales in axilla are dark brown; flanks cream, grey or light brown with little patterning. No white markings on face, labial scales speckled with light brown flecks. Faint or no banding on limbs. Ventral surface cream, usually plain but some individuals have faint dark flecking on ventral surface of head. Males with breeding colouration tend to lose some of their dorsal patterning, having a large black patch in axilla extending on to shoulder and some having a pink flush on base of tail.

Etymology. Named for the extensive granulated scales on sides of body.

Distribution and ecology. Restricted to the far north-west Gulf of Carpentaria region of Queensland. More collecting is required to determine how far east this species extends and whether it extends west into the NT. A habitat generalist occurring in tropical savannah woodlands and grasslands. Has been observed perching on low vegetation, rocks or termite mounds.

Comparison to other species. The distribution of D. granulifera sp. nov. contacts a number of other Diporiphora species in the western Gulf of Carpentaria region. Very similar morphologically to D. carpentariensis sp. nov. and it remains unclear whether they come into contact in the central Gulf of Carpentaria region, but can be distinguished from this species in lacking or having weak spinose scales on the post-auricular fold and in having granular scales extending anteriorly to the scapular fold, with scales on the sides of neck more homogenous and outer scale row in dorsolateral stripes having raised trailing edge, particularly over shoulder, giving strong definition between dorsal and lateral surface. Differs from D. magna in having granular scales extending over shoulder and along scapular fold, slightly onto ventral surface of neck. Differs from D. lalliae in lacking a gular fold. Can be distinguished from D. sobria in lacking a gular fold and femoral pores, and having single canines on either side of the upper jaw.

Remarks. Although very similar morphologically to D. carpentariensis sp. nov., the genetic analysis of Smith et al. (2011) across multiple genes distinguished these two species as divergent lineages that are not each other’s closest relatives. It remains to be determined if these two species contact in the central Gulf of Carpentaria region.

Recent unpublished phylogenomic research using singlenucleotide polymorphisms shows that D. granulifera sp. nov. is highly divergent and genetically distinguishable from D. magna (as defined above) (J. Fenker, unpublished data). However, there is evidence of gene flow and mtDNA introgression between these two species in areas of contact, including along the Barkly Highway, Queensland. The holotype (QM J96362), which was included in this genomic analysis, was confirmed as being D. granulifera sp. nov. and is not a hybrid animal, with no evidence of genomic contribution from D. magna .

Diporiphora granulifera sp. nov. contributes to a small number of endemic lizard and frog species from the Gulf of Carpentaria region, including Cryptoblepharus zoticus Horner , Oedura bella Oliver and Doughty and Litoria electrica Ingram and Corben. Further genetic and morphological work on species that span the Gulf of Carpentaria area may reveal further interesting phylogenetic patterns in this poorly sampled region.

Figures

Figure 20. Diporiphora granulifera sp. nov.: a, in life, Lawn Hill, Queensland (photo: S. Wilson). b, c, d, dorsal, ventral and lateral (head) views of holotype QM J96362 (formerly NMV D74060) Downs Road, 2 km from Barkly Highway, Queensland.