Christinus marmoratus (GRAY, 1845)
Can you confirm these amateur observations of Christinus marmoratus?
|Higher Taxa||Gekkonidae, Gekkota, Sauria, Squamata (lizards: geckos)|
|Common Names||Marbled Southern Gecko, Marbled Gecko|
|Synonym||Phyllodactylus porphyreus DUMÉRIL & BIBRON 1836 (partim)|
Phyllodactylus Peronii FITZINGER 1843: 95
Diplodactylus marmoratus GRAY 1845
Goniodactylus australis GRAY 1845
Gonatodes australis — BOULENGER 1885: 72 (?)
Phyllodactylus marmoratus — BOULENGER 1885: 88
Phyllodactylus macrodactylus BOULENGER 1885: 89
Phyllodactylus affinis — BOULENGER 1885: 89
Phyllodactylus marmoratus — LOVERIDGE 1934
Phyllodactylus marmoratus — COGGER 1983
Christinus marmoratus — WELLS & WELLINGTON 1984
Christinus biggsae WELLS & WELLINGTON 1985: 10
Phyllodactylus marmoratus marmoratus — STORR 1987
Christinus marmoratus marmoratus — RÖSLER 2000: 62
Christinus marmoratus macrodactylus — RÖSLER 2000: 62
Christinus marmoratus — COGGER 2000: 208
Christinus marmoratus — WILSON & SWAN 2010: 60
Christinus marmoratus — HEINICKE et al. 2014
|Distribution||Australia (New South Wales, South Australia, Victoria, Western Australia)|
Type locality: restricted to West- and South Australia (Kangaroo Island, Swan River, Freemantle, Champion Bay, Houtman’s Abrolhos, Norfolk Island, Aneitum).
Type locality: “Australia” and “Houtman’s Abrollos” [GRAY 1845].
Type locality: Australia [macrodactylus].
|Types||Lectotype: BMNH xxi.9.a. Designated by Wells & Wellington (1985) (marmoratus)|
Syntypes: MNHN 6734, 6734A [Peronii]
Holotype: BMNH 188.8.131.52 [affinis]
Holotype: BMNH xxii.86a [australis]
Syntypes: BMNH 184.108.40.206 [macrodactylus]
Holotype: AMS 116977 [biggsae]
|Diagnosis||Definition (genus). Christinus is distinguishable from all other geckos based on the following combination of characters: size large (70–80 mm max. SVL), with a moderately pro- portioned head, cylindrical body, and round, tapering tail. Digits are free and bear a single pair of dilated terminal adhesive pads (‘leaf toes’); claws are present on all digits. Dorsal scalation consists of small, smooth granules. Preanal pores are absent; 3–4 cloacal spurs are present. The eye bears a vertical pupil with crenate margins. The skull dis- plays no co-ossification with the overlying skin. Nasals are fused; frontal single; parietal paired; stapes imperforate; 14 scleral ossicles; 12-13 premaxillary and between 30 and 39 dentary tooth loci; hyoid with second ceratobranchial carti- lages. There are 27–28 presacral vertebrae and one pair of cloacal bones. The phalangeal formula is 2-3-4-5-3 (manus)/2-3-4-5-4 (pes); paraphalangeal elements are absent.|
Four cranial osteological apomorphies were found for Christinus marmoratus: lateral vertex of the postorbito- frontal located anterior to the frontoparietal suture (95-00, Fig. 28); length of the exposed portion of the frontal shorter than the width of the frontoparietal suture (127-20, Fig. 28); number of premaxillary tooth loci 12 or 13 (368-00).
Christinus has more presacral vertebrae than any other genus of leaf-toed gecko. It can be distinguished from all other Australian leaf-toed gecko genera (which belong to the family Diplodactylidae) based on possession of enlarged scales on the dorsal surface of the broadened ter- minal adhesive pads, as well as all traits that distinguish gekkonids from diplodactylids (including L-shaped meatal closure muscles, hard-shelled eggs, and a single centre of ossification in the premaxilla; Kluge, 1987) [HEINICKE et al. 2014]
Diagnosis (Christinus): The genus Christinus Is characterised by the following: Round rostral and mental, with postmentals enlarged; enlarged lablals; no preanal pores; digits lay flat, long and thin, somewhat depressed; distal expansion of digits form distinct pads; apical sub-digital lamellae as large pair; sub-digital lamellae enlarged but smaller than apical; digits have dorsal scales which are larger distally than at base; all digits possess retractile claws which fit into a groove in the apical lamellae; dorsal scales small, smooth and homogeneous; clutch size two, but practices communal egg-laying behaviour; size up to 80 mm SVL. A relictual group of endemics confined to southern Australia and the Lord Howe and Norfolk Island groups. A colour plate of Christinus marmoratus is in Cogger, (1983, pI. 85) and a plate of Christinus guentheri can be found in Cogger, Sadlier and Cameron, (1983) [from WELLS & WELLINGTON 1984].
|Comment||Karyotype: Christinus marmoratus marmoratus is a composite of two chromosomally distinct, but morphologically very similar taxa.|
Type species: Diplodactylus marmoratus GRAY 1845 is the type species of the genus Christinus WELLS & WELLINGTON 1994. See comments in Bauer 1994 for a discussion of nomenclatorial issues.
Subspecies: Christinus marmoratus macrodactylus is not recognized as subspecies any more (Glenn Shea, pers. comm. Feb 2019).
|Etymology||Etymology (Christinus): Named for Miss Christine Biggs of London.|