Nactus chrisaustini ZUG, 2020
Can you confirm these amateur observations of Nactus chrisaustini?
|Higher Taxa||Gekkonidae, Gekkota, Sauria, Squamata (lizards: geckos)|
|Common Names||E: Milne Bay Pygmy Slender-toed Gecko|
|Synonym||Nactus chrisaustini ZUG 2020: 60|
|Distribution||Papua New Guinea (Milne Bay: forest of the southern peninsula)|
Type locality: Look-out “Duabo” Pini Range, 10°25.071′S 150°18.413′E, 359 m asl, Milne Bay Province, Papua New Guinea.
|Types||Holotype. LSUMZ 123550, adult male, collected by Christopher C. Austin on 12 August 2006 (Figure 27).|
Paratypes. Adult males, LSUMZ 123532, from Alotau, Napatana Lodge grounds, 10°18.353′S 150°26.231′E, 6 m asl, Milne Bay Province, Papua New Guinea, collected by Christopher C. Austin on 7 August 2006, and LSUMZ 123535, with same collecting data as holotype; adult females, LSUMZ 123533–534 from Takwatakwai village, 10°19.537′S 150°02.259′E, 142 m asl, collected by Christopher C. Austin on 15–16 August 2006; adult female, MCZ R146098, from Alotau, collected by Fred Parker on 19 October 1974.
|Diagnosis||Definition. A bisexual taxon of geckos (Gekkoni- nae) of small adults (♀♀ 40–45 mm, ♂♂ 31–43 mm SVL) with smooth subcaudals, moderate-sized postmental scales (14–24, median 17), occasional postmental-infralabial (PmLab = 0–1, median 0.5) contact, moderate number of dorsal tubercle rows (12–15) and moderate number of tubercles (27–34, usually ≥29) in parasagittal row (TubRow), tubercles absent on dorsal surface of thigh and crus, and precloacal pores (5, 4–7) in males, females lack pores (0). Diagnostic summary in Table 8.|
Variation. Females and males display slight metric differences (adult ♀♀ 41.9, 39.6–45.1 mm; adult ♂♂ 37.8, 31.4– 43.3 mm SVL), although sharing similar proportions (total adult sample): TrunkL/SVL 42.4%, 40%–45%; HeadL/SVL 26.8%, 26%–29%; HeadW/SVL 17.1%, 16%–19%; HeadW/HeadL 63.6%, 61%–67%; EyeD/SVL 6.4%, 6%–8%; EyeD/HeadL 23.9%, 21%–30%; NarEye/HeadL 35.1%, 30%–43%; Inter- orb/HeadL 27.8%, 24%–40%; SnW/HeadL 15.8%, 15%–17%.
Typical head scale pattern of small, granular scales except for those bordering nares and mouth. Snout with large rostral scale bearing middorsal cleft posteriorly; supranasals moderate sized, usually in contact on midline or separated by small granu- lar scale (internasal); large supralabials (3, 3–4) and infralabi- als (3, 3–4) in front of anterior edge of orbit, first supra- and infralabial largest of respective series. Chin with large trapezoi- dal mental and small to moderate to large postmentals (Postm = 17, 14–24) and variably genial scale between postmental and first supralabial (0.5, 0–1 PmLab); dorsally, trunk with 14, 12–15 (DorsTub) enlarged tubercles transversely on dorsum and with 30, 27–34 tubercles (TubRow) longitudinally along trunk; 9, 8–10 tubercle rows transversely between hindlimbs (TubHip). Usually, no enlarged tubercles on crus and femur (TubHindl = 0, 0–2). Tail with small uniform scales dorsally and laterally, ven- trally with uniform, small smooth scales (Subcaud = 1). Usually, pair of cloacal spurs (2, 1–2 CloacS) on each side. Ventral scales from chin to vent small, granular, somewhat larger on chest and abdomen. Precloacal pores, males 5, 4–7, females 0. Forefoot with narrow digits, their lengths usually 3≈4>2≈5>1; 14, 12–14 lamellae beneath fourth digit (4FingLm), 4.5, 4–5 scale rows on palm; hindfoot with narrow digits, their lengths typically 3≈4>2≈5>1; 17.5, 17–19 lamellae beneath fourth toe (4ToeLm).
Coloration in life not reported. In alcohol, color and pattern match the general description of the holotype. The dorsal trunk pattern of spots varies from faded to dark and ranges from 5 to 6 pairs from between shoulders to sacrum.
|Comment||Distribution: see map in Zug 2020: 53 (Fig. 22).|
|Etymology||The specific name chrisaustini recognizes the discoverer, Christopher C. Austin, of this diminutive species. The proposal of this name also recognizes his continuing research into the relationships and biology of the New Guinea herpetofauna and our friendship.|