Gekko crombota is one of ten currently recognized, endemic species of Gekko in the Philippines. This species is part of a unique group of island-endemic species that are distributed in the Babuyan and Batanes island groups in the extreme northern Philippines. Six unique island endemic species have been discussed in the literature; however, only three of these species are currently described (Gekko crombota, Gekko rossi, and Gekko porosus). Gekko crombota is known only from the small island of Babuyan Claro in the Babuyan Island Group in the northern Philippines.
Recent studies and increased survey efforts throughout the Philippines have resulted in a dramatic increase in the diversity of gekkonid lizards in the country. The archipelago is now known to support ten genera and at least 48 described species in the genera Cyrtodactylus (9 species), Gekko (12–13), Gehyra (1), Hemidactylus (5; including platyurus, a species formerly assigned to Cosymbotus), Hemiphyllodactylus (2), Lepidodactylus (6), Luperosaurus (8), Pseudogekko (4), and Ptychozoon (1) (Taylor, 1922a,b; Brown and Alcala, 1978; Brown and Diesmos, 2000; Brown et al., 1997, 1999, 2007, 2008, 2009, in press; Gaulke et al., 2007; Linkem et al., 2010; Welton et al., 2009, 2010a, b; Zug, 2010).
Ten species of Gekko are considered endemic to the archipelago (Brown et al., 2009; Linkem et al., 2010) and two additional species with broad geographic distributions (G. gecko, G. monarchus) are also known from the country (Taylor, 1922a, b; Brown and Alcala, 1978; Ota et al., 1989). The ten endemic Philippine species are G. athymus, G. carusadensis, G. crombota, G. ernstkelleri, G. gigante, G. mindorensis, G. palawanensis, G. porosus, G. romblon, and G. rossi. These species represent a considerable range in body size, general appearance, and ecological attributes, but all possess the following combination of morphological traits: (1) body size moderate, with relatively long, slender limbs; (2) near complete absence of interdigital webbing or cutaneous body expansions; (3) dorsal tubercles arranged in longitudinal rows on the dorsum (except for G. athymus, in which dorsal tuberculation is absent); (4) scales of dorsum between tubercle rows minute, non-imbricate; (5) scales of venter enlarged, imbricate, flat; (6) differentiated postmentals elongate; and (7) subcaudals enlarged, plate-like (Brown and Alcala, 1978; Brown et al., 2007, 2008, 2009).
Dorsal ground coloration dark purplish-gray to yellowish-brown, with indistinct dark gray to black blotches; dorsum with six light cream tri-lobed bars traversing the axilla-groin region, each bordered anteriorly by an accompanying thin transverse wavy black band (the darkest above insertion of hind limbs) and posteriorly by normal trunk ground coloration. Dorsal nuchal region and posterior portions of head very similar to trunk coloration but with distinct, round, cream-colored spots; similar cream bars radiate out from the orbit; postrictal region flat gray; labial scales purplish-gray with cream spots on every third labial scale; darker black blotches and flecks congregate on snout, interorbital region, and parietal region; infralabial region and chin gray to light gray; snout scale purplish gray; gular region light gray to brownish-tan. Dorsal surfaces of limbs light gray with numerous dark brown flecks; dorsal surfaces of digits dark gray with slightly lighter claws; dorsal and lateral portions of tail banded alternating dark gray and cream (corresponding to tail annuli); distal autotomy regrowth dark brown. Ventral body and limbs yellow with scattered gray and dark brown flecks; preanofemoral region bright yellow with dark orange pores; palmar and plantar surfaces of manus and pes yellowish with light gray subdigital scansors; ventral tail cream with brown transverse bars, and solid brown ventral coloration distal to autotomy scar and subsequent regrowth.
Gekko crombota differs from all other species of Philippine Gekko (i.e., G. athymus, G. ernstkelleri, G. gecko, G. gigante, G. mindorensis, G. monarchus, G. palawanensis, G. porosus, and G. romblon) in the following combination of features (1) large body size (SVL 85.5–117.9 for adult males; 85.1–106.9 mm for females); (2) dorsum medium brown to gray, marked with cream colored, transverse, tri-lobed bars with a black anterior border; (3) high numbers of dorsal body scales (107–132 transverse midbody scales; 192–226 paravertebrals); (4) high numbers of sharply conical dorsal body tubercle rows (17–21 midbody; 27–33 paravertebrally); (5) preanofemorals arranged in a non-continuous series (preanals and femoral pore-bearing scale series separated by one or two non-pored scales in 75% of specimens) of 58–74 differentiated, slightly enlarged scales.
Gekko crombota differs from its phenotypically most similar Philippine congener, Gekko porosus (Batan and Itbayat islands, of the Batanes islands group, north of the Babuyas), attainment of a larger maximum male body size (males: SVL 85.5–117.9 vs. 91.0–96.7 in G. porosus); swollen (presumptively hypertrophied) adductor and temporal musculature of the head leading to a wider, vaguely triangular head shape (versus adductor and temporal musculature distinctly less enlarge in G. porosus, head more slender); brown to gray dorsal coloration, interrupted by distinct, tri-lobed, cream-colored bars (versus indistinct dark transverse bands and/or circular vertebral blotches in G. porosus); a greater number (107–132) of transverse midbody dorsal scales (vs. 88–103 in G. porosus); a greater number (192–226) of paravertebral scales (vs. 173–191 in G. porosus); the presence of sharply protuberant (vs. merely convex or slightly raised) dorsal tubercles, a greater number (17–21) of midbody dorsal tubercle rows (vs. 15–17 in G. porosus) and a greater number (27–33) of paravertebral tubercle rows (vs. 17–24); separation (1 or 2 undifferentiated scales) between the preanal and femoral series of pore-bearing scales (in 75% of specimens; absent in G. porosus); the presence of fewer (58–74) preanofemoral pore-bearing scales (vs. 74–82 in G. porosus); and the absence of a modified distal femoral pore-bearing patch (vs. present in G. porosus, composed of a short series of 2 or 3 rows of pore-bearing scales.
Gekko crombota is known only from Babuyan Claro Island in the northern Philippines.
Our impression is that the new species is very common at the type locality. No vocalizations by this species were heard during our brief visits to the type locality. The only other gekkonids encountered during our three night stay on Babuyan Claro were Hemidactylus frenatus, Cyrtodactylus philippinicus, and Luperosaurus macgregori
The specific epithet crombota is a group of letters derived from the names Crombie and Ota, and treated as a noun in apposition. We employ the amalgam combota to jointly honor Ronald Crombie and Hidetoshi Ota in recognition of their collaborative survey efforts in the Babuyan Islands (Ota and Crombie, 1989; Ota and Ross, 1994) and their continued work on the gekkonid fauna of this archipelago (H. Ota and R. Crombie, unpublished data).
Gekko crombota is recognized to occur in the Babuyan Island Group of the extreme northern Philippines.
it was collected low (< 3 m) on trunks and buttresses in primary dipterocarp forest at low elevations, close to the island’s coast.
SVL 85.5–117.9 for adult males; 85.1–106.9 mm for females
Babuyan Claro Island, Babuyan Island Group, northern Philippines
The Babuyan Claro gecko (Gekko crombota) is a species of gecko. It is endemic to Babuyan Island in the Philippines.[1]
The Babuyan Claro gecko (Gekko crombota) is a species of gecko. It is endemic to Babuyan Island in the Philippines.
