Gerrhopilus lestes KRAUS, 2017
Can you confirm these amateur observations of Gerrhopilus lestes?
|Higher Taxa||Gerrhopilidae, Typhlopoidea, Serpentes, Squamata (snakes)|
|Synonym||Gerrhopilus lestes KRAUS 2017|
|Distribution||Papua New Guinea (New Ireland Province)|
Type locality: Weitin River Valley, 13 km N, 10.5 km W of river mouth (4.5035° S, 152.9374° E, 240 m a.s.l.), New Ireland, New Ireland Province, Papua New Guinea.
|Types||Holotype: BPBM 11904, Sex unknown (specimen undissected), (field number AA14090), collected by A. Allison on 18 January 1994.|
|Diagnosis||Diagnosis. This species belongs to Gerrhopilus based on the presence of head glands in the centers of the anterior head shields in addition to their anterior margins (McDowell 1974; Wallach 1996b). A relatively robust (L/ M = 76) species of Gerrhopilus having the unique combination of head glands dispersed among the rostral, superior nasal, preocular, ocular, and supraocular scales but absent from the frontal, prefrontal, and all supralabials, a rostrate snout with a transverse keel on the ventral margin of the rostral that lies dorsal to the rictus, angle of pre- oral snout in lateral aspect inclined at an approximately 10° angle from the horizontal, distinct pupil in the eye, longitudinal scale rows 26/24/20, transverse scale rows posterior to the rostral 722, supralabial imbrication pattern T-V, subocular scale one, presubocular scale absent, subcaudal scales 25, L/W ratio 55, and an unpigmented rostral followed sequentially by dark-brown head scales and then paler-brown body scales, giving the face a masked appearance. Refer to Table 1 for additional diagnostic qualitative and quantitative features.|
Comparisons. Gerrhopilus lestes may be distinguished from all other members of this genus except G. addisoni, G. depressiceps, G. eurydice, G. mcdowelli, and G. persephone in having a transverse keel on the ventral margin of the rostral, which gives the snout a beaked appearance in lateral aspect, and in having a posterior reduction of longitudinal scale rows from head to vent. It may be distinguished from G. addisoni, G. depressiceps, and G. eurydice in having 26 scale rows around the body just posterior to the head (vs. 24 in G. addisoni, G. depressiceps, and G. eurydice) and having the snout angled at a ca. 10° angle from the horizontal, leaving the ventral keel of the rostral superior to the rictus. Gerrhopilus lestes differs from G. mcdowelli in having a much greater number of mid-dorsal scale rows (722 vs. 431–464 in G. mcdowelli) and the rostral keel pointing directly downward (vs. pointing anteroventrally in G. mcdowelli); and from G. persephone in its stouter habitus (L/ W = 55 vs. 82 in G. persephone), lesser inclination of the pre-oral snout from the horizontal (ca. 10° angle vs. ca. 25° angle in G. persephone), relatively smaller eye (L/E = 745 vs. 564 in G. persephone), and relatively longer pre- oral snout (PSN/SNW = 0.68 vs. 0.44 in G. persephone). The color pattern of an unpigmented rostral followed sequentially by dark-brown head scales and then paler-brown body scales immediately distinguishes G. lestes from all other Gerrhopilus species with a ventrally keeled rostral.
|Etymology||The trivial epithet is a masculine Greek noun in apposition meaning “thief,” an allusion to the mask-like color pattern across the head.|