Systematics of the blindsnakes (Serpentes: Scolecophidia: Typhlopoidea) based on molecular and morphological evidence
Author
Pyron, Robert Alexander
Author
Wallach, Van
text
Zootaxa
2014
3829
1
1
81
journal article
36820
10.11646/zootaxa.3829.1.1
a4b69269-5a4c-4b5b-9f89-6b314d3ba284
1175-5326
286556
75210CDC-AC6A-4624-A6F1-1BC969BC7CAA
Grypotyphlops
Peters, 1881
Type
species.
Onychocephalus acutus
Duméril & Bibron, 1844
Species content.
Grypotyphlops acutus
.
Diagnosis.
Grypotyphlops
can be distinguished from all other typhlopoids by the combination of a T-0
SIP
, dorsal and lateral snout profiles acutely pointed, and subocular present. Large-sized (total length
115–631 mm
), stout- to slender-bodied (length/width ratio 38–79) snakes with 24–34 scale rows (with reduction), 448–526 total middorsals, short tail (0.8–1.9% total length) with 7–13 subcaudals (length/width ratio 0.8–1.5), and apical spine absent. Broad rostral (0.61–0.80 head width), inferior nasal suture in contact with first or second supralabial, preocular in contact with second and third supralabials, small eyespot present under nasal shield, T-0
SIP
, and postoculars 3–4. Lateral tongue papillae present; left lung absent, tracheal, cardiac and right lungs multicameral (with 32–38 + 4–7 + 3–8 chambers, respectively); testes unsegmented; hemipenis eversible, lacking retrocloacal sacs; and rectal caecum moderate (2.5–2.8% SVL). Coloration brown, light brown, tan or golden-brown dorsally with immaculate gold to yellow venter, and rostral gold to yellow, lighter than dorsum.
Phylogenetic definition.
This genus is currently monotypic, but would include any newly discovered species more closely related to
Grypotyphlops acutus
than to any of the 15
type
species of the other typhlopid genera listed here.
Etymology.
Likely from the Greek for hooked nose
(grypos)
, referring to the "beaked" appearance of
Grypotyphlops acutus
.
Distribution.
Peninsular
India
.
Remarks.
The genus
Grypotyphlops
was resurrected for
Onychocephalus acutus
(
Wallach 2003
)
, and is thus the currently recognized, valid genus for the species, which was previously placed in
Rhinotyphlops
(
McDiarmid
et al.
1999
)
. The species
Onychocephalus unilineatus
Duméril & Bibron, 1844
was considered
incertae sedis
by
Dixon & Hendricks (1979)
and
McDiarmid
et al.
(1999)
, who questioned the locality of Cayenne,
French Guiana
. The
type
(MNHN 1064) has been re-examined and shown to be a synonym of
Gr. acutus
(
Wallach 2003
)
. The same is true for the
type
(IRSNB 2017) of
Typhlops psittacus
, another species described with erroneous locality data (
Werner 1903
;
Wallach 1994
). This genus bears a resemblance, both internal and external, to some species of
Letheobia
(Tables 2, 3;
Wallach 1994
,
2003
), and may thus form part of an Africa-India clade, reflecting the shared Gondwanan biogeographic history of typhlopids (
Vidal
et al.
2010
). We thus place it in Afrotyphlopinae.