Gerrhopilus suturalis (BRONGERSMA, 1934)
Can you confirm these amateur observations of Gerrhopilus suturalis?
|Higher Taxa||Gerrhopilidae, Typhlopoidea, Serpentes, Squamata (snakes)|
|Synonym||Typhlops ater suturalis BRONGERSMA 1934: 196|
Gerrhopilus suturalis — WYNN 2021
|Distribution||Indonesia (Halmahera eastward to western New Guinea), Papua New Guinea|
Type locality: Andai, New Guinea
|Reproduction||oviparous (by implication)|
|Types||Holotype: RMNH 6297; paratypes: RMNH from Waigeoe, Salawatti, Halmahera|
|Diagnosis||Description: “Snout rounded, nostril lateral. Rostral narrowly rounded, or more or less pointed behind, not reaching the level of the eyes. Nasal completely divided, the cleft proceeding from the second upper labial. Preocular present, narrower than the ocular, separated from the upper labials by a subocular. Ocular in contact with the third and fourth upper labials. Eyes distinct. Four upper labials. 18 rows of scales round the middle of the body. Diameter of body contained 45.1—51.1 times in the total length; length of tail contained 28—36 times in the total length. Tail 1.3—1.8 times as long as broad.|
Colour (in alcohol): back uniformly black, or with indications of darker and lighter lines, lighter below.” (Brongersma 1934: 196).
Discussion in Wynn 2021: “G. a. ater and G. a. suturalis do not occur together (G. a. ater being known only from Java, and G. a. suturalis known from Halmahera eastward to western New Guinea), and several other characters can distinguish the two taxa. In the five G. a. ater for which I have both a total length and midbody diameter (RMNH 11436, RMNH uncataloged specimen, RMNH uncataloged specimen, ZMB 4053, and ZMB 6931, all from Java), the midbody diameter is 1.7%–2.1% total length. The ratio is 2.4%–3.1% in the six G. a. suturalis for which I have these data (all the type specimens except MCZ 33503). In addition, the color pattern of G. a. ater and G. a. suturalis differs. In G. a. ater, both the dorsum and venter are pigmented with melanophores. The venter is slightly lighter than the dorsum, with a gradual transi- tion in coloration from dorsum to venter. Gerrhopilus a. suturalis has similar dorsal and ventral pigmentation, but rather than a gradual dorsal-to-ventral transition, there is a distinct change from dark dorsal pigmentation to lighter ventral pigmentation. Typically, the middorsal row and the five rows to either side are darkly pigmented, and the midventral row and three rows to either side of it are distinctly lighter, with the transition from dark to light usually occurring between the fifth and sixth scale rows lateral to the middorsal row. In addition, the tail in G. a. ater tapers little along its length and is then abruptly rounded near its tip, with a terminal scale that is more rounded than obtusely cone-shaped and having only a minute spine or no spine at all at its tip. In G. a. suturalis, the tail typically has little taper over the first half of its length, but then tapers gradually over the last half of its length, and the terminal scale is obtusely angled with a small, but more prominent spine. Gerrhopilus a. ater also has only one postocular scale on each side of the head, whereas G. a. suturalis has two postocular scales on each side. These differences warrant the recognition of G. suturalis as a distinct species from G. ater, and I remove G. suturalis from the synonymy of G. ater here.”
|Comment||Synonymy: Typhlops ater suturalis has been considered as a synonym of Typhlops ater but was revalidated by Wynn 2021.|