Hebius modestus


Hebius modestus, commonly known as the modest keelback or Günther's keelback, is a species of natricine snake endemic to Asia.

Geographic range

Confirmed range:
Disputed records: Historical reports from Vietnam, Cambodia, Laos, Thailand, and Guangdong/Guizhou are questionable or misidentifications. It possibly occurs in Bhutan.
The type locality is Khasi Hills, India.

Description

Adults may attain 60 cm in overall length; tail length 18 cm.
Dorsum: Dark grayish-brown to olive brown, scattered with black spots or blotches. A dorsolateral series of ochre-yellow, orange-brown, or reddish-brown stripes extends from the nape to the tail base on the 4th–7th dorsal scale rows. Postocular streak is absent.
Ventrally it may be yellowish with a, or yellowish in the middle and blackish on the sides, or almost entirely blackish.
Venter: Pale ochre-brown centrally, broadly edged with dark brown or blackish on the outer quarter of ventrals. Series of blackish spots on each side of the ventrals.
Head: Labial sutures black; short, broad, horizontal pale streaks on the neck sides before the dorsolateral stripe along with a streak on the nape, behind the parietal scales.

Scalation

  • Dorsal scales: 19-19-17 rows, weakly keeled at midbody and posteriorly; smooth on first dorsal scale row
  • Ventrals: 143–163 in males, 154–168 in females
  • Anal: Divided
  • Subcaudals: 104–122, divided
  • Supralabials: 8–9; 3rd–5th entering the eye
  • Infralabials: 8–9
  • Anterior temporals: 1 or rarely 2; rectangular and elongate
  • Preoculars: 1
  • Maxillary teeth: 27–30, with the last two moderately enlarged

Generic revisions

The species was initially placed in the genus Tropidonotus, later moved to Amphiesma but in 2014 it was transferred to Hebius by Guo et al. based on molecular and morphological data.

Differentiation from congeners

H. modestus can be distinguished from similar species by:

Habitat

In India this species is found in forests at altitudes of 600-1,500 m.