Revised key to the Indian species of Rhinophis

This is an updated version of the key presented by Sampaio et al. (2020), revised with the addition of new information on phenotypic variation in R. fergusonianus. All six species are endemic to peninsular India and are the only members of this genus known to occur in India.

1 Number of dorsal scale rows slightly behind midbody 17...................................................... 2

- Number of dorsal scale rows slightly behind midbody 15...................................................... 3

2 Ventral shields fewer than 160............................................................... R. travancoricus

- Ventral shields more than 180.................................................................... R. goweri

3 Ventral shields> 215...................................................................... R. melanoleucus

- Ventral shields <215.................................................................................. 4

4 Ventral surface with dark blotches, often in irregular, staggered, transverse half-bands (or an irregular midline zigzag); verified localities <200 m elevation................................................................. R. fergusonianus

- Ventral surface with irregular dark speckles or spots; verified localities> 700 m elevation........................... 5

5 venter background colour bright red in life (paler, more orange-yellow in smaller specimens)............... R. sanguineus

- venter whitish (to pale orange anteriorly and posteriorly) with dark markings......................... R. karinthandani