About Gerarda prevostiana (Eydoux & Gervais, 1837)
Gerarda prevostiana (Eydoux & Gervais, 1837) displays the following scalation characteristics: The frontal scale is slightly longer than it is broad, and shorter than both its distance to the tip of the snout and the length of the parietals. The loreal scale is slightly longer than it is deep, and a little smaller than the nasal scale. This species has one preocular scale and two postocular scales. Temporal scales are arranged in a 1+2 pattern. There are eight upper labial scales, with the fourth upper labial extending into the eye socket. Four lower labial scales make contact with the anterior chin shields. The anterior chin shields are much larger than the posterior chin shields. Dorsal scales are arranged in 17 rows at midbody. Ventral scales number between 146 and 158. The anal scale is divided. Subcaudal scales number between 31 and 34. The dorsal body is uniformly dark olive, with the three outermost scale rows colored whitish. The upper lip is white, while the rostral scale is dark olive. Ventral and subcaudal scales are whitish, with dark edges. Total body length reaches 41 cm (16 inches), with the tail alone measuring 5 cm (2 inches) long. Geographically, G. prevostiana occurs in coastal regions stretching from western India (Mumbai) to the eastern Philippines. It is found in India (including the Andaman Islands), Sri Lanka, Bangladesh, Myanmar, Thailand, Peninsular Malaysia, Singapore, Cambodia, Indonesia (Borneo: Sarawak), and the Philippines (Luzon). Its preferred natural habitat is coastal areas, particularly regions containing mangrove forest. G. prevostiana is ovoviviparous.
