Reptiles and Amphibians of Thailand

Thailand's Snakes, Lizards, Turtles, and Frogs

Orange-necked Keelback

Rhabdophis flaviceps

This species is found in Thailand, but not within Bangkok itself
Orange-necked Keelback Orangeneck Orange-lipped Rhabdophis flaviceps Macropisthodon งูรังแหหัวแดง
Orange-necked Keelback in Sumatra (© Orion Herp Adventures)

English name: Orange-necked Keelback (aka: “Orangeneck Keelback”, “Orange-lipped Keelback”)
Scientific name: Rhabdophis flaviceps (formerly Macropisthodon flaviceps)
Thai name: งูรังแหหัวแดง (Ngu Rang Hae Hua Daeng)

Description: To 85cmm long. A robust snake with distinct head. Body is gray to brown with pale crossbars, the frontmost of which is significantly broader and usually orange or orangish-red in color. Adult specimens have deep-red color on much or most of the head.

Relevant scale counts: 19 midbody scale rows, scales are strongly keeled.

Similar Species: Red-necked Keelback only shows red coloration behind the head and has a less distinct checkered pattern rather than clear banding.
Speckle-bellied Keelback lacks red coloration on the head and has a light-colored lip that continues into a chevron joining at the neck.
Blue-necked Keelback has blue coloration in the area of the neck and a prominent dorsal stripe.

Range: Southern Thailand through peninsula Malaysia, Sumatra, and Borneo.

Habitat: Lowland forest habitats near swamps, marshes, and streams.

Place in the ecosystem: Feeds primarily on toads as well as frogs and lizards. Would be eaten by larger snakes, monitors, and birds of prey.

Danger to humans: It is not known to be venomous but other related species have dangerous bites so it should be treated with caution. Information on first aid for rear-fanged venomous snakes can be found here. The snake also has poison in the nuchal glands of the neck which may lead to illness if ingested.

Conservation status and threats: No threats are known and the range is fairly broad though the species is not commonly seen.

Interesting facts: The Orange-necked Keelback is one of several closely related snakes (including the Red-necked Keelback and Black-banded Keelback) which have poison-filled organs called “nuchal glands” in the skin of their neck. Incredibly, scientists have discovered that the poison in these glands is not manufactured by the snake, but actually comes from poison in the toads the snakes eat, which is somehow removed by the snake’s body and stored in the glands. When the snake is under attack, it exposes its neck to the attacker and the glands burst, spreading the toads’ poison over the surface of the skin and thereby making the snake both distasteful and potentially dangerous for the attacker.

References:
Ecology Asia: Orange-necked Keelback
IUCN Red List: Orange-lipped Keelback
Evolution of nuchal glands, unusual defensive organs of Asian natricine snakes
Reptiles of South-East Asia

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