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| The Long Nosed Whipsnake, Ahaetulla nasuta (Lacepede, 1789). Photographed in the Khorat Basin, central Thailand. Adult maximum size approaches, if not exceeds, 2 m. It is an extremely slender diurnal snake that feeds mostly on lizards. I have found this snake in forest-edge habitats as well as urban settings. It lives on the Chulalongkorn University campus in downtown Bangkok. Coloration and pattern are highly variable with green, brown, and yellow specimens being common. Click on the photo for more Asian colubrids. |
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| The Glossy Snake, Arizona elegans Kennicott, 1859. Photographed near Tucson, Arizona. This specimen is referable to the subspecies A. e. noctivaga. Click on the photo for more North American colubrids. |
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| Chironius carinatus (Linnaeus, 1758). Photographed in the Arima Valley, Trinidad. It inhabits lowlands from Costa Rica to Ecuador and the Guianas and Brazil. It also occurs on Trinidad. A diurnal snake, it can be found in forests, forest edges, and disturbed areas where it hunts for frogs. This snake may crinkle its body to resemble a liana to escape visually oriented predators. Click on the photo for more Central and South America colubrids. |
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| The Common Snakes, family Colubridae, has previously contained more than 70% of the world's snakes. These snakes have had their anatomy remodeled so many times by evolution that their relationships to each other have been obscured to science. With the ability to sequence DNA the relationships of these animals has become clearer. Here I am following Vidal et al.'s (2007 C. R. Biologies 330:182-187) reorganization of these snakes. Some clades have been removed and placed in their own families, in the past many of these were considered subfamilies. The Colubridae is now a monophyletic (one ancestor) clade. Colubridae now contains about 95 genera and about 1750 species. They occur on all continents where snakes can be found and on many islands. The family is divided into three subfamilies: Colubrinae, Calamariinae, and Grayiinae. Many authors have applied the name "Harmless Snakes" to these animals, with the idea that they are harmless to humans. This is an over-simplification. Some of these snakes pose a threat to human health because of the toxic molecules they produce in their oral glands. And in fact, it is likely that more of these snakes produce oral toxins than do not. However, most pose no health threat to humans. |
