Genus: Urotheca

Posted on April 9, 2011 by Tim 4 Comments

So, the first entry will be about a cool group of snakes in the genus Urotheca. These snakes are usually smallish, up to foot-long pencil-sized, (typical) colubrids with long tails and found from southern Mexico into northwest South America. They are usually dark in color (brownish to black bodies) and usually have stripes running the length of their bodies. Two of the 9 or 10 species are coral snake mimics and have bands as opposed to stripes. Urotheca are closely related to the leaf litter snakes in the genus Rhadinea. Urotheca are relatively unique in the snake realm in their ability to drop their tails as a predator avoidance response – similar to some lizards. Savage reports that unlike lizards, the tails require some force to break and the breaks occur between vertebrae. Also, the tails are not regrown at all. The broken tail tips are autonomous and thrash about which can confuse predators or distract herpetologists not paying attention. Not a lot is known about these animals and they seem to undergo a frequent taxonomic shuffling. It appears they mostly feed on small amphibians.

 

I was first introduced to this genus in 2001 with a lone specimen of Urotheca decipiens. My photography was relatively poor back then so my few frames I have are not impressive. In 2006 Twan and I caught another U. decipiens, of which I managed to get a few acceptable frames of this stunning animal with a bright orange head.

 

This 2006 photo of my second Urotheca decipiens shows the spectacular orange head/collar, black body, and characteristic white lateral and dorsolateral stripes.

 

I didn’t give the genus much thought until 2009 when herp student extraordinaire, Meagan Murray found a little snake that a dozen people missed in the middle of the trail (including yours truly). I recognized the gestalt as Urotheca but it lacked the orange head and white belly that I knew from U. decipiens. With the help of Savage’s text I learned about U. pachyura – a new record for Rara Avis and the snake find of that year’s project. For a while U. decipiens was considered a subspecies of U. pachyura. There is a strong similarity and coupled with individual variation one could see the confusion. But looking at the photos of these individuals you can also see their uniqueness.

 

In 2009 Meagan Murray found this first record of Urotheca pachyura at Rara Avis. It has a similarly, albeit less intense, head and collar color of U. decipiens, and the remnants of a white lateral stripe, but the ground color is greenish with a yellowish venter.

Pages: 1 2 3