VENOMOUS SNAKES
OF NORTHERN YUCATAN

In our area people who machete bushes and weeds day after day and see more snakes than anyone are absolutely convinced that nearly every snake they encounter is deadly. Still, I've been telling them that during my several months of being in this area, after encountering lots of snakes, I've never seen a single venomous one. My saying this has accomplished one thing: People here are convinced that I know absolutely nothing about the local snakes.

According to Campbell's herp book, in arid, scrubby northwestern Yucatan we have these three venomous snake species:

1) Neotropical Rattlesnake, CROTALUS DURISSUS
2) Cantil, AGKISTRODON BILINEATUS
3) Variable Coral Snake, MICRURUS DIASTEMA

This is pretty close to the situation for much of the US Southeast: There's a rattlesnake, the Cantil belongs to the same genus as the Cottonmouth, and then there's the coral snake.

Eastward and southward from here in northwestern Yucatan, average yearly rainfall increases, vegetation becomes much lusher, and the landscape supports a greater species diversity. In northeastern Yucatan, which includes the Cancun area, a fourth venomous species occurs:

4) Barba Amarilla (Fer de Lance), BOTHROPS ASPER

Farther south in much rainier, high-forest areas other venomous snakes occur: The Jumping Pitviper; the Eyelash Palm-pitviper, and; the Rainforest Hognosed Pitviper.

Twice since I've been at San Juan good fusses have erupted over "coral snakes." One was curled beneath a potted plant on the veranda when Doņa Lupe the maid came watering. Both of these "corales" were Tropical Milksnakes, LAMPROPELTIS TRIANGULUM, admittedly looking very much like real coral snakes, but about as harmless and tame as a snake can be.

You can see how similar the are yourself. Our harmless milksnake is shown at http://www.cnah.org/detail.asp?id=179 while the dangerous Variable Coral Snake is at http://www.uta.edu/biology/campbell/guatemala/images/Micrurus_diastema.JPG