Excerpts from Jim Conrad's
Naturalist Newsletter

from the September 14, 2007 Newsletter issued from Sierra Gorda Biosphere Reserve, QUERÉTARO, MÉXICO
EXCITEMENT AT THE COMPOST BIN

Last Monday around noon I returned from the market to find several folks standing around the compost bin with body languages saying "Look at that!" When I got there Pancho told me they'd corner a "coralillo," a coral snake. In the Yucatan I got used to coral snakes being nocturnal, and nearly always in the past when people told me they had a coral snake it turned out to be a mimic species, so I didn't get too excited.

However, it turned out to be the real thing. Just to make sure my mind wasn't playing tricks I recited to myself the handy little verse:

Red on yellow,
Will kill a fellow...

And that's what it had. Below, you can see the red bands looking like they were applied atop wider yellow bands:

"Texas Coral Snake"
Querétaro's coral snakes used to be lumped with the Eastern Coral Snake, Micrurus fulvius, of the US Deep South. However, recent studies indicate that the coral snakes of northeastern Mexico are a different species, called the "Texas Coral Snake" by English speakers, though mostly it's found in Mexico. It is Micrurus tener

It was the Eastern Coral Snake, MICRURUS FULVIUS {see sidebar}, which is different from what we had in the Yucatan, which was the Variable Coral Snake, Micrurus diastema. Our Eastern Coral Snake was the same species found in the US Deep South and, as we see, through Texas into eastern and central Mexico. It's described as being "mostly diurnal," meaning that it comes out during the day. Often I've mentioned the advantages of being able to make assumptions about unknown species by extrapolating certain kinds of information already known about other species belonging to the same genus, but here's an example of how making such assumptions can sometimes be dangerous.

I don't particularly enjoy handling venomous snakes but it was clear that this one couldn't remain among the office buildings -- even though it provided a valuable service keeping the mouse population down around the compost heap. Therefore, with the snake's head pinned with a stick, I took him in my hand, snapped the above picture, put him into a two-liter Coke bottle with a cap on it, and gave him to Pancho to release in the mountains, which he did.

A funny thing about that picture: When I downloaded it into my computer, for an instant I thought I surely had the wrong picture, for the snake I remembered grabbing had certainly been at least three times longer and thicker than the teeny little thing shown in my hand...