Excerpts from Jim Conrad's
Naturalist Newsletter

from the November 26, 2017 Newsletter issued from Rancho Regenesis in the woods ±4kms west of Ek Balam Ruins; elevation ~40m (~130 ft), N20.876°, W88.170°; north-central Yucatán, MÉXICO
A BIG, PRICKLY AUTOMERIS CATERPILLAR

On the rocky forest trail leading into the rancho early one morning I came upon a large, green caterpillar bristling with what looked like stinging hairs. Below, you can see it being held gingerly in my hands:

AUTOMERIS cf METZLI

Sadly, when I turned the caterpillar so I could photograph the head, the head had been smashed, and the caterpillar was dead. I'd thought he'd just been stunned by the morning's chill. Still, I got a shot of patterns along its side, and of the stinging hairs, shown below:

AUTOMERIS cf METZLI, trichomes and body pattern

The large size, the hair structure and the greenness all reminded me of a caterpillar we've seen at Chichén Itzá, which, with the help of an expert, was identified as possibly Automeris maloneyi. The caterpillar in the above photos surely belongs to the same genus, and the name that volunteer identifier Bea in Ontario came up with fit the bill. Bea says it might be AUTOMERIS METZLI, and I find that that species should be in our area. Its distribution is given as from Mexico through Central America to northern South America.

Despite the species occurring over such a large area, not much more information about it is available. I'm parking the pictures here, hoping that eventually someone studying the genus will be glad to see them, and have documentation that Automeris metzli can be found here in November.