One of several Malabar Pitvipers (Craspedocephalus malabaricus) we found on a very wet night in Karnataka, India. These vipers are numerous in the Western Ghats, where they are endemic.

One of several Malabar Pitvipers (Craspedocephalus malabaricus) we found on a very wet night in Karnataka, India. These vipers are numerous in the Western Ghats, where they are endemic.

Black-tailed rattlesnakes often have faint light bands on their tails, which can be confusing to observers who believe that they can only be solid black. On this one, it’s just barely visible, appearing as black and dark grey bands in a ratio similar to a Western Diamondback Rattlesnake. These are not hybrids, as is often suggested by people online. A more accurate way of viewing an all-black tail from this species: a banded tail with variable lighter bands, which often darken to be indistinguishable from the darker ones.
The rattle on this snake is also complete, which includes the full button that the snake was born with. The small, last segment, shows the rounded tip (prebutton), and notch that it gained with that first shed skin. This creates a full button, which it may rattle without making any sound. The subsequent sections (not “buttons,” as they are often mistakenly called) are left with each shed skin, which a young snake may do several times in a year. The shape of the rattle, too, indicates its age here. The strong taper, with each segment being larger than the previous, says that this snake is growing quickly. Once growth slows and nearly stops, each segment will be similar or identical in size to the previous, indicating an older snake.
This one was found near Phoenix a few years back.

A new rattlesnake for the National Park system. The newly minted Chiricahua National Park includes habitat for one of our state’s lesser-known venomous snakes.
Twin Spotted Rattlesnakes are small, high-elevation rattlesnakes that live in a handful of mountain ranges in the Sky Islands region of Arizona. Hikers may see them rarely, visiting the peaks and upper saddles of the Santa Rita, Huachuca, Pinaleno, and Chiricahua ranges.
In the Chiricahuca National Park, they may be found at the upper elevations, above 6,000′. Much of the park is lower than that, but the longer trails leading to Massai Point get into the right areas where one may be spotted.
They’re so small (usually under 2 feet long as adults) that most long-term visitors don’t even know they exist. They do rattle, but usually just silently slip off the trail or into the rocks. If a rattle does happen, it’s a quiet buzz that sounds more like an insect than a rattlesnake.
Twin-Spotted Rattlesnakes are protected in Arizona and should never be captured or killed.

Prival, D. B., Goode, M. J., Swann, D. E., Schwalbe, C. R., & Schroff, M. J. (2002). Natural history of a northern population of twin-spotted rattlesnakes, Crotalus pricei. Journal of Herpetology, 36(4), 598–607. https://doi.org/10.1670/0022-1511(2002)036[0598:NHOANP]2.0.CO;2
One of several White-Lipped Pit Vipers (Trimeresurus albolabris) we saw on a hike in the hills above Hong Kong several years back.

This is one of a couple of Arizona Black Rattlesnakes (Crotalus cerberus) we found in the Hualapai Mountains near the western extent of their range. These snakes in this area can be highly variable, ranging in appearance from the typical black rattlesnake look to lighter, blotchy patterns that hint at possible influence by others in the Western Rattlesnake clade. This one is a bit of both.

A young Baja California Rattlesnake in Baja California Norte, Mexico several years ago. These small rattlesnakes are common throughout most of the peninsula. They inhabit about every type of habitat imaginable, from sandy beaches to nearly sheer cliffs, and everything in between.

Diet of Crotalus enyo (Serpentes: Viperidae) from the Baja California Cape Region, Mexico
Carbajal-Márquez, R. A., Arnaud, G., Martins, M., & Quintero-Díaz, G. E. (2016). Acta Zoológica Mexicana, 32(1), 45–48.
Diet of the Baja California Rattlesnake, Crotalus enyo (Viperidae)
Taylor, E. N. (2001). Copeia, 2001(2), 553–555.
A Western Diamondback Rattlesnake sitting outside of its den in late November. Days later, it disappeared into the rock pile to hibernate.
In Maricopa County, ingress to their selected overwintering sites typically concludes by about the second week of November, unlike Spring emergence, which is a longer process of basking and social behavior that puts them on the surface every day for weeks or more, getting to the den itself is typically less active.
Females and young snakes tend to disappear immediately, likely to avoid burning off the moisture and energy stored throughout the year. Males, especially the larger and older individuals, may continue to bask and conduct social dominance behavior for awhile, before again disappearing to stable, hidden conditions.
For homeowners, this means that the locations where they may be found change dramatically in nature. Unlike pass-through rattlesnake encounters from the Fall, a snake found from November through February is a long-term resident. This also means that these situations are also very fixable. The stable environmental conditions offered by something like an unused wood pile, access under an old shed, or other easy thermostable situation, are very useful. Once the snake is relocated, the homeowner should receive the information about the situation needed to solve the real issue.

I spotted this Southwestern Speckled Rattlesnake standing out amongst dark basalt on a crumbly hillside in the Maricopa Mountains a couple of years back. It’s only the second I’d seen in the range, with the first not resulting in a photograph worth saving.

Arizona has a state reptile that most people will never see, and relatively few know it exists. The Arizona Ridgenosed Rattlesnake.
An Arizona Ridgenosed Rattlesnake from the southeastern corner of Arizona. They’re small rattlesnakes, with most that I’ve encountered being less than two feet long. They’re not in the desert, but live in higher elevation oak forests and grassy hills. Even in areas where they are abundant, life-long locals usually greet questions about them with something that sounds like “a what?”
Here’s one we found awhile back in Cochise County, Arizona.

We found this relatively large Central American Eyelash Viper (Bothriechis nigroadspersus) on a family trip to Costa Rica a few years ago. Unlike many of the vipers I work with back home, this one just wanted to escape upward, showing off those supraocular “eyelash” scales.
