Note the yellow interstitial skin of this forest racer.
The genus Dendrophidion contains about 15 species of big-eyed, diurnal, alert snakes, all of racerlike slenderness and speed. The overall distribution of the genus is from southern Mexico to Bolivia. The Tawny (aka Olive) Forest Racer, Dendrophidion dendrophis, was a common and welcome species at our camps in Amazonian Peru.

Although of subdued color this is a pretty snake. The ground color is lightest anteriorly and darkens progressively towards the tail. A series of 50+ narrow, dark-edged, light bands or dark bands with light lateral spots, begins on the nape, and continues to tailtip. These are best defined on young snake and may be obscure on old adults. The Interstitial skin (the skin between the scales) and the belly are yellow, paling anteriorly. Each eye is shaded by an enlarged, flat, outward projecting, supraocular scale. The eyes of juveniles appear proportionately larger than those of the big-eyed adults.

Adult size of this oviparous snake is 3 to 4 feet. This is a frog-eating species.

These racers are most often seen on or near the ground, but they can climb well and often sleep in shrubs or trees 5 to 8 feet above the ground.

The fact that this snake (as a matter of fact, all snakes in this genus) readily autotomizes the tail if grasped by this terminal appendage explains why many forest racers seen have a truncated appearance. The tail is readily lost but does not regenerate.

This is a typically colored hatchling Banded Calico Snake
Varying by researching authority, the genus Oxyrhopus contains 12 or more, largely nocturnal, neotropical (central and northern South America, including Trinidad and Tobago) snake species that vary widely in color. Some are primarily red others are primarily black, some bear bands of contrasting colors, others, except for the head that often contrasts with the body color, are largely unicolored.

In my opinion, one of the prettiest is the Banded Calico Snake. Other frequently heard common names include False Coral Snake and Forest Flame Snake.

Long known as Oxyrhopus petola, Jay Savage has recently suggested that its proper name is O. petolarius, and that this contains 3 subspecies, including the one with which I am most familiar, O. petolarius petola.

Over the years we have gotten very used to visits from this Calico Snake at the preserves where we stay. We not only happen across adults on the trails and juveniles in trailside shrubbery, but the adults range widely and often stray into our campsites.

Hatchlings and juveniles of this yard long, oviparous, snake are banded white and black, most young adults are banded with bright red (sometimes white) and black, and the red bands old examples often darken until the entire snake looks sooty.

Although these snakes were initially considered rear-fanged colubrines, they have now been reclassified as a Dipsadine genus. The venom seems especially virulent against lizards and amphibians on which calico snakes primarily prey. Small rodents and birds are also prey items.

I have found this snake reluctant to bite.

Juvenile Common Bird Snakes are strongly patterned and highly arboreal.
A common snake in Amazonian Peru, the actual range of this feisty snake is from Mexico through most of northern South America. Both the genus and the species/subspecies names for this snake are currently in flux. Some refer to it as Pseustes poecilonotus, some as Phrynonax polylepis, and others simply refer to it, as I have, as the Common Bird Snake. At the moment I’ll also use the long-standing name of Pseustes poecilonotus for its scientific designation. The snake simply doesn’t care what you call it but is apt to display resentment if you approach it too closely.

We have found many of these snakes, but have never yet found one that was happy to see us. Neck distention, similar to that of the better known Spilotes, is a defensive ploy that may be used before, during, or after the snake has struck at you. Bird snakes are nonvenomous. Juveniles are strongly patterned and quite arboreal often being found at face level or above in trailside trees. Adults are more often found resting at night while coiled atop fallen trunks or simply on the trail.

The common name comes, of course, from this snake’s fondness for birds and their eggs. Small mammals, lizards, frogs, and insects are also eaten.

Coastal eastern Black Rat Snakes are often jet black dorsally.
Long in the herpetocultural shadows of more brightly colored rat snakes, it now seems that much interest is being channeled to the big Black Rat Snake, Pantherophis obsoletus obsoletus. Although I’m surely missing some, genetic aberrancies such as white-sided, albino, lavender, rusty, brindle, and calico, have been developed. But let’s talk about the normal rather than the aberrances here.

The Black Rat Snake, a big dark colored constrictor, has an immense range in eastern USA. Using state abbreviations, it may be found from New England’s Lake Champlain to neGA, then seMN to cKS and cLA. Habitats include stone walls, woodlands, pasture edges, deserted buildings and other such structures.

It, like its several subspecies, is adult at 5 to 6 feet in length. Occasional examples have exceeded 8 feet in length. With a record length of 101 inches it is one of the 5 longest snakes in the USA.

When adult this is a large, primarily black, harmless, but often feisty, semi-arboreal snake. Black above, traces of darker blotches may be seen, and if the snake is a hatchling/juvenile, or distended with a meal or gravid. Patches of white, gray, or orange interstitial skin (the skin between the scales) may also show. Dorsal patterns are also more apt to be seen where this snake nears the ranges of the Gray Rat Snake and Texas Rat Snake. The belly is white with irregular blotches of black.

Typically hatchlings are gray with black saddles. Various colors, especially a dark olive green, may show at areas where this snake intergrades with the yellow rat snake. Rodents, birds, and lizards are the preferred prey items of this powerful constrictor.

Rat snakes, as a group, will hiss if frightened and will often vibrate the tail. This latter, if in dried grass or leaves, will make a whirring sound that is similar to the noise of a rattlesnake’s rattle.

Know the difference before you approach.

This terrestrial snake is easily differentiated form its rough-scaled cousin by the lack of keels on the scales.
I know I’ve talked earlier about this little snake, but I would like now to bring to the forefront the fact that the Smooth Green Snake, Opheodrys vernalis, is in trouble.

Dorsally, this small (adult at 15 to 24 inches), smooth scaled, slender, and beautiful snake is leaf green (grayish or yellowish in some small populations and duller immediately after hatching, immediately before shedding or after death when it is bluish). Ventrally it is yellow, white, or pale green belly. It is predominantly terrestrial and was once common to abundant in open grassy areas such as unkempt urban fields, meadows, pastures, and edge habitats. An oviparous species, eggs have a curiously shortened incubation period, hatching in from 4 to 24 days. Hatchlings are duller than adults.

In the east this is a snake of habitats that vary from coastal and other lowlands to montane meadows. The few western populations are found at high elevations. Overall, this snake is considered a boreal species. The northernmost populations are found in Canada’s Maritime Provinces westward to southern Saskatchewan. The southernmost populations were in nw Virginia and s Illinois. Westward of this unusual range there are 25 or 30 small disjunct populations known as far as e WY, ne UT, and the grasslands of e TX (this latter now thought to be extirpated). A population has even been documented in w Chihuahua, MX.

For reasons that have not yet risen above the speculative stage, entire populations of the smooth green snake have now disappeared, and in those now existing, the snake is becoming increasingly rare. With no smooth green snakes having been found in TX in recent years, this population is of special interest. It is wondered by some researchers whether those once found in TX might have been introduced rather than of natural occurrence.

So, why the overall smooth green snake reductions? Is it because of habitat modifications? Probably not. There are still a lot of grasslands, some very remote, throughout this snake’s one-time range.

Could it be dietary. Afterall, this is an insectivorous species, crickets, caterpillars, and an occasional spider being among its favorite prey items. The prevalent use of a wide variety of insecticides has reduced insect populations, this snake’s potential prey.

Is it due to toxic effect from the insecticides themselves? Possibly.

Whichever and whatever it is a problem that we must soon get a handle on lest there be no smooth green snakes left to concern ourselves with.