The Mystery of the South Florida Rainbow Snake

(Adapted from a previous essay by the author)

A great many people live under a false pretense… To them, the world has been completely explored, recorded, prodded, analyzed, exploited, raped, and exported in clean packaging; arriving comfortably in their houses in the form of T.V., the internet, or magazines. But this is certainly not fact, for the world is a wide and untamed place, full of mystery – a place where any answers crack open a Pandora’s box of more questions, and any semblance of understanding and control is regularly interrupted with exclamations of “Where did that come from?!” In the moon glow of this reality slithers a serpent known only by a name and a few observations of long dead explorers: The South Florida rainbow snake (Farancia erytrogramma seminola).

It shares the genus Farancia with one other species – the Mudsnake, Farancia abacura. This genus is distinguished by a primarily aquatic lifestyle, similar body shape and structure, and a spine at the end of the tail. The South Florida Rainbow Snake’s specific name, erytrogramma,  is actually a misspelling of the latin erythrogramma. The seminola subspecies was described by Wilfred Neill in 1952. This subspecies is of particular interest because its rarity – only three specimens have ever been found, and those three were found between 1949 and 1952, placing it firmly as a contender for the rarest snake in North America.

What is equally fascinating is that the seminola subspecies occurs over 250 miles disjunct from any other populations of rainbow snakes. Two of the three specimens, according to Wilfred Neill; “…were found in water of a sizeable stream at night,” stating its location as “Fisheating Creek, about 1 mile South of Palmdale, September 13, 1952.” (Neill, 270) Other than these two, only one other specimen was known, from the collection of herpetological legend Ross Allen, preserved and jarred – the locality given by the jar label was ‘Glades County, near Lake Okeechobee, July 24, 1949,’ which is likely synonymous to the mouth of Fisheating Creek.

The South Florida rainbow snake, like all of the other members of the genus Farancia, is non-aggressive – in fact, the pinnacle of their protest to handling is not biting, but jabbing (unpainfully so) with their tail. Because of this defenselessness, rainbow snakes are predated upon by a number of other animals. These animals include the ‘usual suspects’ for snake predation: raccoons, opossums, and hawks. Additionally, species such as the Eastern Indigo snake (Drymarchon couperi) have been seen eating F. e. erytrogramma. Indigo snakes are not uncommon in Glades County so it is likely that they have made a meal from F. e. seminola from time to time. in the distant past.

Rainbow snakes are a non-venomous species, and a long and heavy bodied animal; the largest of the F. e. seminola individuals was 131 centimeters long (4 ft, 3 inches,) though F. e. erytrogramma has a record size of 168 centimeters (5′ 6″.) Rainbow snakes are so called for a rainbow-like iridescence which is very pronounced and brilliant in the sun. They have one dorsal and two lateral red lines that run down the length of their body, though the dorsal line is reduced in F. e. seminola. All members of the genus Farancia have a hardened spine at the end of their tail, which is often used to control their prey while eating. Rainbow snakes are smooth scaled, with a divided anal plate – they are a nocturnal species most frequently seen during the months of March, June and October.

Fisheating Creek (https://fieldventures.wordpress.com/2011/09/09/area-profile-fisheating-creek-wma/) itself is a large stream that snakes from Lake Okeechobee through Glades county and west to the Gulf of Mexico. In dry years it is often no more than a cluster of ponds and lakes where there once was a creek. The area in and around Fisheating Creek is one of the most pristine remaining in Florida –  rare species such as Indigo snakes (Drymarchon couperi) and Eastern Diamonback Rattlesnakes (Crotalus adamanteus) are relatively commonplace, and even road signs in the area tout caution at the presence of Florida black bears (Ursus americanus floridanus).

This pristine habitat is likely the combination of the relative lack of large settlements nearby (The closest towns are small ones like Venus, Palmdale, with the nearest settlement of any size are Labelle to the south and Sebring and Lake Placid to the north – and even these are small towns,) and the fact that much of Fisheating Creek was blocked from access by the Lykes Brothers (of hotdog fame) for many years.

Rainbow snakes are most often seen by researchers in the water by night, being revealed in floating mats of vegetation by a small head periscoping out of the water, in fact, this is how Neill’s two individuals were found. They have also been found on roads on warm nights shortly after dark, and are also sometimes seen in the knees and roots of cypress trees in the early morning. Despite their occasional collection on land, rainbow snakes are primarily aquatic – even more so than other aquatic species of the genus’s Nerodia.

Unlike the sympatric mudsnakes, which prefer stagnate, turbid and isolated bodies of water and swamps, rainbow snakes prefer unpolluted, clear, calcareous moving water systems – note that this preference may be due to their prey, the American Eel (Anguilla rostrata). According to Neill, locals would often say of rainbow snakes “Ever’ time ya see one, he got an eel tail a’hangin’ out his mouth.”  (Neill, 274.) This observation is surprisingly accurate due to the typical feeding behavior of F. erytrogramma – They will often capture an eel under water and subsequently finish the meal among cypress roots or in bushes along their section of a stream, at times seen resting with the eel’s posterior hanging from the snake’s mouth. In fact, the best time to see the South Florida rainbow snake may very well be in the morning, when it is finishing its meal.

Because their diet consists almost entirely of eel, manmade structures such as dams and locks, which heavily modify the water flow, can often decimate a rainbow snake population. With this is mind, it is possible that rainbow snake populations existed in other areas in the past (the Kissimmee River, etc.) and may have been decimated by ‘wetlands reclamation’ and water flow modification.

Despite speculation of another time when Rainbow snakes might have been “common,” some species, it seems, are naturally rare or seldom encountered by man. An example of this is the South Florida mole kingsnake (Lampropeltis calligaster occipitolineata) – this species was not discovered until even later than the rainbow snake – it was described in 1987, and since then under 100 specimens have been encountered alive in the wild. The South Florida rainbow snake likely falls into the same category as the South Florida mole kingsnake. A likely explanation for the natural rarity of these two species (and a number of other South Floridian animal species, including at least two other snake species: Tantilla oolitica and the Lake Placid population of Virginia valeriae,) lies within Florida’s geologic history.

Florida consists of a long history of fluctuating water levels, and quite recently in Florida’s history the peninsula was under water, save for a couple elevated dunes/sand bars; the largest of which was the Lake Wales Ridge – it stretched through central Florida and south through what is currently Sebring and dipped off a bit south of present day Lake Placid, Florida. This ancient island served as a Noah’s ark for many species, which experienced divergent evolution over time from their mainland counterparts – when the waters receded the animals spread out slightly, but most South Florida endemics remain relatively close to their original ‘island’.

Though the rainbow snake seems to be uncommon even without man’s meddling, it would be highly profitable, scientifically, to research and rediscover the species. Several attempts have been made to locate more specimens in recent history by myself and others, but have come to naught – it is difficult to find even a F. e. erytrogramma in its native range, much less seminola. During August of 2009, I trapped and searched with some colleagues for the South Florida Rainbow snake to no avail. Recreational ‘field herpers’ too have tried within the past couple of years to come across one, but they have also failed.

In light of such ‘slim pickings,’ it is tempting to label this animal as outright extinct, but it is of the opinion of the author that it is very likely that this species does, in fact, persist to the current time, but the isolation of its locale and naturally few numbers make it rare to encounter. Either way, for now it remains but a mystery, open only to speculation – and dreaming.

-Neill, W. T., 1964, Taxonomy, Natural History and Zoogeography of the Rainbow Snake, Farancia erytrogramma, The American Midland Naturalist, V. 71, p. 257.