"Love means loving the unlovable - or it is no virtue at all."

    Heretics

    Gilbert Keith Chesterton (1874-1936)

    Catholic apologist, essayist, novelist, and poet

Puerto Rican many-ringed amphisbaena, Amphisbaena bakeri. Maricao State Forest, western Puerto Rico.

Lurkers Underground

ORDER AMPHISBAENIA

    Amphisbaenians, sometimes called "worm lizards" (perhaps a name better reserved for the gymnophthalmids - see below) were until recently considered to be legless lizards. However, they are now placed their own taxonomic order, Amphisbaenia, apart from lizards and snakes. These are indeed weird, fascinating animals.

    They might be distantly related to teiids (tegus, whiptails, ameivas, etc.). Their generic name comes from the Greek, "that which walks in two directions", for their capacity to move equally forward and backward both inside their subterranean burrows as well as above ground. The name also makes allusion to the fact that it is quite difficult at first glance to tell which end of the animal is which, since the stubby tail resembles the head.

At first glance, the head and tail of an amphisbaenid look alike.

First photograph: Virgin Island's amphisbaena, Amphisbaena fenestrata. Crown Mountain, central Saint Thomas, United States Virgin Islands.

Second photograph: Puerto Rican xeric amphisbaena, Amphisbaena xera. Guanica State Forest, south-western Puerto Rico.

    As an adaptation to a burrowing life, the bones of their skulls and jaws are heavy, solid, and partially fused together. They use their heads for shoveling soil and tunneling under rocks, roots, and fallen logs. They are seldom seen above ground, and even then only at night or when torrential rains flood their lairs. Like snakes, they are mostly deaf to airborne sounds, but are highly sensitive to vibrations in the substrate, and their protractible bifid tongues help them enhance their strong sense of smell.

    The members of the Mexican family Bipedidae is unique among all extant reptiles in having only forelegs.

A Virgin Islands amphisbaena, Amphisbaena fenestrata, uses its head as a shovel in order to burrow underground.

Crown Mountain, central Saint Thomas, United States Virgin Islands.

Family Amphisbaenidae: Amphisbaenas

    All West Indian members of this order belong to the family Amphisbaenidae. The group is present in South America, southern North America, Africa, Europe, and in the West Indies they are found in the Greater Antillean island banks, except for Jamaica's. Two genera are present in this region. Cadea (two species) is found only in Cuba, while Amphisbaena is present in the Cuban (three species), Hispaniolan (seven species), and Puerto Rican (five species) island banks. It is probable that more species await discovery.

Cuban spotted amphisbaena, Cadea blanoides. Viñales, Pinar del Rio, north-western Cuba.

(Photograph courtesy or Dr. S. Balir Hedges).

Hispaniolan dwarf amphisbaena, Amphisbaena manni. Bani, south-western Dominican Republic Hispaniola.

(Photographs courtesy of Mr. Miguel Angel Landestoy).

    As happens with the blind burrowing snakes like Typhlops and Leptotyphlops, the diverse species of amphisbaenas are very difficult to tell apart at first glance. They all look extremely similar to one another, and one often has to look closely at their head squamation or count body annuli to be identified.

Puerto Rican xeric amphisbaena, Amphisbaena xera. Guanica State Forest, south-western Puerto Rico.

This species is limited in its distribution to the dry, south-western region of the island.

    Amphisbaenas are small but fierce predators capable of biting off pieces from any small animal that crosses their path, and then swallowing them with the help of their short and muscular tongues. They occasionally eat carrion, as well. Many don't hesitate to bite when handled and, although indeed their teeth are very sharp and their jaw muscles are enormously strong for their size, none except the largest species can inflict any serious pain on a human hand. All the same, even rather small species can draw some blood, delivering quite a pinch by fastening to a finger with bulldog-like tenacity, and then twisting their bodies around, seemingly with every intention of ripping off as big a chunk of flesh as possible.

    With their elongated but stout bodies surrounded by rings of squarish scales, their inconspicuous eyes, and their usually gray, cream, or pink colors, these strange reptiles resemble fat earthworms. Their vestigial eyes are useless except to distinguish between light and dark, but can nonetheless be noticed under the translucent skin of their heads.