The Family Anniellidae is represented by just one small genus from North America, Anniella. There has been some speculation about the relationship of these legless lizards to other lizard families, and indeed to the amphisbaenians and even snakes, but the latest thinking (as represented by the JCVI/TIGR database) places them in the Anguinomorpha, along with the Anguidae and Xenosauridae. Their saurian character is exemplified by their movable eyelids (lacking in snakes and amphisbaenians) and autotomous tail.
Common characteristics of the genus are: skull solidified (bones attached firmly to one another); lower jaw countersunk (as in amphisbaenians), with just a few conical teeth which widen at the base; bifid tongue, with papillae at the base; no external ear openings; no limbs, and only slight trace of pectoral girdle; smooth scales. Both species are livebearers. When compared, the snout of A. geronimensis is flatter in profile and less pointed from above, and the tail more pointed [Stebbins]. The coloration of both species is also somewhat different.
Stebbins also notes the negative impact of various human activities on populations of A. pulchra, including but not limited to the use of off-road vehicles in coastal dune areas.
| Scientific Name | Common Name | Distribution | Size | Notes |
| Anniella | ||||
| A. geronimensis | Geronimo Legless Lizard | Mexico (W coast of Baja California Norte and offshore island of San Geronimo) | 4-6/10-15cm, max 14cm SVL? | Coexists with A. pulchra in northern part of range. It is less catholic in its choice of habitat, preferring coastal dunes and sand flats stabilised by plant growth, and Grismer suggests that it is "highly and exclusively" adapted to the coastal dunes of the region. Scalation details: head scales large, platelike; 6-7 supralabials, of which 4th is largest and 1st completely encloses nostrils; 5-6 infralabials; mental large; 2 postmentals. Dorsal scalation: smooth, cycloid and imbricate, in 24-26 rows at midbody. Other: eye deeply sunk; 72-86 dorsal caudal scales. Coloration: dorsally silverish to light beige, with numerous (7-8) longitudinal narrow blackish lines flanking dull white stripes, and a narrow dark vertebral line; ventrally blackish [as per Stebbins] or greyish [as per Grismer]. Reproduction: 1-2 young born in summer. |
| A. pulchra | California Legless Lizard | California (USA) and Baja California (Mexico), including Los Coronados islands. | 4¼-7"/; max 10"/25cm? | Most often likened in appearance to a pencil due to its round shape and small diameter in ratio to length (no more than 9mm). Although the range of this species extends from the coast to the mountains at altitudes of up to 1,800m, the common factor throughout is the availability of loose sandy-loamy soil in which the lizard can burrow. A degree of moisture is essential. There is some similarity to the lifestyle of amphisbaenians: A. pulchra is usually a few centimetres underground, uses its shovel-shaped snout to dig (eyelids closed while so doing), and can seize prey from below. The body is moved forward by lateral thrusts. If there is enough foliage cover available the species is not averse to chasing prey (insects and spiders) above ground. Scalation details: head scales large, platelike; 6-7 supralabials, of which 4th is largest and 1st completely encloses nostrils; 5-6 infralabials; mental large; 2 postmentals. Smith notes for the nigra subspecies that the head scales may be fused in various ways. Dorsal scalation: smooth, cycloid and imbricate, in 28-30 rows at midbody (Smith cites for A. p. pulchra 30 at the head, 26 at midbody and 16 at the anus). Other: eye deeply sunk; 80-94 dorsal caudal scales. Coloration: see subspecies. Reproduction: 1-4 live young are born in Sept-Nov. |
| A. p. pulchra | Silvery Legless Lizard | As above | Coloration: dorsally yellowish-white, silvery or beige (in some areas, chocolate coloured individuals also occur) with three fine dark longitudinal stripes running between scale rows; ventrally yellow, with individuals from one area showing dark patches on underside. Regenerated tails are a uniform dark purplish brown. Tongue is lavender coloured. | |
| A. p. nigra | Black Legless Lizard | Restricted to small coastal area of Monterey Country, California | Coloration: dorsally black to black-brown, turning bluish shortly before molting; longitudinal stripes absent or very faint, or confined to tail; ventrally yellow. | |
Animal Life Encyclopedia Volume 6: Reptiles, Grzimek,1975.
A Field Guide to Western Reptiles and Amphibians, R Stebbins, Peterson Field Guides, Houghton Mifflin, Boston/New York 2003.
Amphibians and Reptiles of Baja California, Lee Grismer, University of California Press, 2002. Impressive guide to the herpetofauna of the region, includes both species of Anniella.
Handbook of Lizards: Lizards of the United States and Canada, Hobart M Smith, Cornell University, 1946 (1995 reprint).
I have not read the following, but it may be of interest and is certainly not expensive:
The California Legless Lizard (Anniella pulchra) and the Baja California Legless Lizard (Anniella geronimensis), M P Bettelheim, Walnut Creek 2005, 2nd edition.
The very fine site www.wildherps.com has a picture of A. pulchra.
The Moss Landing Marine Labs site gives some details of a project to relocate A. pulchra, include the use of transponders to track the lizards underground. Recommended.
Robert Sprackland has some useful information on A. geronimensis.
Back to Lizard Families | Lizards | Reptiles | Herpetology | Back to Home Page