A. Side and dorsal views of tail.
B. Horizontal section of head, showing Harderian gland and eye.
C. Horizontal section through right eye.
D. Horizontal section of left eye, showing pigmentation and lens.
E. Distal part of eye, showing layers of retina.
F. Proximal part of another eye, showing cyst.
Rhineura floridana, known as the North American worm lizard, Florida worm lizard, or thunderworm, is the only member of the monotypic genus Rhineura. This species is found primarily in Florida but has been recorded in Lanier County, Georgia. No subspecies are currently recognized.
Rhineura floridana varies in length from 18–30 cm (7–12 inches). The head has a shovel-like snout that projects forward past the lower jaws, which is used for burrowing. The eyes are highly reduced and not visible externally. The limbs are absent and, as in other Amphisbaenia, the body is covered by scales arranged in rings giving the animal a worm-like appearance.
They are burrowers, preferring a soil sand or leaf mold substrate, and spending most of their time underground where they are safe from predators. They surface only when plowing or heavy rain forces them to evacuate their burrows. Because of the latter, they are sometimes called thunderworms. When disturbed, they retreat into their burrows tail-first. Their diets include insects and earthworms, but they are opportunistic feeders and will eat almost any invertebrate small enough to catch. Reproduction is by laying eggs (oviparous).
This species is classified as Least Concern on the IUCN Red List of Threatened Species (v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because it is unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend is stable. Year assessed: 2007.
- "Rhineuridae". Integrated Taxonomic Information System. Retrieved 19 August 2007.
- "Rhineura floridana". Integrated Taxonomic Information System. Retrieved 19 August 2007.
- "Rhineura". Integrated Taxonomic Information System. Retrieved 19 August 2007.
- 2001 Categories & Criteria (version 3.1) at the IUCN Red List. Accessed 6 September 2008.
- Rhineura floridana at the IUCN Red List. Accessed 6 September 2008.