AmphibiaWeb - Sirenidae


(Translations may not be accurate.)


6 species in 2 genera

Commonly Called Sirens

Pseudobranchus axanthus
Photo by Todd Pierson
(Click for family gallery)

These are elongate, eel-like, small to large (750 mm snout-vent length) aquatic salamanders with external gills. The pelvic girdle and hind limbs are absent in all species but small forelimbs are present. Members of this family are paedomorphic, with adults retaining larval features such as gills, a lateral line system, and suction feeding (although they also possess moving jaws).

They are distributed in the southeastern United States and northern Mexico and usually are considered to be the sister group to all other living salamanders. Two genera belong to this family, Siren, and Pseudobranchus.

Written by AmphibiaWeb

Notable Family Characteristics

  • Aquatic
  • Inhabits both permanent and semi-permanent water bodies such as marshes, wetlands, ponds, canals, and lakes, preferring heavy vegetation
  • Paedamorphic adults
  • Generally nocturnal
  • Lays eggs
  • Some morphological characters for this group include: 1) non-pedicellate teeth; 2) maxillae reduced to tiny-free elements; 3) no premaxillary or maxillary teeth; 4) no pelvic girdle; 5) no hindlimbs, but small forelimbs.
  • Paedomorphic characteristics include: external gills, a lateral line system, and suction feeding
  • Distribution limited to southeastern USA and extreme northeastern Mexico in North America
Sirenidae Richness map

Cartography Credit: Zoe Yoo, UC Berkeley
Range maps sources: AmphibiaWeb, UC Berkeley, and IUCN RedList

Relevant Reference

Pough, F. H., R. M. Andrews, M. L. Crump, A. H. Savitzky, K. D. Wells, and M. C. Brandley. 2015. Herpetology. Fourth Edition. Massachusetts: Sinauer.

Vitt, L. J., and J. P. Caldwell. 2013. Herpetology. An Introductory Biology of Amphibians and Reptiles. Fourth Edition. Amsterdam: Elsevier.

Genus Pseudobranchus (2 species)
Pseudobranchus axanthus account photos no sound/video
Pseudobranchus striatus account photos no sound/video

Genus Siren (4 species)
Siren intermedia account photos no sound/video
Siren lacertina account photos no sound/video
Siren reticulata account photos no sound/video
Siren sphagnicola no account photos no sound/video

Citation: AmphibiaWeb: Information on amphibian biology and conservation. [web application]. Berkeley, California: AmphibiaWeb. Available: (Accessed:

AmphibiaWeb's policy on data use.