Siren lacertina
greater siren

Siren lacertina, the greater siren, occurs on the coastal plains of the southeastern United States, ranging from the District of Columbia south through Florida and the southern tip of Alabama.

Sirens are most common in ditches, lakes, ponds and other slow-moving fresh water. This nocturnal species spends most of the day hidden under debris or rocks, burrowed in mud or thick vegation. Young are often seen amid water-hyacinth roots. In times of drought they aestivate in mud burrows. Their skin glands secrete a moisture-sealing cocoon over their entire body, except the mouth.

Siren lacertina is an aquatic species with a stout, eel-like body. Adults are usually gray or olive, with dark spots on the head, back, and sides. The sides are lighter in color, and have many faint greenish-yellow dashes and blotches. These salamanders have external gills with 3 gill slits. They have front limbs with 4 toes. The tail is compressed with a rounded tip. Greater sirens can range from 49 to 97 cm in length. The common name "greater" comes from the fact that the other species in the genus, the Lesser Siren (Siren intermedia) measures less than 2 feet in total length, in contrast to the "greater" sirens which can exceed 3 feet in length. It's very difficult to distinguish small Greater Sirens from adult Lesser Sirens just by looking at them. Authorities suggest counting costal grooves, these are external grooves along the sides of the animal between the forelimbs and the vent which correspond roughly to the number of ribs. Greater sirens usually have more than 36 costal grooves whereas lesser sirens have less than 35 grooves.

The species is permanently aquatic and retains a larval form throughout life. They are are easily mistaken for eels. They spend most of their time in shallow, muddy-bottomed, weed choked waters. Greater sirens are nocturnal animals, and spend most of the day hidden in mud or under rocks and logs. The absence of hindlimbs and the relatively weak forelimbs make overland travel virtually impossible, for this reason sirens rarely emerge from water unless absolutely necessary. If caught, they may yelp, giving a call that sounds like a distant Green Treefrog (Hyla cinerea).

Sirens, like amphiumas, are effective predators of many small aquatic animals. They feed primarily on aquatic invertebrates, such as crustaceans and insect larvae. They also eat amphibian eggs and larvae, and small fish, and may consume aquatic plants.

This species has no negative effect on humans.

Sirens are mid-level predators in their habitats, and may help control insect and invertebrate populations.

Greater sirens do not seem to be currently threatened. The most serious threats to their populations are drainage of wetlands and the use of herbicides to clear aquatic vegetation.

'Siren' is Latin for 'mermaid' and 'lacertina' is Latin for 'little lizard'.