Siren sphagnicola inhabits seepage areas in the eastern Gulf Coastal Plain of the United States.
Siren sphagnicola, an adult hypertrophic male with a partially regenerated tail. Image credit: Fedler et al., doi: 10.11646/zootaxa.5258.4.1.
Sirens are elongate, eel-like aquatic salamanders belonging to the family Sirenidae.
This family belongs to the order Caudata (salamanders) and currently comprises two genera, Siren and Pseudobranchus.
All living sirens possess external gills with comb-like filaments, lidless eyes, and laterally compressed tails with fin blades.
Additionally, they lack pelvic girdles and associated hindlimbs, a trait unique within salamanders.
Despite the abundance of Siren in some aquatic habitats, relatively little research has been conducted on interspecific differences in natural history and phylogeography of this genus.
“For approximately four decades, scientists have known of the existence of several undescribed species of Siren in the southeastern United States Coastal Plain,” said Dr. Matthew Fedler and his colleagues from the Fish and Wildlife Research Institute at the Florida Fish and Wildlife Conservation Commission.
“One of these species, Siren reticulata, was recently described, but a small, seepage-dwelling species has remained undescribed until now.”
“To resolve outstanding questions concerning the phylogeny of Siren, we collected sequence and morphometric data from specimens across the range of Siren.”
The newly-identified species, Siren sphagnicola (common name is the seepage siren),is around 20 cm in total length, making it the smallest known species in the Siren genus.
“Siren sphagnicola has typical Siren characteristics: external gills with three fimbriate gill stalks, three associated gill slits, four toes on the forelimbs, lack of pelvic girdle and hindlimbs, and a thin, pigment-bearing mucus layer that overlies the keratinized skin,” the researchers said.
“A combination of traits distinguishes it from other members of the genus: it has 30-33 costal grooves and a mouse gray base color with occasionally a light, grayish brown sheen on the dorsum.”
Siren sphagnicola ranges from the Florida Parishes of Louisiana eastward to the westernmost tributary creeks of Choctawhatchee Bay in the western Florida panhandle.
“Siren sphagnicola has a smaller geographic distribution than other Siren species,” the scientists said.
“Most specimens have been found in the Blackwater, Yellow, and Escambia/Conecuh river drainages of Florida and Alabama.”
“Elsewhere, its range is poorly known, but we believe it is restricted to the environs of sandy, seepage-fed creeks in the lower Gulf Coastal Plain as far west as the Florida Parishes of Louisiana.”
The discovery of Siren sphagnicola is reported in a paper in the journal Zootaxa.
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Matthew T. Fedler et al. 2023. Unraveling Siren (Caudata: Sirenidae) systematics and description of a small, seepage specialist. Zootaxa 5258 (4): 351-378; doi: 10.11646/zootaxa.5258.4.1
Source : Breaking Science News