A new species of etropline cichlid from northeastern Madgascar has been described by cichlid experts John Sparks and Robert Schelly of the American Museum of Natural History in a recent issue of the journal Zootaxa.
The new species is named Paretroplus loisellei after biologist Paul Loiselle for his efforts to document, preserve, and educate the public regarding Madagascar’s unique and severely threatened freshwater fishes.
Paretroplus loisellei is a member of the P. damii clade, which includes P. damii, P. nourissati (pictured above), P. tsimoly, P. lamenabe, and an unnamed species the authors refer to as P. n. sp. "anjingo" as its other members.
This group of Paretroplus differs from all other congeners in having the following characters:
- the scales on the sides of the body have a thin and unossified rear portion;
- both the dorsal and anal fins possess multiple discrete rows of scales that extend onto the fins;
- the chest scales are markedly reduced in size and highly embedded, with the belly scales along the ventral midline exhibiting the greatest reduction in size;
- multiple rows of small scales on the flanks on top of the area around the pelvic fins and anus;
- a triangular, black or dark grey patch at the base of the pectoral fin.
The new species differs from all congeners except P. damii in having a triangular, black patch at the base of the pectoral fin in combination with the lack of prominent vertical bars on the flank.
Paretroplus loisellei is distinguished from P. damii by the presence of an almost straight (vs. rounded) throat region in lateral view, horizontally-oriented (vs. strongly oblique) jaws, enlarged and fleshy (vs. thin) lips), an elongate and curved (vs. short and straight) snout that imparts a beaked appearance, the enlarged teeth in the middle of the upper jaw with distinct, sharp (vs. poorly developed and rounded) lateral cusps, and a bright golden (vs. brick red) breeding colour.
The new species is known from the middle reaches of the eastward-draining Mahanara River, located to the north of Sambava near the town of Antsirabe-Nord, northeastern Madagascar.
For more information, see the paper: Sparks, JS and RC Schelly (2011) A new species of Paretroplus (Teleostei: Cichlidae: Etroplinae) from northeastern Madagascar, with a phylogeny and revised diagnosis for the P. damii clade. Zootaxa 2768, pp. 55–68.