American scientists have described three new species belonging to the Midas cichlid (Amphilophus citrinellum) species complex from Lake Apoyo in southwestern Nicaragua.
Publishing the descriptions in the latest issue of the Proceedings of the Biological Society of Washington, Jay Stauffer, Jeffrey McCrary and Kristin Black have named the three new species Amphilophus astorquii, A. chancho, and A. flaveolus.
Amphilophus astorquii, named after Ignacio Astorqui (a researcher working on the freshwater fishes of Nicaragua), is distinguished from other members of the genus in having a completely black head and caudal peduncle of breeding adults (vs. yellow or green in A. chancho and A. flaveolus) and distance of 41.1"47.9% standard length from the snout to the dorsal-fin origin (vs. 37.3"40.1 in A. zaliosus).
Amphilophus chancho is named after Spanish chancho (meaning pig), which is the local name for this species.
It differs from A. zaliosus in having a longer head (34.6"38.2% standard length vs. 32.5"34.0) and from A. astorquii in having a green-yellow (vs. black) head in breeding adults and a grey interorbital bar (absent in A. astorquii). Amphilophus chancho difers from A. flaveolus in having a shorter distance between the snout and the dorsal-fin origin (38.9"42.8% standard length vs. 41.6"47.5).
Amphilophus flaveolus is distinguished from A. zaliosus in having a greater distance between the posterior insertion of the dorsal fin to the posterior insertion of the anal fin (15.2"16.9% standard length vs. 13.7"15.5) and a greater distance between the anterior insertion of the dorsal fin to the insertion of the pelvic fin (41.5"46.1% standard length vs. 36.8"41.5). The differences with A. astorquii and A. chancho are as listed above. This species is named after its yellowish body colour (flaveolus means yellowish in Latin).
According to the authors, the three species are reproductively isolated, with A. astorquii and A. chancho nesting in dug or adapted preexisting holes in rocky areas at depths of 2"25 metres and A. astorquii tending to make and use smaller burrows while A. flaveolus nested in sandy or muddy substrates in water less than 2 metres deep. Furthermore, observations made while diving ...demonstrated that breeding of each species commonly occurs at distances of a few metres of the other respective taxa in Lake Apoyo.
For more information, see the paper: Stauffer, JR Jr., JK McCrary and KE Black (2008) Three new species of cichlid fishes (Teleostei: Cichlidae) from Lake Apoyo, Nicaragua. Proceedings of the Biological Society of Washington 121, pp. 117"129.