A new species of killifish with a mode of reproduction similar to that of livebearers has been described from Brazil.
Campellolebias intermedius, which was discovered in Sao Paulo, Brazil, has just been described by killifish authority Wilson Costa of the Federal University of Rio de Janeiro.
Costa's paper, which has recently been published in the systematics journal Zootaxa, examines the taxonomy and phylogenetics of the Campellolebias genus of rivulid killies in a short revision of the group.
Like the other species in the genus, C. intermedius, is unusual in that it has a structure similar to the gonopodium of livebearing toothcarps, which is used to inseminate the female with sperm.
Known as the pseudogonopodium, the structure is formed on the anterior tip of the anal fin of males.
Costa says that the pseudogonopodium, a derived caudal skeleton, and unique colour and courtship patterns diagnose the killifish group.
The revision lists four species in the Campellolebias genus, all of which are endemic to the southern coastal plains of Brazil.
C. dorsimaculatus and C. intermedius are known from the Rio Ribeira de Iguape basin in Sao Paulo; C. chrysolineatus was discovered in northern Santa Catarina, while C. brucei was found in southern Santa Catarina.
At least one of the species, C. brucei, is considered endangered and is listed on the current IUCN Redlist of fishes.
For more details on the tropical fish see the paper: Costa, WJEM (2006) - Taxonomy and phylogenetic relationships among species of the
seasonal, internally inseminating, South American killifish genus
Campellolebias (Teleostei: Cyprinodontiformes: Rivulidae), with the description of a new species. Zootaxa 1227: 31-55 (2006).