Related FAQs:  Poeciliids (Mollies, Platies, Guppies, Swords), Goodeids,  Killifishes,  Articles on Livebearing Toothed Carps: Poeciliids (Mollies, Platies, Guppies, Swords), Goodeids, Anablepids (Four-Eyes),  Articles on Egg-Laying Toothed Carps: Killifishes: Part 1 by Dr. Robert J. Goldstein, Killifishes, Part II- The Nothobranchius Family  by Robert J. Goldstein, Ph.D, Aphanius: European Killifish for Ambitious Aquarists by Matt Ford, /A Diversity of Aquatic Life  Order Cyprinodontiformes (Microcyprini)

Sabrina at home in Stanford, at the Nothobranchius rearing facility

Nelson asserts the monophyly of this group on the basis of their:

1) Symmetrical caudal fins, supported internally by one epural (bone).

2) Presence of first pleural rib on the second vertebrate (rather than third).

3) Presence of the pectoral girdle (low), with the postcleithrum bone scale-like.

et al.

... Many members of this Order are popular aquarium and experimental fishes.

Eight families, of about 88 genera, approximately 807 species per Nelson (1994).