Scientific Name
Cyprinodon arcuatus
Common Name
Santa Cruz pupfish
Biology
Dorsal
soft rays
(total): 9-10;
Anal
soft rays: 9 - 11;
Vertebrae: 25 - 27. Distinct dorsal-body surface, which is highly convex before the dorsal fin but changing abruptly at the dorsal origin into a deep, postdorsal concavity most developed in breeding males; absence in nuptial males of distinctive yellow or orange pigment on either the caudal fin or peduncle; weak development of lepidodonts and modally six preopercular pores (Ref. 43452).