Cryptomyrus Sullivan, Lavoué and Hopkins 2016

Diagnosis

Cryptomyrus gen. n. is distinguished from all other mormyrid genera by combination of the following features. Scales large: 44 or 45 along the midlateral line, with about 42 pierced lateral line scales; mouth subinferior; broad but nonprotrusive chin swelling that does not extend beyond snout; snout expansive and rounded in lateral profile with slight inflection point visible above anterior margin of eye in lateral view; snout somewhat v-shaped in dorsal view; eye large, 19–20% HL; middle four teeth on dentary squarish, broad and spatulate, oriented nearly horizontally, central two lower teeth longest along inner edges and in contact with each other, jutting in advance of neighboring pair and forming a trowel-like shape (Fig. 6); ventral profile of head with marked concavity between gular region and chin, body depth increasing rapidly from there to pelvic-fin origin, body depth at pelvic-fin origin 21–24% SL; interorbital width 32–35% HL; dorsal-fin length 78–88% of anal-fin length; caudal-peduncle depth at end of anal fin greater than 30% of caudal-peduncle length; faint, wide and diffuse band of pigment between anterior portion of dorsal fin and anal-fin bases, darkest from midlateral region dorsally.

Comparisons

Very few Mormyrinae have so few midlateral scales. Only some of the large-scaled Marcusenius such as Marcusenius moorii (Boden et al. 1997) and smaller species of Stomatorhinus and Pollimyrus are in the same range. Cryptomyrus has a more pronounced chin swelling than Ivindomyrus and Paramormyrops, although it does not protrude forward beyond the snout as in Marcusenius. Cryptomyrus has a noticeably more fusiform body shape and larger eye (19–20% HL) than Paramormyrops (eye 11–16% HL), the most speciose mormyrin genus in Gabon and Lower Guinea, which also lacks the band of pigment between the dorsal and anal fins.

Etymology

Gender masculine; from the Greek kryptos meaning secret or hidden referring to the rarity of these fishes in collections and the Greek myros, a kind of fish, a suffix used in the names of many other mormyrid genera.