124 FISHES OF ILLINOIS 



GENUS OPSOPCEODUS HAY 



Body fusiform, somewhat compressed; mouth extremely small, terminal; 

 upper jaw protractile; no barbels; teeth 5-5 or 4-5, with edges serrated and 

 no grinding surface, the tips hooked; intestine short; peritoneum white; 

 dorsal rays 7 to 10; anal rays 7 or 8; scales 37 to 42; lateral line complete or 

 imperfect. Size very small, 2 1/2 inches. Species 3 or 4; confined to the 

 Mississippi Valley and the eastern United States. 



FIG. 27 

 OPSOPCEODUS EMILIA HAY 



(MAP XXX) 



Hay, 1880, Proc. U. S. Nat. Mus., 507. 



Forbes in J. & G., 247 (Trycherodon megalops); M. V., 68; J. & E., I, 248 (megalops); 

 P., 74; L,., 15 (emiliae and megalops). 



The very small and upturned mouth, the black spot on the posterior 

 rays of the dorsal fin, and the incomplete lateral line of this species serve to 

 distinguish it readily from all other minnows found in our range. Length 

 usually less than 2^ inches; body moderately elongate, compressed, the 

 back perceptibly elevated, the profile a more or less even incline from a point 

 over the tips of the reflexed pectorals; depth 4.1 to 4.8 in length; caudal 

 peduncle slender, longer than head, its depth 2.2 to 3.2 in its length, not 

 usually, however, over 2.5. Color light olive, yellowish, the scales except 

 on and very near belly conspicuously dark-edged;* a narrow dark lateral 

 band, extending forward across opercle and through eye to end of snout, 

 becoming faint anteriorly; no distinct caudal spot, but sometimes, in highly 

 colored males, an indistinct vertical bar at base of caudal; fins of females 

 plain, or, at most, the dorsal with faint traces of dusky on anterior third; 

 breeding males with the snout and chin thickly studded with minute tubercles, 

 and with a large blotch of dusky covering almost entire dorsal fin except a 

 patch at base and another at tip of fin; a second blotch of dusky at back of 

 fin in some males, situated about half way up from base and crossing last 

 three rays; other fins plain. Head small, 4.2 to 4.5 in length; width of head 



* No other species of Cyprinidce found in this state has the cross-hatching more distinct or 

 extending farther below the lateral line, typical specimens having almost the entire body so 

 marked. 



