MIXYTREMA SPOTTED SUCKERS 83 



MINYTREMA MELANOPS (RAFINESQUE) 



SPOTTED SUCKER; STRIPED SUCKER 

 (MAP XVII) 



Raflnesque, 1820, Ichth. Oh., 57 (Catostomus). 



G., VII, 19 (Catostomus fasciatus); J. & G., 136; M. V., 47; J. & E., I, 187; N., 48 

 (Erimyzon); J., 64; R, 80; F. F., II. 7, 444; L., 12. 



Body oblong, little compressed, adults becoming deeper, depth 3.9 to 

 4.5 in length. Size rather large, reaching a length of 18 inches. Head 

 olivaceous above, lighter olive to silvery on cheeks and opercles, with some 

 coppery; sides coppery above, greenish gray to silvery below; each scale 

 along sides with a quadrate spot of very dark greenish at base, the spots 

 forming rows lengthwise of body; belly greenish to silvery, with suggestions 

 of coppery luster; fins scarcely dusky, the membranes light greenish. Head 

 3.9 to 4.6 in length of body, its width 5.9 to 6.8, depth 5.3 to 6, rather flattened 

 above but not depressed; snout 2.3 to 2.7 in head, bluntly pointed; upper 

 lip with faint plicae, lower evidently plicate, its halves meeting at a rather 

 sharp angle; interorbital space 2.2 to 2.5 in head; eye small, 4.4 to 6.9 in 

 head, placed high, about midway of length of head. Dorsal rays 11 to 12, 

 not including rudiments, the fin higher than long, its position about midway, 

 usually a very little forward. Scales large, 6 or 7, 42-46, 5 to 7, regularly 

 imbricated, not crowded forward; lateral line incomplete in adults, in young 

 specimens imperfect or wanting. 



Head of old males covered with small tubercles in spring. 



This species is found in the Great Lake region, the upper 

 Mississippi Valley as far north as the Yellowstone, southward 

 and southwestward to the Gulf and to Texas, and on the 

 Atlantic slope from New Jersey to North Carolina. In Illinois 

 it has been taken in all our stream systems, including the Lake 

 Michigan drainage, but most abundantly in the Wabash and 

 the Kaskaskia basins. In proportion to the number of collec- 

 tions made, it has been found in central Illinois twice as 

 frequently as in northern, and in southern Illinois twice as fre- 

 quently as in central. It is mainly a species of creeks and the 

 smaller rivers twice as abundant in the former as in the latter 

 and is comparatively rare in lakes and ponds. It grows to a 

 length of 18 inches, but is not abundant enough in Illinois to 

 have any noticeable value. From the little that is known of its 

 food we may surmise that it lives largely on mollusks and 

 insect larvae. 



