MIXYTREMA SPOTTED SUCKERS 83 



MINYTREMA MELANOPS (Rafinesque) 



(spotted sucker; striped sucker) 



Rafinesque, 1820, Ichth. Oh., 5 7 (Catostomus i. 



G , VII, 19 (Catostomus fasciatus); J. & G.. 136; M. V., 47; J. & E., I, 1S7; N., 4S 

 (Erimyzoni; J., 64; F., SO; 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 ; inter- 

 orbital 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 mid- 

 way, 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 Mis- 

 sissippi Valley as far north as the Yellowstone, southward and 

 southwest ward 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 pro- 

 1 >< >rti< in to the number of collections made, it has been found in cen- 

 tral Illinois twice as frequently as in northern, and in southern 

 Illinois twice as frequently 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 comparativelv 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. 



Genus CATOSTOMUS Le Sueur 



(FIXE-SCALED SUCKERS) 



Head more or less elongate; mouth inferior, the upper lip thick, 

 protractile, papillose; lower lip greatly developed, incised behind so as 



