CATFISH GENUS NOTURUS RAFINESQUE 137 



operculomandibular pores; and a prominently blotched color pattern 

 with the pigment extending across the lower side of the body almost 

 to the ventral surface. 



Description. — Typical specimens are short and chunky, the 

 abdominal region and head being relatively large and heavy. In 

 contrast to lautus the caudal region may be short (note the 25 to 27 

 caudal vertebrae in cleared and stained specimens) and the numbers 

 of vertebrae and anal rays average fewer (tables 10 and 12). 



General background coloration yellowish or straw color; side and 

 dorsal surface with dark brown chromatophores forming rather 

 prominent saddle-like blotches, alternating with lighter obovate 

 areas on the back and upper side; midside of body rather densely 

 pigmented; pigment on lower sides slightly lighter and less dense 

 or lower side strongly variegated; first dorsal saddle beginning just 

 before the dorsal fin and extending backward to the third dorsal ray; 

 a second, about as long, lies midway between the dorsal and adipose 

 fins; a third slightly longer, at the middle of the adipose fin extends 

 variably, usually to the margin in adults, onto that fin, which is 

 otherwise nearly immaculate; an irregular bar crosses the upper and 

 lower procurrent rays and the rear portion of the caudal peduncle. 



Caudal fin dusky, without obvious light areas except rear margin; 

 submarginal dark brown caudal band broad, becoming diffuse ante- 

 riorly; also present, a short medial, narrow vertical crescent of dark 

 brown pigment or intermediate band; soft dorsal fin immaculate 

 except a few scattered chromatophores distally and dark brown ba- 

 sally; membrane over dorsal spine heavily pigmented, the heavy 

 dark brown pigment extending from near the spine tip diagonally 

 downward to the base of the third soft ray; bases of rear dorsal rays 

 with little pigment. A few irregularly placed chromatophores distally 

 on longer anal rays and scattered over the pectoral fin, usually on 

 the longer rays, but covering the pectoral spine; pehdc fins immaculate; 

 undersurface of head (except lightly pigmented area in front of 

 barbels), abdomen, and inner mental barbels unpigmented; outer 

 mental barbels sometimes with a few brown chromatophores; upper 

 barbels with dense dark brown pigment; top of head dark brown; 

 a dark bar crosses the back of the head, extending onto the operculum 

 and upper branchiostegal membrane; another, below the eye, ex- 

 tends forward to the nares ; a light area behind the eye has fine chromat- 

 ophores; the cheek has relatively little pigment. 



Type.— The holotype, UMMZ 157620, a female, is 41.3 mm. in 

 standard length. It has 13 anal rays, 17+7-1-9+12=45 caudal rays, 

 and 6 soft dorsal rays. On each side there are eight pelvic rays, nine 

 soft pectoral rays, five serrae on the posterior edge of the pectoral 

 spine, two internasal pores, eleven preoperculomandibular pores, and 



