CATFISH GENUS NOTURUS RAFINESQUE 95 



Pimelodus insignis Schomburgk (1841, p. 180 and plate VI in the 

 Natural History of the Fishes of [British] Guiana, vol. 1) is a primary 

 homonym of Pimelodus insigne Richardson (1836, p. 132). 



Ecological considerations. — As noted by examination of the 

 distribution map (map 5) of this species, the records are chiefly from 

 high-gradient streams above the Fall Line. Raney and Massman 

 (1954) and Greeley (1928, 1935, 1936, and 1937) have discussed the 

 ecology. A^. insignis lives in clear or normally clear water in moderate 

 to swift current, chiefly about rifiles of rubble, boulders, or coarse 

 gravel. 



Noturus insignis has been taken in collections containing Noturus 

 gyrinus, N. leptacanthus, N. gUberti, and N. furiosus. 



The FUNEBRis Group 



The funebris group, subgenus Schilbeodes, includes two allopatric 

 species, Noturus funebris and Noturus phaeus. They are found in the 

 lower Mississippi River system and other Gulf of Mexico tributaries 

 from the Red River and Bayou Teche, Louisiana, to Econfina Creek 

 in western Florida. Neither species is known from any of the streams 

 between the Mississippi and Pearl River systems, in the Florida 

 Parishes of Louisiana and southern Mississippi. It is in this region that 

 intermediates between the two species would be expected, but exten- 

 sive collections indicate their absence. Both are typical of permanent 

 springs and small, clear streams; they are commonly found beneath 

 submerged vegetation at the outlet and downstream from springs. 



In contrast to other species of Noturus the anal fin is long with 18 to 

 27 rays (table 17) and the dorsal spine is slender and somewhat 

 flexible, becoming stiff with age. The caudal fin has an intermediate 

 number of rays. Like Noturus insignis the hypurals are modaUy seven 

 (1-3+4-7) in both species. X-rays and skeletonized specimens indicate 

 a rather prominent mode of eleven vertebrae anterior to the origin 

 of the anal fin, suggesting that the anal fin is more anterior in position 

 than in other species except Noturus gyrinus and Noturus leptacanthus. 

 Unlike other Noturus, the flange or thin bone connecting the anterior 

 and posterior rami of the transverse process of the fourth vertebra 

 in the vertebral complex is very poorly developed or rudimentary. 

 The lateral boundary of this ledge of bone is very deeply concave in 

 contrast to that in other species where it is very shallowly concave to 

 moderately convex or with a nearly straight margin parallel to the 

 vertebral axis. 



The two species are almost uniformly darkly colored, with occasional 

 narrow darker bands near the margins of the dorsal, anal, and caudal 

 fins. Especially characteristic of the funebris group are the dark, 



