TN00333 MOUNTAIN REDBELLY DACE PHOXINUS OREAS
Physical description: This is a small, fine scaled, blotched- back minnow whose dark midlateral stripe is partly or entirely disaligned at midlength and has an extension deflected toward the anal fin. The adults are usually from 40-55 mm SL. The body form is moderate, tending to be somewhat robust in the nominate form, and somewhat elongate in the Tennessee form. The dorsal fin origin is usually distinctly posterior to the pelvic origin. The head is moderate and the eye is moderate or small and lateral. The snout is pointed or narrowly rounded and the frenum is absent. The mouth is small, subterminal and nearly horizontal. The intestine is long and whorled and the peritoneum is dark. The tubercles of the male are small to tiny and present over much of the head, body and most fins. They are elaborated as a patch on the upper operculum, comblike rows on the breast and incrustaceans on the lower caudal peduncle. They have 5-5 pharyngeal teeth and the lateral line is incomplete. There are (63)68-78(81) midlateral scales in the nominate form and (74)77-88(95) in the Tennessee form. There are (27)28-34(35) horizontal scale rows, 8 dorsal rays, 19 principal caudal rays, (7)8(9) anal rays, (6)8(9) pelvic rays and (13)14-16(17) pectoral rays. The young and juveniles are olive above with a silver side and dusky lateral stripes. The belly is white. The nuptial male has a background shade of tan or olive with all dark marks and areas black, jet black in peak. The lower side and belly are intense scarlet with red also on the tip and lower side of the snout, upper and lower operculum, the underside of the pectoral fin basally and along the base of the dorsal and lower fins. The iris is silver or gold where it is not black. The lower fins are moderate to brilliant yellow and the dorsal and caudal fins are pale dusky or pale yellow. There is a pearly silver-white area below the eye, along the upper and lower edges of the operculum, and at the bases of all fins encircling the pectoral base and sometime absent from the dorsal, caudal and anal bases. The nuptial female is subdued, usually with little or no red, silver or gold. Sometimes the red is moderately developed and the dusky areas, including the chin, are dusky to diffusely black in some individuals. The fins are as in the male *4205*. Reproduction: The breeding season extends from April through June with water temperatures from 15-25.3 degrees C and a mean of 20.9 degrees C. They spawn on the nests of Nocomis leptocephalus, or on gravel in the absence of nest builders. Usually 25-100 males hold low over a nest and as the females enter the nest they are swarmed by 2-10 males *4205*. After spawning other males ate up many eggs *3058,3136*. Behavior: The males keep small territories during spawning periods *3058*. The spawning sit is located in or above riffles in shallow water, and other spawning sites are unknown *3058*. In two Virginia populations they fed exclusively on algae and detritus. In North Carolina, they also consumed aquatic insects *4205*. Origin: This species is native in Virginia *4205*. Aquatic/terrestrial associations: This species hybridizes with Notropis cerasinus, the crescent shiner, probably as a result of synchronous spawning over Nocomis nest *3135*.
| Life History |
References for Life History Codes
3058, 3136, 3135, 4205
Comments on Life History Codes