TN00234 RIVER CHUB NOCOMIS MICROPOGON
Physical description: This chub has a small terminal barbel, and medium to large tubercles on the snout tip, lachrymal and as far back on the head as the posterior internasal area. The breast is naked and well scaled, with circumbody scales numbering usually from 30-33. The intestine is unwhorled, and the body is moderate to large with adults typically from 90-180 mm SL. The most post- erior tubercles rarely occure posterior to the internasal area, and a hiatus is usually present between the anterior snout and inter- nasal tubercles. The pharyngeal teeth number 4-4 and are moderately stout. The lateral line is complete and the scales number (37)38-40(43). There are (28)30-33-(36) circumbody scales, and (14)16-17(19) circum- peduncle scales. There are 8(9) dorsal rays, 18(19) principle caudal rays, 7(8) anal rays, 8 pelvic rays (15)17-18(19) pectoral rays. The gill rakers number (6)7-9(10). This species has a caudal fin that is perhaps always with pale orange or red orange distally. The peak color of the large nuptial male has a pink or rosy flush from the venter to the upper side. The dorsal and lower fins are edged with satiny white or yellow white. The lateral stripe of the nuptial males can be rapidly changed from blackish to pale green and back *4205*. Reproduction: Nst building occurs in late May and June, while spawning occurs during the nest building period *3129,3131,4205*. Fecundity is from 460-725 eggs per female *4205*. There is apparently only 1 spawning period per year *3131*. This species is mature and spawning at 3 years *4205,3057*. The breeding male curves the body around the female clasping her between the pelvic fin and the body *3131*. Behavior: The males show only minor territorial behavior over the nests in breeding season, with very little aggression toward male conspecifics *3131*. They may move to large streams or rivers to overwinter *3131*. The nest and spawning site is in clear, gravel bottom streams. 9-30 inches deep in runs with a moderate curent. The male builds a nest by digging a pit and removing stones with his mouth. He then fills the pit with gravel making a mound about 7.5 inches high and averaging 43 inches in diameter *3131,3057*. The newly hatched larvae are 5.8-6.5 mm, with incomplete development at birth. The yolk-sac is absorbed and the post larval phase begins at 10.0 mm. The late post-larval stage is at 13.9 mm *3024*. Origin: The origin of this species is native *4205*. Population parameters: The maximum age is 4 years *4205*. Data on aging using scales Is given in Lachner, 1952 *3057*. Aquatic/terrestrial associations: Other cyprinids that use this species nest include N. cornutus, N. rubellas, Campostoma anomalum, and Chrosomus erythrogaster *3131*. This species forms hybrids with N. cornutus and and Rhinichthys cataractae *3057,3133,3134*. PHYSICAL DESCRIPTION: ADULTS USUALLY 11-22 CM LONG, LARGEST SPECIMEN WAS 28.7CM AND 283 G LARGEST SPECIMENS ARE INVARIABLE MALES SNOUT OVERHANGS THE LARGE, SLIGHTLY OBLIQUE MOUTH SNOUT RATHER LONG CAUDAL SPOT USUALLY FAINT OR ABSENT, PROMINENT ONLY IN YOUNG GENERAL COLORATION IS BROWNISH CAUDAL FIN SLATISH OR OLIVE, BUT IS REDDISH OR ORANGE IN FISH LIVING IN POLLUTED WATERS BREEDING MALE HAS TUBERCLES ON HEAD RESTRICTED TO SNOUT AND INTERORBITAL REGION NO CARMINE SPOT BEHIND EYE OF BREEDING ADULTS *TN5056* BREEDING MALES DEVELOP BRIGHT BLUE AND GREEN COLORS AND A LARGE NUPTIAL CREST *TN5177* TERETE AND STOUT BODIED *TN5174* REPRODUCTION: MALES DEFEND NEST SPAWNING WITH ONE OR MORE FEMALES *TN5177* EGGS HATCH IN 5-6 DAYS *TN5188* AND HAVE A MEAN DIAMETER OR 2.6 MM (PRESERVED) *TN5189*
| Life History |
References for Life History Codes
3129, 3131, 3057, 3024, 3133, 3134, 4205
Comments on Life History Codes