TN00129 SWANNANOA DARTER ETHEOSTOMA SWANNANOA
Physical description: This is a laterally barred darter of moderate size with the adults usually 50-75 mm SL. The body is moderate to robust in profile, slightly to moderately compressed; snout short and blunt; frenum well developed; branchiostegle membranes broadly conjoined; caudsal fin slightly emarginate or truncate. Breading male with tubercles, in the form of thickened pads that are often elevated and pointed, on lower body scales. Ridges present on rays of lower fins; female nontuberculate except as noted above. Female genetal papilla tubular, thick ponderously long, the longest among the darters. The lateral line is complete, scales (46)48-58(62); scales above lateral line 6-8(9); scales below the lateral line(5)6-7(8); circumpeduncle scales (15)17-22(23). Dorsal spines (10)11-13; dorsal rays (11)12-13(14); anal spines 2; anal rays (7)8-9; pctoral rays (14)15-16(17). Breast cheek and opercle naked; nape and belly usually fully scaled. The adult female upper body is pale to dark olive with darker lateral markings; lower side pale yellow or satiny cream; venter cream. Rows of dusky orang-red spots present on upper and midside of large females. Lower head breast and basal half of genital papilla turquoisein some, wholly pale in others. First dorsal distal and basal bands and pectoral base pale orange. Several ventral rays of caudal, basal half of anal and pelvic base light turquoise in some. Prenuptial and most nuptial males with ground color of upper head and body tan to tan-olive, side of body grading creamy olive dorsolaterally to satiny white ventrally; spots forming longitudinal rows rusty orange to brown; bars dark to pale olive, some with hint of turquoise diffusing ventrad; lower head and breast varying shades of turquoise; iris dusky coppery to bright orange. First dorsal spine tip white; distal band yellow-orange to orange-red; submarginal to submedial streakes red-brown to proximally, blackish olive; epibasally along much of the fin. Second dorsal membrane streaks largely orange-red to red- brown; rays yellow-olive to olive-brown. Caudal membranes brown or orange distally in some specimens, upper base and lower portion of fin turquoise, elsewhere, membranes and rays olive; upper and lower areas of caudal base pale tan. Anal and pelvic turquoise, pale orange distally in some fish; pectoral base bronze, rays olive dorsally to salmon ventrally. Small adult males with lesser developement of turquoise, orange and red. In medium-size nuptial males, turquoise was more intense and was replaced by emerald green in some ares, additionally bright green occured over entire underside of head and body and almost all of the caudal. These fish rapidly developed and lost reddish in the second dorsal and caudal, altered the body ground shade fromcreamy to dusky, and varied the intensity of the lateral bar *4205*. Reproduction: The spawning period is suggested to be April and May based on the presence of tubercles on males from late March to early June. The probable spawning habitat was rubble and smal gravel in riffles 30-45 cm deep. When Little River fish were introduced to an aquarium, a few times two males laterally displayed with fins erect and chased each other by tight circling. One male spawned several times with one of the five ripe females. The female buried herself partially in fine to pea-sized gravel, and then was mounted by the male. The diameter of six striped ripe ova ranged from 1.9-2.2 mm, with a mean of 2.1 *4205*. Behavior: This dartwe is a typical swift-water benthic insectivore. They take immature mayflies, caddisflies and midges *4205*. Limiting factors: Cool water is probably an important habitat parameter of this species. Most males and females spawn first at age 2 *4205*. Population parameters: Most males and females spawn at age-2 and a few at age-1 *4205*.
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4205
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