Mayfly Species Serratella serrata (Little Sooty Olives)

A brightly colored species; eyes of male orange-red, body brighter brown than E. deficiens (now a synonym of Teloganopsis deficiens) or E. sordida (now a synonym of Serratella serrata).

Eyes of living male orange-red; head brown, lighter in front. Antennae pale brown. Thorax yellowish dorsally, shaded with brown. Posterior margin of mesonotum margined with brown; pleura with brown shading. Sternum pale with median and lateral dark brown areas. Legs pale; femora banded with brown apically. Wings hyaline, tinged with brown at the base; veins pale. Abdomen brown dorsally, pale ventrally, with no curved row of dark dots such as occur in E. serratoides (now a synonym of Serratella serratoides). Tails pale, the basal joinings brown.

Described as E. sorida

Body length 5 mm, wing length 6 mm

A species of the serrata group (now a synonym of Serratella serrata); male imago duller in color than E. deficiens (now a synonym of Teloganopsis deficiens) with tails unmarked.

Eyes deep blackish brown. Head and thorax blackish brown; pleura with lighter brown shading; lateral extensions of mesosternum paler. Head of female “light ruddy ochreous” (McD.). Legs pale yellowish, fore legs somewhat tinged with smoky. Middle and hind femora with indications of brown spots apically. Fore tibia twice the length of the femur, and slightly longer than the entire tarsus. Wings hyaline, all veins pale. Abdominal tergites dull blackish, the three posterior segments brownish. Sternites paler, rather smoky, becoming opaque and pale grey posteriorly. Genitalia and tails whitish; tails unmarked. Penes as in fig. 156.

Head of nymph somewhat roughened on the vertex, but with no distinct occipital tubercles. Feeble wart-like processes on each side of the median line of the prothorax. Dorsal spines represented by wart-like spicule-bearing processes. Gills present on tergites 3-7. Postero-lateral spines become increasingly acuminate to rearward, that on the 9th segment extending beyond the end of segment 10. Lateral margins of abdominal segments bear conspicuous spinules. Tails pale, with a median band of dark brown. Each claw with 3-4 denticles. General color brown; legs and venter paler; tergites 5-6 with brown pencilings. Abdominal sternites marked with a lateral row of dark dashes, but with no curved row of dark dots between these rows.

Described as E. sorida

Head and thorax of nymph smooth, but quite hairy. Dorsal spines represented by the usual wart-like processes. Postero-lateral spines longer than in any other species of this group; the spine on segment 9 extends well beyond the 10th segment. Gills on segments 3-7. Legs hairy, the anterior margin of the femora with a few spinules. General color pale yellowish brown to olive; no ventral markings. Femora usually dark with pale bands; tibiae pale with a wide median dark band; tarsi dark basally. Tails pale, without dark markings.