Smicridea (Smicridea) frequens (Navás 1930)

(Figs. 9–13)

Rhyacophylax frequens Navás 1930: 362, 1932: 83, 1934: 28; Fischer 1963: 136.

Smicridea frequens: Schmid 1950: 347 –348 [sub Smicridia]; Flint 1967: 55; Fischer 1972: 144. Smicridea (Smicridea) frequens: Flint 1974b: 88; Flint 1989: 23 (redescription); Flint et al. 1999.

Description

Larva. Length: 6.8 to 8.2 mm (n=12). Head capsule, in dorsal view, subcircular; dark reddish brown, with pale (yellowish) zones around stemmata, with transverse band in posterior region of parietal apotomes, and lateral longitudinal bands joining these 2 areas (Fig. 9). Anterior margin of frontoclypeal apotome crenulate; median depression slightly marked. Parietal apotomes with dark reddish brown muscle scars, distributed characteristically as in Figs. 9–10. Lateral muscle scars similar to that of S. (S.) annulicornis . With posterior ventral apotome. Distribution of muscle scars on pro­, meso­ and metanota as in Fig. 11. Poststernal sclerites of prosternum lacking. Mesosternum with 2 posterolateral subtriangular sclerites. Abdominal sternum VIII with 2 triangular sclerites bearing setae.

Pupa. Length: 5.8 mm (n=4). Labrum with anterior margin rounded, with 2 rows of 4 to 5 long setae in anteromedian region; lateral lobes with 4 to 5 long setae (Fig. 12). Mandibles similar to those of S. (S.) annulicornis . Dorsal abdominal plates of segments II to IV wider than long, those of segments V to VIII longer than wide. All plates with large posterior teeth intercalated with small ones, except IIIp bearing large anterior teeth and small ones in median region (Fig. 13).

Material examined

ARGENTINA: Chubut Province: Trevelin, Río Nahuel Pan (road to Tecka), 11.ii.1993, 11 larvae; Trevelin, Río Percey, 6.ii.1993, Angrisano & Valverde, 4 pupae; Río Negro Province: El Bolsón, Río Quemquemtreu, 15.ii.1993, Angrisano, 1 larva, 1 pharate female, 1 pharate male.

Distribution

Argentina (Chubut Province, Neuquén Province, Río Negro Province); Chile.