Culoptila rusia Mosely Fig. 31 A, B Culoptila rusia Mosely 1954: 341. This is a distinctive species, most similar to C. pararusia. In both species tergum X is distinctly curved and apically acute, and the apices of the ventrolateral processes are also sclerotized and strongly bent or curved. Both species also have the phallobase inflated and possessing 2 long internal spines. Primary differences are in the shape of the phallic spines, which are stout, straight, and subequal in length in C. pararusia, and always with one spine strongly curved in C. rusia and with the other elongate and very narrowly tapered apically. Also, the inferior appendages are acute apically in C. rusia and bluntly rounded in C. pararusia Among Costa Rican species with an apically acute tergum X, only C. costaricensis has 2 phallic spines. It differs in the shape and length of the spines, as well as in the shape of the phallobase. Adult. Length of forewing: male 2.5–3 mm; female 2.7–3 mm. Color light brown; wing with only indistinctly evident crossband at anastomosis. Mesothorax of male not noticeably modified; mesoscutal wart short, heart­shaped; mesoscutal setae short. Mesothoracic tegulae of male flattened and weakly cupped, distinctly enlarged; tegular setae long; tegular gland short, pleated, concertina­like. Male genitalia. Sternum VI process short, subtruncate. Tergum IX ventral margin rounded, tapered from anterolateral margin, distinctly produced posteroventrally. Inferior appendages short, subacute apically. Tergum X long, length greater than width, and distinctly curved, apex in ventral view acute; ventrolateral processes with apices incurved and posteriorly bent, bend prominent and strong, approximately right angle; apices of lateral processes much narrowed, inner margin of apex bluntly rounded, not acute. Phallobase large, broadly rounded in lateral view, apicodorsal projection elongate, with slight upward inflection at base, apex subacute. Phallic apparatus with 2 phallic spines, both elongate narrow, about 2/3 to 3/4 length of phallobase, one nearly straight, other with recurved base and distinct sinuous curvature. Material examined GUATEMALA: Chimaltenango, 19–20.viii.1965 (P.J. Spangler) — 71 males, 66 females (NMNH). MEXICO: Chiapas: Río Mixcum, Cocahuatan, 23.iii.1985 (H. Velasco) — 4 males (NMNH); Unión Juárez, Puente Colorado, ca. Tapachula, 14.iii.1984 (J. Bueno­Soria) — 7 males, 2 females (UNAM); Tapachula, Río Mixcum, 26.iii.1985 (H. Velasco) — 10 males (UNAM); Veracruz: Pte. Tacolapan, E. Tejada, 4.xii.1975 (C. & O. Flint) — 1 male (NMNH). Distribution MEXICO (Chiapas, Veracruz); GUATEMALA.

Published as part of Blahnik, Roger J. & Holzenthal, Ralph W., 2006, Revision of the genus Culoptila (Trichoptera: Glossosomatidae), pp. 1-52 in Zootaxa 1233 on page 38, DOI: 10.5281/zenodo.172764