Leucotrichia riostoumae Thomson & Holzenthal,

Thomson, Robin E. & Holzenthal, Ralph W., 2015, A revision of the Neotropical caddisfly genus Leucotrichia Mosely, 1934 (Hydroptilidae, Leucotrichiinae), ZooKeys 499, pp. 1-100: 36-37

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Leucotrichia riostoumae Thomson & Holzenthal

sp. n.

Taxon classification Animalia Trichoptera Hydroptilidae

Leucotrichia riostoumae Thomson & Holzenthal  sp. n. Fig. 38


This species is similar to Leucotrichia forrota  and Leucotrichia inops  . These species share a similar combination of characteristics present in the phallus, as discussed under Leucotrichia forrota  . Of these species, Leucotrichia riostoumae  sp. n., is most similar to Leucotrichia inops  , as discussed under Leucotrichia inops  . Leucotrichia riostoumae  can be distinguished by the rugose ventral surface of the mesoventral process of sternum VII, which is lacking in Leucotrichia inops  . The membranous ridges along the apex of the phallus, which give it a star-like appearance when viewed dorsally, are also a feature unique to Leucotrichia riostoumae  .


Male. Length of forewing 3.6-4.2 mm (n=11). Head unmodified, with 3 ocelli; antennae unmodified. Dorsum of head dark brown with yellow and dark brown setae; thorax dark brown with bright yellow setae dorsally, dark brown ventrally; leg segments with dark brown setae. Forewings covered with fine dark brown setae with large patch of yellow setae on basal 2/3. Genitalia. Abdominal sternum VII with digitate, rugose mesoventral process with small basal ridge. Sternum VIII in ventral view with posterior margin concave. Segment IX anterolateral margin produced dorsolaterally, posterolateral margin convex; in dorsal view anterior margin concave, posterior margin broadly convex. Tergum × with dorsal sclerite simple; ventral sclerite with rounded projection on posterior margin; membranous apex small. Subgenital plate with dorsal arm digitate, broadest basally; ventral arm slender, digitate, in ventral view triangular. Inferior appendage basally subquadrate, apex rounded, without dorsal spine; in ventral view apically digitate. Phallus with basal loop not apparent; apex curving ventrad and laterad, with series of membranous spines appearing stellate in dorsal view.

Holotype male: ECUADOR: Imbabura: Reserva los Cedros, Río de la Plata, 00.32495°N, 78.78084°W, el. 1587 m, 18.x.2011, Holzenthal, Ríos, Encalada, and Acosta, (UMSP000140832) (UMSP). Paratypes: same data as holotype, 5 males (UMSP); same data as holotype, 3 males (MZUTI); same data as holotype, 2 males (NMNH).


Named in honor of Dr. Blanca Ríos-Touma, an aquatic ecologist and colleague who helped collect the holotype specimen.