Leucotrichia tapantia 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: 40

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Leucotrichia tapantia Thomson & Holzenthal

sp. n.

Taxon classification Animalia Trichoptera Hydroptilidae

Leucotrichia tapantia Thomson & Holzenthal   sp. n. Fig. 41


This species is similar to Leucotrichia bicornuta   , Leucotrichia dianeae   , and Leucotrichia extraordinaria   . These species share a similar combination of characteristics present in the phallus and the posterolateral margin of sternum VIII, as discussed under Leucotrichia bicornuta   . Of these species, Leucotrichia tapantia   sp. n., is most similar to Leucotrichia dianeae   . Each has a large tuft of prominent setae at the apex of the posterolateral projection of sternum VIII; a small, mesal projection on the posterior margin of sternum VIII, and larger, more prominent apical lobes on the phallus apex than either Leucotrichia bicornuta   or Leucotrichia extraordinaria   . Characteristics that can be used to distinguish Leucotrichia tapantia   from Leucotrichia dianeae   include a much longer basal loop of the phallus midlength complex and the absence of a dorsal arm on the subgenital plate. The prominent apical spine of the ventral arm on the subgenital plate, when viewed ventrally, and the presence of 2 small dorsal setae, in addition to the single dorsal spine on the inferior appendage separate Leucotrichia tapantia   from all 3 of the other species.


Male. Length of forewing 3.4-3.9 mm (n=19). Head unmodified, with 3 ocelli; antennae unmodified. Dorsum of head dark brown with yellow setae; thorax dark brown with yellow setae dorsally, brown ventrally; leg segments with brown setae. Forewings covered with fine dark brown setae with broad streak of yellow setae down outer edge. Genitalia. Abdominal sternum VII with short, pointed mesoventral process. Sternum VIII lateral projection elongate, extending dorsad, apex bearing tuft of prominent setae (Fig. 41B), in ventral view with posterior margin concave with digitate mesal projection (Fig. 41D). Segment IX anterolateral margin convex, posterolateral margin convex; in dorsal view anterior margin concave, posterior margin straight. Tergum × with dorsal sclerite slender; ventral sclerite semielliptic with crenulate posterior margin; membranous apex small. Subgenital plate with dorsal arm not apparent; ventral arm slender, sinuate, broadest mesally, in ventral view with apical spine very prominent. Inferior appendage straight, bearing 1 large dorsal spine and 2 small setae; in ventral view fused basally, digitate. Phallus apex bearing internal apodemes and pair of prominent apicodorsal lobes.

Holotype male: COSTA RICA: Cartago: Reserva Tapantí, waterfall, ca. 1km (road) NW tunnel, 9.69°N, 83.76°W, 2-3.viii.1990, el. 1600m, Holzenthal, Blahnik, Muñoz (UMSP000201359) (UMSP). Paratypes: same data as holotype, 46 males (UMSP); same data as holotype, except 10.vi.1988, C.M. and O.S. Flint, R.W. Holzenthal, 13 males (NMNH).


Named for Reserva Tapantí, the location where the holotype was collected. The name was suggested by Dr. Steve Harris, an aquatic biologist and Trichoptera  taxonomist at Clarion University, who first recognized the species as new.