The Trichoptera of Panama. XIX. Additions to and a review of the genus Leucotrichia (Trichoptera, Hydroptilidae) in Panama Author Thomson, Robin E. https://orcid.org/0000-0002-5883-2040 University of Minnesota, Department of Entomology, 1980 Folwell Ave., St. Paul, MN 55108, USA Author Armitage, Brian J. https://orcid.org/0000-0003-3182-1533 Museo de Peces de Agua Dulce e Invertebrados, Universidad Autonoma de Chiriqui, David, Panama tobikera89@gmail.com Author Harris, Steven C. Department of Biology and Geosciences, Clarion University, Clarion, PA, USA text ZooKeys 2022 2022-07-11 1111 425 466 http://dx.doi.org/10.3897/zookeys.1111.77371 journal article http://dx.doi.org/10.3897/zookeys.1111.77371 1313-2970-1111-425 8474125F447546C3A6DCC46F7D038BDC 028D93AD33835AD589E06F29DAE7580C Leucotrichia ruiteri sp. nov. Figs 2A , 14 Type locality. Panama: Chiriqui Province : Cuenca 108; Boquete District; Quebrada Jaramillo, Finca Monterey; 8.7632°N , 82.41383°W ; 1,214 m a.s.l. Type material. Holotype : male, Panama: Chiriqui Province : Cuenca 108; Boquete District; Quebrada Jaramillo, Finca Monterey; 8.7632°N , 82.41383°W ; 1,214 m a.s.l.; 8-12 Jun. 2018, K. Collier, leg.; Malaise trap; in alcohol; MIUP-004-T-2021. Paratype : same data as for holotype; 1 male; UMSP. Other material examined. Panama : Chiriqui Province • 1 male ; Cuenca 102, Renacimiento District ; La Amistad International Park , Rio Candela , Finca Felix , PSPSCB-PILA-C102-2017-021; 8.90614°N , 82.72882°W ; 1,799 m a.s.l. , 1-5 Sep. 2017 ; E. Alvarez , T. Rios , E. Perez , leg.; Malaise trap ; in alcohol; COZEM . Veraguas Province • 1 male ; Cuenca 132, Santa Fe National Park , Rio Mulaba , 2do Brazo , PSPSCB-NPSF-C-097-2017-007; 8.52577°N , 81.13045°W ; 623 m a.s.l. ; 19-23 Apr. 2017 ; A. Cornejo , T. Rios , E. Alvarez , C. Nieto , leg.; Malaise trap ; in alcohol; MUPADI . Diagnosis. Leucotrichia ruiteri sp. nov. is most similar to L. hispida , as both species bear prominent setae on the posteroventral production of sternum VIII, a bilobed phallus apex, and a similar shaped inferior appendage. Leucotrichia ruiteri can be separated by the single, elongate seta on sternum VIII compared to the cluster of setae present on L. hispida . Additionally, the forewings of L. ruiteri are modified with a large setae-filled pocket, while those of L. hispida are unmodified. Description. Male. Length of forewing 2.0-2.1 mm ( n = 4). Forewing with large pocket filled with scales (Fig. 2A ); hindwing unmodified. Head unmodified, with three ocelli; antennae unmodified. Tibial spur count 1, 3, 4. Color in alcohol brown. Genitalia . Abdominal sternum VII slender, elongate (Fig. 14A, D ). Sternum VIII with posteroventral production bearing prominent apical seta (Fig. 14A ); in ventral view posterior margin concave (Fig. 14D ). Segment IX anterolateral margin convex, posterolateral margin straight with slight irregularity (Fig. 14B ); dorsally, anterior margin concave, posterior margin broadly convex (Fig. 14C ). Tergum X with dorsal sclerite with irregular dorsal margin; ventral sclerite semi-elliptic with knoblike projection mesally on posterior margin; membranous apex subquadrate (Fig. 14B, C ). Subgenital plate with dorsal arm simple, with slight preapical emargination on dorsal margin, apex truncate (Fig. 14B ); ventral arm narrowing apically, ventral margin slightly sinuate, in ventral view subovate with narrow basal projection and small rounded apical emargination (Fig. 14B, D ). Inferior appendage broadest mesally, with small dorsal subapical peg-like seta, apex rounded (Fig. 14B ); ventrally slender, with digitate basal projections, apex slightly hooked on inner margin (Fig. 14D ). Phallus tubular basally, constricted at midlength with typical median complex bearing basal loop and pair of spherical "windows" ; apex membranous with internal sclerotized structures and two apical lobes extending dorsad (Fig. 14E, F ). Figure 14. Leucotrichia ruiteri sp. nov. Male genitalia: A segments VII-VIII and segment IX margin, lateral B segments IX-X, lateral (base of phallus crosshatched) C segments IX-X, dorsal D segments VII-IX, ventral E phallus, lateral F phallus, dorsal. Distribution. Panama. Etymology. This species is named in honor and memory of Dave Ruiter, a passionate and enthusiastic caddisfly researcher and good friend, who recently passed away.