Revision of the genus Eotrechus Kirkaldy (Hemiptera, Heteroptera, Gerridae), with descriptions of six new species Author Tran, Anh Duc https://orcid.org/0000-0001-9605-0739 Faculty of Biology, University of Science, Vietnam National University, Hanoi, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam tran.anhduc@hus.edu.vn Author Zettel, Herbert https://orcid.org/0000-0002-7760-0472 Herbert Zettel, 2 nd Zoological Department (Entomology), Natural History Museum Vienna, Burgring 7, 1010 Vienna, Austria Author Sites, Robert W. https://orcid.org/0000-0002-3895-813X Enns Entomology Museum, University of Missouri, Columbia, MO 65211, USA text Deutsche Entomologische Zeitschrift 2023 2023-03-16 70 1 69 111 http://dx.doi.org/10.3897/dez.70.97117 journal article http://dx.doi.org/10.3897/dez.70.97117 1860-1324-1-69 99BBA4C8ED2048879952B61CC25309D4 CA0CBE818BFA5DFA80DBD42521D5DBE3 Eotrechus pilicaudatus Tran & Zettel, 2006 Fig. 24 Eotrechus pilicaudatus Tran & Zettel, 2006: 40-43, figs 1-8 (type locality: Meghalaya, NE India). Material examined. Holotype : India • ♂ (apterous); Meghalaya , 3 km E Tura ; 25°30'N , 94°14'E ; 1150 m a.s.l. ; 18 Apr. 1999 ; L. Dembicky & P. Pacholatko leg.; NHMW. Diagnosis. Size: apterous male: length (excluding genitalia) 6.50; width 2.40. Mesosternum ca. 4.0 x length of metasternum. Male: fore femur incrassate at basal part and tapering towards apex; middle and hind trochanters and basal part of middle and hind femur with many small spines; sternum VII about twice as long as two preceding sterna combined, posterior margin slightly emarginated. Male genitalia: abdominal segment VIII large; pygophore suboval, without lateral projections but with large tufts of long, black posterolateral setae, posterior margin with paired, small, pointed, black processes consisting of tightly packed, thick setae; proctiger with paired long, bristle-like, black setal tufts distolaterally. Female unknown. Remarks. This species is unique in having thick pilosity on the genitalia. Based on the absence of a caudal projection on the pygophore, this species can be placed in the E. hygropetricus species group. A comparison between E. pilicaudatus and E. hygropetricus was discussed in detail by Tran and Zettel (2006 : 41, 43). Distribution. India: Meghalaya ( Tran and Zettel 2006 ) (Fig. 24 ). Eotrechus longipes species group Diagnosis. Male: fore femur moderately incrassate, tapering towards apex; posterior margin of sternum VII emarginated medially; genitalia large: pygophore with a pair of posterolateral projections; proctiger slender, with subtriangular apex. Female: sternum VII 1.1-1.5 x length of two preceding sterna combined, posterior margin medially produced (except in E. anderseni sp. nov.); genitalia visible in lateral view (only partly visible in E. anderseni sp. nov.). Species included. E. longipes Andersen, 1982, E. terrestris Andersen, 1982, and E. anderseni sp. nov.