Redescriptions of Homoplectra japonica (Banks 1906) and H. albomarginata (Ulmer 1907) (Trichoptera, Hydropsychidae), with descriptions of five new similar species from Japan Author Nozaki, Takao text Zootaxa 2025 2025-01-08 5566 2 303 328 https://doi.org/10.11646/zootaxa.5566.2.4 journal article 307804 10.11646/zootaxa.5566.2.4 5b17f3b8-cf94-4ec4-a888-0519b0b344de 1175-5326 14702954 9866D791-F9AA-4701-9EBC-B3A52613C657 Homoplectra flagelliformis sp. nov. ( Figs 6 , 13 ) Diplectrona japonica nec Banks 1906 : Kawase & Hayashi 2010 , p. 85 . Misidentification . Diplectroninae Gen. japonica Species Complex: Nojima 2017 (in part), p. 119. FIGURE 6. Adults of Homoplectra flagelliformis sp. nov. 6A–6F, male genitalia, type locality (Okuizumo-cho, Shimane): 6A, left lateral, apicomesal part of inferior appendage, enlarged; 6B, dorsal, 6C, ventral; 6D, phallic apparatus, left lateral; 6E, same, dorsal; 6F, phallotheca, treated by KOH, left lateral. 6G & 6H, variations of male genitalia (Hatsukaichi-shi, Hiroshima): 6G, posteroventral lobe of segment IX, ventral; 6H, phallotheca, left lateral. 6I–6K, female genitalia, type locality: 6I, left lateral; 6J, dorsal; 6K, ventral. 6L, lobe formed by sclerotized ribs on vulvar scale, variation (Hatsukaichi-shi, Hiroshima), ventral. Diagnosis. The male of this species is very similar to that of H. japonica in the short antennal scapes and the shape of the phallic apparatus; but can be distinguished by the shape of the ventral processes of the phallotheca and aedeagus: In this species, the ventral processes of the phallotheca are almost straight apically ( Figs 6D, 6H ), and the stem of the aedeagus bears a pair of round lobes apically in lateral aspect ( Fig. 6D ); but in H. japonica , the ventral processes of phallotheca curve dotsomesad apically ( Figs 3D, 3E ), and the posterior margin of the aedeagal stem is truncate in lateral aspect ( Fig. 3D ). The female of this species is similar to that of Homoplectra shikoku sp. nov. , in having a trapezoidal basoventral lobe on the vulvar scale but these species can be easily distinguished from each other by the shape of the lateral lobes of segment VIII: The mesal margin of each lateral lobe is concave in the middle in this species ( Fig. 6K ), but it is smoothly convex in H. shikoku sp. nov. ( Fig. 7K ). Description Adult. Length of antennal scape and general coloration of body and wings very similar to those of H. japonica . Wings occasionally uniformly dark brown in female. Forewings each 8.5–10 mm in male (n = 10), 10.5–13 mm in female (n = 10), 9.7 mm in male holotype . Male genitalia ( Figs 6A–6H ). Ventrolateral sides of synsclerotized segment IX protruding anterad and round on each side in lateral aspect ( Fig. 6A ); posteroventral lobe long and rectangular in ventral aspect ( Fig. 6C ), its apex weakly bilobed in ventral aspect. Dorsal part of segment IX subtriangular, apically round in dorsal aspect ( Fig. 6B ), fused with segment X laterally ( Fig. 6A ). Segment X bilobed in dorsal aspect ( Fig. 6B ), with pair of large posterolateral setose areas ( Fig. 6A ); each ventrolateral margin sclerotized, recessed into segment IX ( Fig. 6A ). Inferior appendages each without distal segment, long and finger-like in lateral aspect ( Fig. 6A ), extending beyond apex of segment X, slightly curved upward apically; slightly convex subapicomesally, with about 10 spine-like setae ( Figs 6A–6C ). In phallotheca, long dorsal process thin, whip-like in lateral aspect ( Fig. 6D ), gradually curving posteroventrad (specimens macerated by KOH solution often strongly curved or recurved apically as in Fig. 6F ); broad basally and tapering to acute apex in dorsal aspect ( Fig. 6E ); lateral processes absent; pair of ventral processes in lateral and dorsal aspect ( Figs 6D–6F ) slender, almost straight, approximately half as long as dorsal process. Aedeagus evenly curved ventrad in lateral aspect ( Fig. 6D ); stem half-pipe-like, with pair of posterior lobes, each lobe oval in lateral aspect ( Figs 6D ) and concave mesally ( Fig. 6E ); with head approximately 1/4 as long as basal stem ( Fig. 6D ). Female genitalia ( Figs 6I–6L ). Lateral lobes of sternum VIII widely separated from each other in ventral aspect ( Fig. 6K ), each with mesal margin concave in middle. Segment IX oblique rectangular in lateral aspect ( Fig. 6I ), subpentagonal with round lateral and apical margins in dorsal aspect ( Fig. 6J ); pair of mesal lobes sclerotized, semicircular in lateral aspect ( Fig. 6I ); pair of sclerotized ribs forming wide trapezoidal lobe on vulvar scale basoventrally ( Fig. 6K ). Vulvar scale large, membranous and convex apically. Vaginal apparatus long pentagonal in dorsal aspect ( Fig. 6J ), tapering to duct of bursa copulatrix; posterodorsal part semimembranous, with complicated wrinkles, with pair of longitudinal ridges dorsally, opening of duct of spermatheca situated between ridges near middle, with dark inverted V-shaped mark dorsally, partially surrounding opening of duct of spermatheca ( Fig. 6J ). Geographic variations of male and female genitalia ( Figs 6G, 6H, 6L ). In males collected from Okayama and Hiroshima Prefectures, the posteroventral lobe of segment IX is short ( Fig. 6G ). The ventral processes of the phallotheca are approximately the same length as the dorsal process of the phallotheca in specimens collected from Hiroshima Prefecture ( Fig. 6H ). In females collected from Hiroshima Prefecture , the posterior margin of basoventral lobe on the vulvar scale is shallowly concave ( Fig. 6L ). Immature stages. Unknown. Holotype . Male (in alcohol): Takezaki , Okuizumo-cho , Shimane , 35.1693°N , 133.1751°E , alt. 761 m , 16– 28.v.2007 , M. Hayashi , Malaise trap ( KPM-NK TN00580 ). Paratypes . 10 males , 5 females (in alcohol), same data as holotype ( KPM-NK TN00590 , KPM-NK TN00600 ) . Other specimens examined . JAPAN : HONSHU: Tottori : 1 male , 2 females , Funadani-gawa , Kofu-cho , alt. 750 m , 25.v.1993 , N. Kuhara (KuN). Shimane : 25 males , 12 females , same data as holotype ( 20 males , 7 females : NK ). Okayama : 5 males , 1 female , Oosaooino , Niimi-shi , 8.v.2016 , K. Nojima ( KN ); 3 males , 1 female , Hiruzenkamifukuda , Maniwa-shi , 5.v.2016 ( KN ). Hiroshima : 1 male , 2 females , Yoshiwa , Hatsukaichi-shi , 11.v.1976 , K. Baba ( KPM ); 3 males , Hosomi-dani , Yoshiwa , Hatsukaichi-shi , 11.v.2005 , I. Mori . Etymology. The species epithet (Latin adjective, whip-like) refers to the whip-like dorsal process of the phallotheca. Distribution . Western Honshu (Chugoku District). Biology. Many adults of this species were collected in May using a Malaise trap over a small spring flow at the type locality ( Kawase and Hayashi 2010 ). Japanese name. Muchio-kimadara-shima-tobikera.