Taxonomic study of the genus Oxyethira Eaton 1873 (Trichoptera: Hydroptilidae) from Northeast Brazil: Eleven new species and distributional records De Souza, Wagner Rafael M. Santos, Allan Paulo Moreira Zootaxa 2017 4236 3 484 506 63HRL 173796 [151,272,1641,1667] Insecta Hydroptilidae Oxyethira Animalia Trichoptera 6 490 Arthropoda genus   Description. Holotype.Length 2.0 mm. General color pale brown (in alcohol). General pattern of Neotropical  Oxyethira. Sternum VII with posterior mesoventral process ( Figs. 5A, 5C). Male genitalia: Segment VIII annular, covered with setae; sternum with ogival posteromesal incision ( Fig. 5A); tergum with posterior margin produced into two rounded lobes separated by small V-shaped notch ( Fig. 5B). Segment IX retracted in segment VIII; sternum IX produced anteriorly and reaching into posterior area of segment VII, with anterior margin truncate, and with two pair of posterolateral digitiform processes; in lateral view both pairs of processes about same length, dorsal pair slightly curved caudoventrad, reaching longer posterodorsal margins of segment VIII, ventral pair straight and protruding beyond shorter posteroventral margins of segment VIII ( Fig. 5B); tergum reduced. Inferior appendages short, darkened at apex; in ventral view subrectangular, fused to sternum IX basally, and slightly divergent apically ( Fig. 5A); in lateral view completely hidden by segment VIII. Subgenital plate conspicuous; in ventral and dorsal views appearing as two lateral arms directed obliquely anterolaterad and connected posteriorly with transverse band, slightly produced caudad at posterior corners ( Figs. 5A, 5B); in lateral view lobate ( Fig. 5C). Bilobed process with short lobes, each with small apical seta ( Figs. 5A, 5B). Tergum X membranous. Phallus simple, elongate, angled left about 50°subapically and acute apically; ejaculatory duct indistinguishable ( Fig. 5D).   Remarks.  Oxyethira diplospissa  sp. nov.shares with  O. spissa( incertae sedis) some features of the male genitalia: Segment VIII with tergum produced into two rounded lobes, the inferior appendages short, with darkened apices, and the phallus apex acute and curved laterad. However, this new species can be distinguished by segment IX, which in  O. spissahas a pair of dorsal processes exceeding the posterior margin of segment VIII, whereas in the new species segment IX bears two pair of subequal processes, only the ventral one protruding beyond segment VIII. Additionally, in the new species the oblique anterolateral arms of the subgenital plate are broad, not slender as described for  O. spissa.   Etymology.The specific name is derived from the Latin word “ diplo” means double, in reference to the presence of the second pair of posterolateral processes of segment IX.   Material examined. Holotype.  BRAZIL: Alagoas: Quebrangulo,  Reserva Biológica de Pedra Talhada, Rio Cafuringaabaixo da represa, 9°15'15''S, 36°25'07''W,  20.vi.2014, APM Santos, DMTakiya, AC Domahovski& WRM Souzacols., light trap, 1 ♂( DZRJ).  Paratype.  Samedata as holotype, 1 ♂( DZRJ). 1437079632 [567,797,727,752] 2014-06-20 APM, DZRJ Reserva Biologica de Pedra Talhada & Santos, DM & AC Domahovski & Souza Brazil Quebrangulo -9.254167 Rio Cafuringa 21 -36.418613 Reserva Biologica de Pedra Talhada 9 493 1 1 Alagoas paratype 1437079649 [756,1164,803,828] DZRJ Brazil Same 9 493 1 1 Alagoas holotype