A revision of the Neotropical caddisfly genus Rhyacopsyche, with the description of 13 new species (Trichoptera: Hydroptilidae) Author Wasmund, Anne M. Author Holzenthal, Ralph W. text Zootaxa 2007 1634 1 59 journal article 10.5281/zenodo.179477 3ff8b316-c411-4d6b-af4c-e7bb7a663759 1175-5326 179477 Rhyacopsyche matthiasi Flint Fig. 19 Rhyacopsyche matthiasi Flint, 1991 :61 [ Type locality: Colombia , Dpto. Antioquia, Urrao; NMNH; male]. This species bears some resemblance to R. colei with regard to the midlateral process of segment IX and the presence of plumose setae on the inferior appendage. In addition to R. matthiasi , 3 other species, R. hagenii , R. dikrosa , and R. colei , bear a process along the posterior margin of segment IX; however, this is the only species with an articulation of that process. The apex of this process, more correctly regarded as an appendage, is also unique with its 4 apicomedial ridges. Adult (male n=2). Forewing length 3.4, 3.8 mm . Color of head dark brown, antennae light brown, legs cream, wings mottled medium and dark brown. Sternum VII with apicomesal point. Male genitalia. Abdominal segment IX with no apparent setae, anterior margin nearly straight, produced anteroventrally; sternum IX, in lateral view, with posterior margin slightly rounded, with connecting membrane to inferior appendage; posterior margin produced into midlateral appendage with 4 small apicomedial ridges; dorsolateral lobe of segment IX slightly produced, in dorsal view trianguloid, widely separated, apex bearing several thin setae. Tergum X elongate, with rounded, apicolateral lobes. Intermediate appendage not evident. Inferior appendage elongate, trianguloid, heavily setose, bearing several thick, plumose setae. Phallus base inflated, membranous sheath absent; central tubule with small apical hook; apex of lateral process lanceolate. Material examined. VENEZUELA : Barinas: Parque Nacional Sierra Nevada, Rio Sinigüis at Tres Quebradas, 08°31’26”N , 070°53’46”W , 1900 m , 19.iii.1997 , Holzenthal — 1 male ( UMSP ); Merida: Laguna de Mucubaji, Paramos zone, 3300 m , site 3, rocky stream below lake, 10.vii.1991 , G S Vick — 1 male ( NMNH ). Distribution. Colombia .