New Orthalicidae (Mollusca, Gastropoda) from Venezuelan Guayana: unravelling secrets from the Lost World Author Breure, Abraham S. H. text Zootaxa 2009 2065 25 50 journal article 10.5281/zenodo.186920 695e995e-3a9a-41b8-bafa-ed8366b37ef4 1175-5326 186920 Plekocheilus (Eurytus) fusitorsus ( Oberwimmer, 1931 ) ( Figs 4 H─L, 9I ) Eurytus fusitorsus Oberwimmer, 1931 : 190 , figs 1, 4. Type locality: Venezuela , Territorium Amazonas, Río Padamo; holotype SMF 5142. Material. Venezuela , Estado Bolívar, Cerro Guaiquinima, along Río Paragua , 1500 m , J.A. Steyermark leg., 1978, in wooded portion of moist dwarf forest ( FMNH 198500/1); Estado Amazonas, Río Padamo ( SMF 5142/ holotype ). Shell dimensions are given Table 1 . Remarks. This species is characterized by dark, undulating stripes on the last whorl bordered by a yellowish ‘shadow’ and a fine granulation of dotted granules (Fig. 9I ). A subadult specimen from Cerro Guaiquinima (FMNH 198500) is tentatively referred to this species. It is characterized by the same colour pattern as observed in the holotype , but has oblong granules on the upper part of the last whorl, giving an impression of spiral incisions in between. The type locality is a river basin that covers 10.280 square km and drains the northwestern slopes of the Sierra Parima on the east-central border of Estado Amazonas in Venezuela and Estado Roraima in Brazil ( Huber 1995a ). Río Padamo is slightly east of Cerro Duida [ type locality of Plekocheilus (Eurytus) tatei Haas, 1955 ] and Cerro Marahuaka [ type locality of P. (E.) gibber ( Oberwimmer, 1931 ) ]. The headwaters of Río Padamo are on Cerro Kikirisha, slightly over 1000 m , but along its course elevations of 500 m or less prevail. Since the exact type locality is unknown, it cannot be excluded a priori that P. (E.) fusitorsus also occurs in the lowland. This species might also be expected at intermediate localities in between the two occurrences, e.g. in the Jaua-Sarisariñama massif.