Rhyacopsyche yungas Rocha & Santos & Nessimian 2023, sp. nov.

Rhyacopsyche yungas sp. nov.

Figures 16, 17

Description, male. Head. Wider than long, frontal margin convex, ocellar setose warts subtriangular, posterior setose warts subtriangular with longitudinal length about 2/3 transverse width (Fig. 16A). Antennae each 33-articulated, scape about 2x as long as wide, median flagellomeres each about 1.5x as long as wide with slender tapered setae scattered over entire flagellomere; apical flagellomere conical.

Thorax. Metascutellum pentagonal (Fig. 16B). Length of each forewing: holotype 3.5 mm; paratype 3.4 mm. Forewings elliptical, hind wings tapering from basal third, acute apically. Forewings each with jugal lobe.

Pregenital abdominal segments. Segments V, VI with no modifications. Segment VII with ventromesal process triangular.

Genitalia. Segment IX partially retracted within segment VIII, open dorsally; in lateral view, trapezoidal, anterior margin oblique, posterior margin nearly straight, posterolaterally produced and truncate below mid-height (Fig. 17A); in ventral view, anterior margin excavated mesally, U-shaped, posterior margin shallowly excavated mesally (Fig. 17C). Pair of dorsolateral lobes of segment IX elongate, about as long as anterior portion of segment, bearing fine dorsal setae; in dorsal view, fused basally, parallel and almost touching beyond basal fusion, bearing ventral peg-like setae subapically, lobes blunt apically (Fig. 17B). Inferior appendages elongate, slightly longer than dorsolateral lobes of segment IX, widely separated basally and apically; in lateral view, enlarging apically, dorsal margin produced into round lobe at mid-length, apex round bearing long, dorsal, peg-like setae (Fig. 17A). Preanal appendages absent. Pair of subgenital processes ventrally fused into small subrectangular plate (Fig. 17C). Tergum X membranous, apex slightly sclerotized, upturned (Fig. 17A). Phallus tubular, slender except at extreme base, elongate, slightly curved, with thin membranous sheath surrounding phallus subapically, ejaculatory duct long slightly sclerotized, not protruding apically (Fig. 17D).

Remarks. This new species is quite different from all other species of Rhyacopsyche by having inferior appendages in lateral view enlarging apically and with their dorsal margins produced at mid-length. Rhyacopsyche yungas sp. nov. is somewhat similar to R. benwa Wasmund & Holzenthal 2007 due to the long dorsolateral lobes of segment IX fused basally, almost touching beyond their basal fusion and bearing several ventral peglike setae subapically. The presence of a long paramere in the phallus of R. benwa easily distinguishes this species from R. yungas sp. nov. that lacks such a paramere. This new species can also be diagnosed by having a long and slender phallus, which lacks processes or sclerites commonly seen in other species of this genus.

Material examined. Holotype. Peru: Cusco: Quincemil, 3 km E, 13º13’03”S 70º43’40”W, 633 m, Malaise, 20.viii.2012, RR Cavichioli, JA Rafael, APM Santos, DM Takiya leg., male (MUSM). Paratypes. Same data as holotype, 1 male (DZRJ).

Etymology. Yungas is an Aymara word meaning warm lands. It is used to name the ecoregion located between the eastern slopes of the Andes Mountains and the eastern forests of the Amazon, and where the holotype was collected. The species epithet is not a Latin or latinized word; therefore, it is to be treated as indeclinable and does not need to agree in gender with its generic name.