Metrichia takiya, Rocha & Santos & Nessimian, 2023

Rocha, Isabela Cristina, Santos, Allan Paulo Moreira & Nessimian, Jorge Luiz, 2023, Taxonomic diversity of Ochrotrichiinae (Trichoptera: Hydroptilidae) from Peru with the description of ten new species, a new distributional record, and an updated checklist, Zootaxa 5353 (4), pp. 301-331 : 318-319

Metrichia takiya sp. nov.

Figure 11

Description, male. Head. Wider than long, frontal margin convex, ocellar setose warts subtriangular, posterior setose warts transversely ellipsoidal with longitudinal length about 1/3 transverse width. Antennae each 18-articulated, scape about 2x as long as wide, median flagellomeres each almost as long as wide and with blunt setae forming basal row, apical flagellomere with digitate apical process.

Thorax. Metascutellum triangular. Length of each forewing: holotype 1.9 mm. Wings strongly tapered from near bases, acute apically. Forewings each with jugal lobe.

Genitalia. Segment VIII shorter ventrally than dorsally ( Fig. 11A ). Segment IX reduced dorsally, partially retracted within segment VIII, covered with long flattened setae; in lateral view, twice as long as wide, tapering anteriorly, posterior margin oblique ( Fig. 11A ); in ventral view, anterior margin round, posterior margin widely excavated mesally ( Fig. 11C ). Inferior appendages subrectangular in lateral view, half as long as segment IX, covered with small setae; in ventral view, each with apex slightly excavated and bearing mesal triangular projection on inner face ( Fig. 11C ). Dorsal hooks slightly longer than inferior appendages, angled ventrad apically, each with small, round, dorsal projection on basal third ( Fig. 11A ). Preanal appendages elongate, slightly more than half as long as inferior appendages, covered apically with flattened setae ( Fig. 11A ). Subgenital processes absent. Tergum X membranous, truncate in dorsal view, covered dorsally with microsetae ( Fig. 11B ). Phallus tubular, short, base broad, two large spines subapically arising at about same level; apex slightly sclerotized, folded; internal sclerites absent; ejaculatory duct slightly sclerotized, straight, not protruding apically (Figs, 11D, 11E).

Remarks. As in M. takiya sp. nov., M. adamsae , M. malada , and M. peruana sp. nov., each inferior appendage has an apical triangular projection and dorsal hooks are long, but the larger preanal appendages and arrangement of the spines of the phallus easily distinguish the new species from the others. Flint (1991) observed elongate pouches between segments V and VI of M. malada and tergum VI darkened with the posterior margin bearing very small, lateral pockets. Unfortunately, the abdomen of M. takiya sp. nov. was damaged during preparation, but tergum VI is probably darkened and bearing the same lateral pockets observed in M. malada , as in most new Metrichia species described here.

Material examined. Holotype. Peru: Cusco: Quincemil, 19 km W, Río Araza, Puente Saucipata , 13º20’10”S 70º50’57”W, 874 m, Malaise, 23–31.viii.2012, RR Cavichioli, JA Rafael, APM Santos, DM Takiya leg., male ( MUSM).

Etymology. Named in honor of the Brazilian entomologist Dr Daniela Takiya, who supervised many entomology students from Brazil and other South American countries and described many species of caddisflies. She is also one of the collectors of the material studied in this manuscript.

Figures

FIGURE 11. Metrichia takiya sp. nov., male genitalia. 11A, left lateral; 11B, dorsal; 11C, ventral; 11D, phallus, dorsal; 11E, phallus, left lateral.