Alterosa ruschii, Dumas, Leandro Lourenço & Nessimian, Jorge Luiz, 2013

Dumas, Leandro Lourenço & Nessimian, Jorge Luiz, 2013, New species of the caddisfly genus Alterosa Blahnik 2005 (Trichoptera: Philopotamidae: Philopotaminae) from Brazil, Zootaxa 3609 (1) : -

Alterosa ruschii , new species

Fig. 11 A–D

Alterosa ruschii sp. nov. probably belongs to the A. sanctipauli Group, as defined by Blahnik (2005), by sharing a basal rounded protuberance on tergum X, with cuticle scabrously developed. The new species is most similar to A. bocainae Blahnik 2005 and A. fimbriata Blahnik 2005 , with which it shares short, broad intermediate appendages armed with coarse setae. However, A. ruschii sp. nov. has intermediate appendages branched basally and very small preanal appendages, whereas A. bocainae and A. fimbriata have intermediate appendages not branched and well developed preanal appendages. Additionally, the apicodorsal crest-like Y-shaped expansion of tergum X is unique among species of Alterosa .

Adult. Color (in alcohol) dark brown; legs, palps, and antennae light brown, wing pattern not discernible. Male forewings each 5.8–6.1 mm (n=2).

Male genitalia. Tergum VIII with posteromesal margin moderately emarginate, emargination V-shaped and extending no more than halfway to anterior margin. Sternum IX with anterolateral margin weakly rounded, subtruncate; posteroventral margin moderately produced, forming broadly rounded expansion ( Fig. 11 A). Tergum IX greatly reduced, membranous or fused to base of tergum X ( Fig. 11 B). Tergum X subtriangular in dorsal view, tapered from base; tergum basolaterally with small area of scabrous cuticle and with thumb-like protuberance covered by small spines; subapically with dorsal crest-like Y-shaped expansion (2 branches directed anterad and 1 directed posterad and bearing two small spines); apex sensillate, rounded as viewed dorsally, subtruncate and moderately enlarged in lateral view ( Figs. 11 A, 11B). Intermediate appendages heavily sclerotized, branched basally; mesal branch short, rod-like, blunt and with small, coarse setae apically; lateral branch lobe-like, laterally compressed, covered by spine-like setae, subacute apically in dorsal view, apex greatly enlarged and rounded, with small ventrolateral projection as viewed laterally ( Figs. 11 A, 11B). Preanal appendages very short, much shorter than intermediate appendages, club-like, slightly constricted basally, not greatly modified, with scant small setae, each with small subapicoventral projection bearing small terminal apical seta as viewed laterally, its apex rounded in dorsal view and blunt in lateral view ( Figs. 11 A, 11B). Inferior appendages elongate, linear, slightly flattened on mesal surface, setose; 1st article elongate, approximately 4 times as long as wide in lateral view and longer than tergum X; 2nd article nearly half length of 1st article, base as wide as apex of 1st article, slightly enlarged apically and with small pad of short, stiff apicomesal setae ( Figs. 11 A, 11C). Phallobase tubular, short, scarcely curved ventrad; endotheca with no evident spines or phallotremal sclerites ( Fig. 11 D).

Holotype male: BRAZIL: Espírito Santo: Santa Teresa, Estação Biológica de Santa Lúcia, Córrego Bonito, above Cachoeira Heloísa Torres, 19°58’25.9”S, 40°31’46.3”W, el. 685 m, 03.iv.2011, LL Dumas & GA Jardim leg. (DZRJ 3493).

Paratypes: Same data as holotype, 1 male (DZRJ 3494).

Distribution: Brazil (Espírito Santo state).

Etymology: This species is named ruschii in memory of Augusto Ruschi, a Brazilian naturalist involved in the conservation of natural areas in the state of Espírito Santo, including Estação Biológica de Santa Lúcia where the type specimens were collected.

Figures

FIGURE 11. Alterosa ruschii, new species, male genitalia. 11 A, left lateral view; 11 B, dorsal view (right lateral branch of intermediate appendage omitted); 11 C, left inferior appendage, dorsal view; 11 D, phallic apparatus, left lateral view.