Arthropeina diadelothorax Fachin & Amorim, 2014, sp. nov.

Arthropeina diadelothorax, sp. nov.

(Figs. 4, 27–31, 62, 70–71, 80, 86)

Diagnosis (female). Body color yellowish (Figs. 80, 86). Scutum mostly reddish yellow, with two quadrangular black spots on prescutum, two triangular black spots on postscutum, and a medial, wider black band extending from anterior margin of scutum to scutellum basally (Fig. 62); anepisternum anteriorly with a black spot; laterotergite and mediotergite dark brown to black. Projection of posterior margin of genital fork long, abruptly narrowing towards apex (Figs. 27–29).

Material examined. HOLOTYPE, ♀, BRAZIL, Rondônia, Cacaulândia, Trilha da Cachoeira Jamari, 10º13’28,8”S 63º13’49”W, Malaise 27, 10.ii–20.v.2012, Lamas, Nihei & eq. col. (MZUSP). P ARATYPES: 1 ♀, (antennae and left wing slide–mounted), 04.xi.2011 – 10.ii.2012, same locality as holotype (MZUSP).

Description. Female. Length: body, 5.0–6.0 mm; wing, 5.0–6.0 mm. Head. Vertex yellowish, setation yellow. Upper frons yellowish. Flagellomeres l–3 dark brown on outer margin, pale ventrally on inner margin; flagellomeres 4–8 dark brown to black; eighth flagellomere more than three times the length of seventh (Fig. 4). Palpus (Fig. 71) pale, elongate; basal segment cylindrical, two times its width; apical segment oval, 1.6 times its width, twice length of basal segment; both with pale hairs. Thorax (Fig. 62). Postpronotal lobes pale, with a narrow blackish notopleural strip. Scutum reddish yellow, with two more or less quadrate black spots on prescutum, two triangular black spots on postscutum, and a medial wider black band (wider at anterior and posterior ends) extending from anterior margin of scutum to base of scutellum; scutellum black basally, with short yellow pilosity. Pleura pale, except anepisternum anteriorly with a large medial black spot; laterotergite and mediotergite dark brown to black. Legs. Mostly yellow, except for tarsomeres vaguely brownish, hind coxae and trochanters dark brown, mid femora at extreme base and ventrally at apex brownish, hind femora at extreme base as well as two-thirds of hind tibiae dark brown. Wing as in Fig. 70. Halter reddish yellow. Abdomen. Yellowish with black transverse bands on tergites except on tergite 1; black color slightly decreasing in width from tergites 2 to 4; tergites 5–7 entirely black; sternites weakly sclerotized. Female genitalia (Figs. 27–31). Tergite 8 wide, more or less quadrate, rounded anteriorly, slightly flattened medially at basal margin. Sternite 8 roughly quadrate (Fig.

30), weakly sclerotized, narrowing towards apex; gonapophyses unsclerotized, with short and wide lobes. Tergite 9 wider distally (Fig. 28). Genital fork with anterior arm rounded (Figs. 27–29), clearly more slender than posterior arm; posterolateral processes rounded; membranous lobes of genital fork more rounded distally, with basal half more slender than distal half; projection of posterior margin long, narrow, acuminate; margin between posterior projection with a moderately profound medial incision; genital opening small, oval, placed basally on posterior margin, bursa densely covered with microtrichia. Cercus with segment 1 more than twice length of segment 2.

Male. Unknown.

Etymology. The species name is feminine, and the specific epithet comes from the Greek roots diadelos, meaning distinctive, distinguishable, and thorax, as a reference to the conspicuous color pattern of the scutum of the species.

Geographic distribution. Northern Brazil (State of Rondônia) (Fig. 92).

Comments. The laterotergite of this species may be entirely or only partly black. In addition, on the abdomen, the black color of tergites 5–7 sometimes does not cover the entire surface.