Chaethippus maculatus, Riccardi, 2020

Riccardi, Paula Raile, 2020, Taxonomic revision of the genus Chaethippus Duda, 1930 (Diptera: Chloropidae) with the description of four species, Zootaxa 4802 (1), pp. 129-140 : 135-136

Chaethippus maculatus sp. nov.

( figs. 20–24 )

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Material examined. Holotype ♀ BRAZIL, Rondônia, Campo Novo, Fazenda Amorim , 10°40.128’S 63°29.004’W, Malaise trap, 6–10.xii.2011, Amorim, Ament & Riccardi leg. [ MZUSP].

Diagnosis. Tibial spur well developed; one strong vibrissa; two pairs of prescutellar setae; anepisternum bare, with a black spot; fore coxa with three long setae anteriorly.

Description. Body length, 2.95 mm. Wing length, 2.4 mm.

Head ( figs 20–21 ). Wider than long dorsally and higher than long in profile, entirely yellow except for black ocellar tubercle and a black spot on the ocellar triangle. Head and thoracic setae black. Frons about as long as wide, lateral margins subparallel, front margin straight. Ocellar triangle pruinose, extending to three quarters length of frons, posterior margin two thirds width of frons, lateral margins slightly concave, apex acute; macula blackish. Eye oval, long axis slightly oblique with short, dense pubescence. Face longer than high; facial carina width as wide as aristal base, almost reaching the frontoclypeal suture; antenna yellow, postpedicel reniform, as high as long, entirely yellow; arista yellowish on the basal 1/3 and black apically, with short pubescence, about two times as long as postpedicel; gena as wide as length of postpedicel, rather curved inwards; one vibrissa; occiput dark yellow, ventrally with a M-shaped black mark; proboscis yellow; palpus yellow, small, equal in length to antenna, slightly curved upwards, with brown setulae; oral margin not protruding; clypeus yellow. Thorax ( fig. 20 ). Scutum quadrate, yellow, with six black orangish stripes; scutum densely pruinose with dark setulae; one posterior dorsocentral seta developed, longer than outer vertical seta; a row of four prescutellar setae; postpronotal lobe yellow with one long seta equal to notopleurals and prescutellars; postalar seta developed, about as long as dorsocentral seta. Pleuron bare, yellow, a black spot along the anterior edge of anepisternum. Scutellum yellow pruinose, convex on the disc, with black setulae, wider than long, slightly triangular apically; apical scutellar seta with separation equal to that of posterior ocelli and as long as length of scutellum; two pairs of lateral setae developed, as long as dorsocentrals; post-scutellum orange-yellow, shining. Wing. Hyaline with pale brown veins covered in sparse brown microtrichia; costal sections 1–4: 8: 10.5: 6.5: 3.5; veins R 4+5 and M 1 almost parallel; distance between r-m and dm-m six times length of r-m. Halter pale yellow. Legs ( fig. 20 ). Yellow, apical tarsomeres darkened; femoral organ unknown; hind tibia with a long, curved preapical spur; posterior tibial organ short and oval, occupying less than half of tibia length, yellow. Abdomen ( fig. 20 ). As in the generic diagnosis. Male terminalia. Unknown. Female terminalia ( fig. 22–24 ). Segments 6–8 narrow; epiproct bare, with a pair of setae; hypoproct pilose; cerci brown, long and narrow, with short setae.

Etymology. The specific epithet “ maculatus ” is a Latin adjective, meaning spotted. It refers to the dark macula on the anepisternum.

Remarks. The description of the species Chaethippus maculatus relies only on females and the female terminalia between the species of this genus is not variable. However, the combination of scutum, fore coxa and pleuron pilosity with number of vibrissae and presence/absence of hind tibial spur has proven to be effective for species recognition. In this sense, the absence of males does not compromise the correct identification of C. maculatus .

Figures

FIGURES 20–24. Chaethippus maculatus sp.nov. holotype. 20, habitus (scale bar 1 mm). 21, head in dorsal view. 22, abdome ventral (scale bar 0.1 mm). 23, female terminalia, dorsal. 24, female terminalia, ventral. Abbreviations: cer, cercus; epi, epiproct; hypo, hypoproct.