Beardius bucephalus, Pinho & Mendes & Andersen, 2013

Pinho, Luiz Carlos, Mendes, Humberto Fonseca & Andersen, Trond, 2013, Revision of Beardius Reiss et Sublette, 1985 (Diptera: Chironomidae), with the description of twenty new species, Zootaxa 3742 (1), pp. 1-78 : 26-28

Beardius bucephalus sp. n.

( Figs 30–34 )

Type material. Holotype: male, BRAZIL, Paraíba State: Mamanguape, Guaribas Biological Reserve, Rio Cabeça de Boi , 29.vii.2009, at light, A.R. Calor & L.S. Lecci ( MZSP) . Paratypes: 2 males, as holotype ( MZUFBA, ZMBN) . 1 male, Acre State: Mâncio Lima, Serra do Divisor National Park, Igarapé Amor , 18.iii.2006, at light, A.R. Calor ( INPA) .

Diagnostic characters. The species belongs in the monotypic bucephalus group. The male can be separated from all other members of the genus by the following combination of characters: basal projection of inferior volsella subquadrate, transverse; median volsella wart-like; and anal point very short, arising from rounded, posterior protrusion of tergite IX.

Etymology. From Greek bucephalus , meaning the head of the ox, referring to the type locality Rio Cabeça de Boi (“Ox Head River”).

Description

Male (n = 4, except when otherwise stated). Total length 2.85–2.98, 2.91 mm. Wing length 1.38–1.47, 1.43 mm. Total length / wing length 2.03–2.07, 2.04. Wing length / length of profemur 1.67–1.73, 1.71.

Coloration. Head and thorax stramineous; abdomen pale, with narrow, brown anterior transverse bands on tergites II–VIII. Legs stramineous.

Head ( Fig. 30 ). AR 1.36–1.47 (2), ultimate flagellomere 561–589 (2) µm long. Temporal setae 9–12, 11; not well separated in inner and outer verticals and postorbitals. Clypeus with 10–14, 12 setae. Tentorium 114–127, 121 µm long; 30–33, 31 µm wide. Stipes 121–139, 134 µm long. Palpomere lengths (in µm): 30–43, 35; 30–35, 33; 124–137, 129; 149–159, 156; 230–248 (3). Third palpomere with 2–3, 3 sensillae subapically, longest 13–20, 15 µm long.

Thorax ( Fig. 31 ). Scutal tubercle present. Antepronotum without setae. Dorsocentrals 6–7, 7; acrostichals absent; prealars 2. Scutellum with 4 setae.

Wing ( Fig. 32 ). VR 1.24–1.35, 1.30. R 4+5 with 1–2, 2 setae at apex. Brachiolum with 2 setae. Remaining veins bare.

Legs. Spur of fore tibia (including scale) 43–48, 45 µm long; spur of mid tibia (including comb) 70–80, 75 µm long; spur of hind tibia (including comb) 75–86, 80 µm long. Width at apex of fore tibia 48–59, 54 µm; of mid tibia 51–56, 54 µm; of hind tibia 54–59, 56 µm. Lengths and proportions of legs as in Table 5.

Hypopygium ( Figs 33–34 ). Anal point bluntly triangular, 8–18, 13 µm long; sitting on rounded, posterior protrusion of tergite IX. Tergite IX without setae, tergal bands absent. Laterosternite IX with 2 setae. Phallapodeme 51–68, 58 µm long. Transverse sternapodeme 40–46, 43 µm long. Gonocoxite 91–114, 106 µm long. Superior volsella digitiform, curved, 61–68, 66 µm long, with 5–9, 7 dorsal, and 4–5, 4 ventral setae, without microtrichia. Median volsella with 1–4, 3 setae, longest 15–25, 20 µm long. Inferior volsella clavate, slightly curved, 89–101, 94 µm long, with 2 apical thin setae and 6–9, 8 stout setae subapically; projection subrectangular, 38–43, 40 µm long, arising from base of volsella. Gonostylus 139–154, 147 µm long. HR 0.65–0.75, 0.72. HV 2.09–2.22, 2.15.

Female and immatures. Unknown.

Distribution. The species is collected in the Acre and Paraíba States in Brazil.

Figures

FIGURES 30–34. Beardius bucephalus sp. n., male. 30—head; 31—thorax; 32—wing; 33—anal point and tergite IX and dorsal aspect of left gonocoxite and gonostylus; 34—hypopygium with anal point and tergite IX removed, left dorsal aspect, right ventral aspect.