Gravatamberus apicalus, Mendes & Andersen, 2008

Mendes, Humberto Fonseca & Andersen, Trond, 2008, A review of Antillocladius Saether and Litocladius Mendes, Andersen et Saether, with the description of two new Neotropical genera (Diptera, Chironomidae, Orthocladiinae), Zootaxa 1887 (1), pp. 1-75 : 43-45

Gravatamberus apicalus sp. n.

( Figs 43–47 ).

Type material: Holotype male, VENEZUELA: Aragua: Parque Nacional Henri Pittier, Rancho Grande , 10º21.047’N, 67º41.198’W, approximately 1000 m a.s.l., 16–18.ix.1999, sweep net & light trap, rainforest, T. Andersen ( MIZA) . Paratype: 1 male, as holotype ( ZMBN) .

Diagnostic characters: The species can be separated from all other members of the genus by having less than 10 setae in cell m proximal to RM; Sc with 0–1 seta; costal extension 147–154 µm long, ending close to the wing tip; and AR 0.84–0.88.

Etymology: From Latin apicalus , meaning apex, referring to the long costal extension nearly reaching the wing tip.

Male (n = 1–2). Total length 1.61–1.64 mm. Wing length 1.01–1.05 mm. Total length / wing length 1.56– 1.59. Wing length / length of profemur 2.50–2.65. Coloration brown, thorax dark brown without distinct pattern.

Head. AR 0.84–0.88. Ultimate flagellomere 248–270 µm long, stout subapical seta 29–54 µm long. Temporal setae 8, including 3–4 inner verticals, 1–2 outer verticals, and 3 postorbitals. Clypeus with 13–16 setae. Tentorium, stipes, and cibarial pump as in Figure 43 . Tentorium 73–91 µm long, 16–20 µm wide. Stipes 86– 93 µm long, 32–41 µm wide. Palp segment lengths (in µm): 14–16, 23–25, 57–59, 73–77, fifth segment not measurable. Third palpomere with 2 sensilla clavata subapically, longest 9 µm long.

Thorax ( Fig. 44 ). Antepronotum with 1–2 setae. Dorsocentrals 12–15; acrostichals 12–14, all scalpellate; prealars 5–6, extended anteriorly; supraalar 1. Scutellum with 2 setae.

Wing ( Fig. 45 ). VR 1.41. C extension 147–154 µm long. Brachiolum with 1–2 setae, Sc with 0–1 seta, C extension with 15–17 non-marginal setae, R with 12–13 setae, R 1 with 13 setae, R 4+5 with 12 setae, M 1+2 with 29–35 setae, M 3+4 with 13–16 setae, Cu with 10–12 setae, Cu 1 with 8–10 setae, PCu with 9–10 setae, An with 10–14 setae. Cell m with 1–4 setae, r 4+5 with 100–200 setae, m 1+2 with 100–150 setae, m 3+4 with 26–43 setae, cu with 5–19 setae, and an with 18–36 setae.

Legs. Spur of foretibia 27–29 µm long, spurs of midtibia 29–34 µm and 14–18 µm long, spurs of hind tibia 36–39 µm and 16–18 µm long. Width at apex of foretibia 23 µm, of midtibia 23 µm, of hind tibia 29 µm. Comb with 9–11 setae, longest 34–36 µm, shortest 20 µm long. Lengths and proportions of legs as in Table 8.

Hypopygium ( Figs 46–47 ). Tergite IX with 2 setae, laterosternite IX with 5–6 setae. Phallapodeme 52–54 µm long, transverse sternapodeme 59–63 µm long. Gonocoxite 116 µm long. Gonostylus 59 µm long, megaseta 4 µm long. HR 1.96, HV 2.73–2.78.

Biology and distribution: This species is known only from the type locality in the coastal mountain range in Venezuela, where it was collected in an old rainforest reserve at about 1000 m altitude .

Figures

FIGURES 43–47. Gravatamberus apicalus sp. n., male. 43—tentorium, stipes, and cibarial pump; 44—thorax; 45— wing; 46—anal point and tergite IX and dorsal aspect of left gonocoxite and gonostylus; 47—hypopygium with anal point and tergite IX removed, dorsal aspect to the left and ventral aspect to the right.