Labrundinia costaricae Silva

Silva, Fabio Laurindo Da, Fonseca-Gessner, Alaide Aparecida & Ekrem, Torbjørn, 2014, A taxonomic revision of genus Labrundinia Fittkau, 1962 (Diptera: Chironomidae: Tanypodinae), Zootaxa 3769 (1), pp. 1-185 : 29-31

Labrundinia costaricae Silva sp. n.

( Fig. 11 )

Material examined. Type material: Holotype male, Costa Rica: Puntarenas, Osa, Riyito river, i.1991, W. Riss ( ZSM). 2 Paratypes: 2 males, same data as holotype ( ZSM).

Etymology. The name refers to Costa Rica where the species was collected.

Diagnostic characters. Labrundinia costaricae sp. n. differs from other Labrundinia species by the combination of the following characters. Adult male: abdominal tergite I pale, T II with divided brown transverse band near proximal margin, T IV with a narrow brown transverse band near proximal margin, T III, T V–VIII completely brown; hypopygium pale, sternapodeme with distinct anterior process.

Description. Adult male (n = 3 unless otherwise stated)

Size. Total length 1.9–2.0 mm. Wing length 0.9–1.0 mm. Total length/wing length 1.77–2.01. Wing length/ profemur length 2.58–2.87.

Coloration. Head brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax brown with dark scutum. Wing membrane transparent without any marking. Legs brown. Femur I pale brown with apex brown, Fe II–III brown. Tibia I with apex brown, Ti II–III brown. Tarsomeres 1–5 brown. Abdominal tergite I pale, T II with divided brown transverse band near proximal margin, T IV with a narrow brown transverse band near proximal margin, T III, V–VIII completely brown; hypopygium pale ( Fig. 11L ).

Head ( Figs 11A–E ). Temporal setae 10, uniserial ( Fig. 11B ). Eye ratio 0.90–0.97 (2). Tentorium ( Fig. 11C ) 118(1) Μm long. Clypeus 73–83 Μm long, 62–77 Μm wide at largest part, bearing 15–17 setae. Cibarial pump 154– 165 Μm long ( Fig. 11D ), with anterior margin concave. Lengths of palpomeres 1–5 (in Μm): 32–38 (2); 47–50 (2); 88–116 (2); 117–126 (2); 199 (1). Antennal flagellum 585–608 Μm long, diameter of pedicel 99–101 Μm, apical setae single ( Fig. 11E ), AR 0.78–0.85.

Thorax. Antepronotum with 3 lateral setae. Acrostichals 44–46, biserial, diverging evenly posteriorly, starting close to antepronotum and almost reaching scutellum; dorsocentrals 20–22, irregularly biserial; prealars 9–11; supraalars 2. Anapleural suture ratio 0.35–0.45. Scutellum with transverse row of 6–7 setae and group of numerous fine anterior setae.

Wing ( Fig. 11F ). Width 0.3 mm. Costa 0.8–0.9 mm long. R2+3 present. VR 0.75–0.78. WW 0.28–0.32. Brachiolum with 2 setae. Squama setiferous.

Legs ( Figs 11G–K ). Fore leg: width at apex of tibia 30–32 Μm ( Fig. 11G ), tibia with single, apical and pectinate spur 15–16 Μm long ( Fig. 11H ), with three lateral teeth and two preapical setae; ta1-4 each with two preapical pseudospurs. Mid leg: width at apex of tibia 31–35 Μm long ( Fig. 11I ), tibia with single, apical and pectinate spur 16–20 Μm long with three lateral teeth ( Fig. 11J ) and two preapical setae; ta1-4 without any preapical pseudospurs. Hind leg: width at apex of tibia 37–40 Μm long ( Fig. 11K ), tibia without spur; comb with 5 bristles; ta1-4 without any preapical pseudospurs. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 8.

fe ti ta1 ta2 ta3

p1 359–399 369–444 227–256 167–191 103–113 p2 526–553 382–422 – – –

p3 434–488 531–582 – – –

ta4 ta5 LR BV SV

p1 78–93 55–57 0.59–0.61 2.35–2.36 3.14–3.21 p2 – – – – –

p3 – – – – – Hypopygium ( Fig. 11M ). Tergite IX arched, with 10–11 (2) posterior setae. Membranous anal point rounded, apical edge convex. Phallapodeme 39–40 (2) Μm long. Sternapodeme with distinct anterior process. Gonocoxite cylindrical, 84–91 Μm long, 38–43 Μm wide, with slightly concave inner margin. GcR 2.10–2.21 (2). Gonostylus simple and slender, 65–68 Μm long; megaseta 9–11 Μm long. HR 1.25–1.35. HV 2.82–2.89.

Adult female, pupa and larva. Unknown.

Remarks. Adult males of Labrundinia costaricae may be distinguished from those of the related species L. fosteri , L. meta , L. nathani , L. panamensis and L. nicaguarensis by the divided brown transverse band near proximal margin of T II, a narrow brown transverse band near proximal margin of T IV and a completely brown T V. Labrundinia costaricae has been recorded only from its type locality in Costa Rica. The immature stages and their habitat remain unknown.

Figures

FIGURES 11 A – M. Labrundinia costaricae Silva sp. n., adult male. A. Head, frontal view. B. Temporal setae. C. Tentorium. D. Cibarial pump. E. Apex of antenna. F. Wing. G. Apex of fore tibia. H. Fore tibial spur. I. Apex of mid tibia. J. Mid tibial spur. K. Apex of hind tibia with comb. L. Abdominal coloration pattern, dorsal aspect. M. Hypopygium, left: ventral aspect, right: dorsal aspect.