Smittia

Saether, Ole A. & Andersen, Trond, 2011, Chironomidae from Gough, Nightingale and Tristan da Cunha islands, Zootaxa 2915, pp. 1-19 : 9-10

Smittia sp.

( Figs 11–16 )

Material examined. TRISTAN DA CUNHA: Site 7, on rim west of patches, above Molly Gulch, below Dailies Hill, 37°108'44"S, 12°326'53"W, Blechnum palmiforme -grassland mix, 2270 ft., Malaise trap, 15–21.ii.2005, 1 female, C. Hänel ( ZMBN).

Diagnostic characters. This female is typical for the genus in most details, but can perhaps be identified by details of the genitalia and the chaetotaxy.

Description. Female (n = 1). Total length 1.63 mm. Wing length 0.93 mm. Total length / wing length 1.76. Wing length / length of profemur 3.27.

Coloration. Fully brown.

Head. AR 0.44. Lengths (in µm) of flagellomeres: 51, 45, 43, 43, 79. Apical antennal seta 68 µm long. Temporal setae 3 including 1 inner vertical and 2 outer verticals. Clypeus with 8 setae. Tentorium 86 µm long, 11 µm wide. Stipes 83 µm long, 30 µm wide. Palpomere lengths (in µm): 19, 26, 53, 58, 75. Third palpomere apparently without sensilla clavata. Coronal suture 26 µm long.

Thorax. Median antepronotal lobes well developed, no lateral setae on antepronotum. Dorsocentrals 12, acrostichals not measurable, prealars 6, supraalar seta 1. Scutellum with 4 setae.

Wing ( Fig. 11 ). VR 1.26. Anal lobe reduced. Costal extension 101 µm long. R4+5 ending distal to apex of M3+4, Cu1 sinuate. Brachiolum with 1 seta, costa between FR and apex of R4+5 with 45 non-marginal setae, costal extension with 15 non-marginal setae, R with 9, R1 with 6, R4+5 with 12 setae, other veins bare.

Legs. Spur of fore tibia 28 µm long, spurs of mid tibia both 17 µm long, of hind tibia 38 µm and 19 µm long. Width at apex of fore and mid tibia both 28 µm, of hind tibia 34 µm. Comb of 11 setae, 19–23 µm long. Lengths and proportions of legs as in Table 3.

fe ti ta1 ta2 ta3 ta4 ta5 LR BV SV BR p1 284 321 161 95 66 43 38 0.50 3.18 3. 76 2.0 p2 312 340 128 76 61 38 33 0.38 3.75 5. 11 2.2 p3 340 383 194 109 95 47 38 0.51 3.18 3.73 2.7 Abdomen. Number of setae on tergites I–VIII as: 4, 10, 14, 16, 14, 14, 15, 12. Number of setae on sternites I– VIII as: 0, 0, 2, 2, 4, 6, 8, 6.

Genitalia ( Figs 12–16 ). Gonocoxite low, rounded, with 4 setae. Tergite IX not divided, but slightly emarginated, with altogether 10 setae. Ventrolateral lobe relatively narrow, not covering dorsomesal lobe. Cercus 49 µm long. Segment X rounded posterolaterally. Seminal capsule about 83 µm long, about 56 µm wide, neck sclerotized for about 4 µm, microtrichia not observed, spermathecal ducts with loop, without bulbs before common opening. Notum 90 µm long.

Remarks. The species probably is parthenogenetic and endemic, but as only a single specimen was found on Tristan, it is better not named here. The genus is in need of revision and this female is rather typical.

Figures

FIGURES 11 – 16. Smittia sp., female. 11 — wing; 12 — genitalia, ventral view; 13 — genitalia, dorsal view; 14 — ventrolateral lobe; 15 — dorsomesal lobe; 16 — apodeme lobe.