Hydrosmittia brevicornis (Strenzke) Ferrington Jr & Saether, 2011

Ferrington Jr, Leonard C. & Saether, Ole A., 2011, A revision of the genera Pseudosmittia Edwards, 1932, Allocladius Kieffer, 1913, and Hydrosmittia gen. n. (Diptera: Chironomidae, Orthocladiinae) 2849, Zootaxa 2849 (1), pp. 1-314 : 107-109

Hydrosmittia brevicornis (Strenzke) comb. n.

( Fig. 35 )

Pseudosmittia brevicornis Strenzke, 1950: 281 .

Material examined: AUSTRIA: Lower Austria, Lunz, Untersee , submerged moss on stones, holotype male, 1 pupal exuviae, 15.v.1941, K. Strenzke, 1 pupal exuviae, as holotype except 30.iv.1941 ( NMS) . GERMANY: Niedersachsen, Upjever. Nr. 1695b, no other data (GP 617–GP620)( NMS) .

Diagnostic characters: The low AR (0.15) together with the apical upturned gonostylus will separate the male imago from other species of the group. The pupa has anal macrosetae, no frontal warts, nearly smooth frontal apotome and clear abdomen.

Male imago (n = 1)

Total length 2.57 mm. Wing length 0.95 mm. Total length/wing length 2.71. Wing length/length of profemur 3.52. Coloration dark brown.

Head. AR 0.15. Terminal flagellomere 57 µm long. Temporal setae apparently consisting only of 3 outer verticals. Clypeus with 5 setae. Tentorium length not measurable, 16 µm wide. Stipes 75 µm long, 23 µm wide. Palpomere lengths (in µm): 21, 37, 57, 58, 69. Third palpomere with 1 relatively long, scalpellate sensillum clavatum.

Thorax ( Fig. 35 B ). Antepronotum with well developed median lobes and 1 lateral setae. Dorsocentrals 5, acrostichals 2, prealars 3, supraalar seta absent. Scutellum with 4 setae.

Wing ( Fig. 35 A ). VR 1.51. Anal lobe not projecting, but wing broad. Costa not extended. R 4+5 ending clearly distal to apex of M 3+4; Cu 1 sinuate. Brachiolum with 1 seta, R with 2, R 1 with 1, R 4+5 with 2 setae, other veins bare.

Legs. Spur of front tibia 21 µm long, spurs of middle tibia both 14 µm long, of hind tibia 27 µm and 14 µm long. Width at apex of front tibia 19 µm, of middle tibia 21 µm, of hind tibia 27 µm. Comb of 11 setae, 14–23 µm m long. Lengths and proportions of legs as in Table 18.

Hypopygium ( Fig. 35 C ). Anal point 25 µm long; tergite IX with 7 setae; laterosternite IX with 2–3 setae. Phallapodeme 57 µm long; transverse sternapodeme 41 µm long, with weak or absent oral projections. Virga ( Fig. 35 D ) consisting of 11 µm long median spine and about 18 lateral spinules. Gonocoxite 126 µm long; superior volsella indicated; inferior volsella and accessory lobe well developed and reaching to 0.64 and 0.76 gonocoxite length, respectively. Gonostylus 57 µm long, upturned at apex; crista dorsalis indicated, megaseta 7 µm long. HR 2.10, HV 4.51.

Pupa (n = 3, except when otherwise stated)

Total length 2.02–2.78 mm. Exuviae with pale abdomen, cephalothorax tinged with yellow on margins.

Cephalothorax. Frontal apotome smooth or with only a few wrinkles, frontal warts absent or weak. Thorax entirely smooth or scutum or antepronotum with fine spinules. Longer precorneal, median antepronotal, single lateral antepronotal and fourth dorsocentral (Dc 4) all about 60–70 µm long. Shorter precorneals other Dc setae and frontal setae all about 25–45 µm long. Distance between Dc 1 and Dc 2 9–57µm; between Dc 2 and Dc 3 0–41µm; between Dc 3 and Dc 4 1–5 µm.

Abdomen ( Fig. 35 E, F ). Tergite I with coarse anterolateral shagreen, T II–VII with even shagreen covering most of segments. Caudal spinules slightly set off by weaker spinules in front. T IX with anterior shagreen. Sternites I–II bare; S III with few weak posteromedian spinules in male, absent in female; S IV with posterior spinules in male plus a few weak anteromedian spinules in both sexes; S VI–VIII with spinules covering most of segment, but very weak or absent medially; S IX bare. Tergal conjunctive II/III with 9–22 spinules, III/IV with 13–36, IV/V with 23–52, V/VI with 22–46, VI/VII with 26–60 spinules. Sternal conjunctives IV/V with 32–102 spinules, V/VI with 40–104, VI/VII with 30–74, VII/VIII with 23–48, VIII/IX with 9–16 (2) spinules in males, absent (1) in female. Anal segment with 1 basal seta about 45 µm long and apparently 2 apical setae each about 15 µm long. Male genital sac overreaching anal segment by 66–96 µm (2).

Female and larva

Unknown.

Distribution

In addition to the specimens from the type locality in Austria, there is a slide mounted exuviae in the Strenzke collection with label stating only Upjever ( Germany). The species also has been recorded from Hungary ( Saether & Spies 2004) .

Figures

FIGURE 35. Hydrosmittia brevicornis (Strenzke) comb. n. A—male wing; B—thorax; C—hypopygium, left dorsal aspect, right ventral aspect; D—virga; E—pupa, posterior tergites; F—pupa, posterior sternites.