Pseudosmittia digitrienta, 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 : 272

Pseudosmittia digitrienta sp. n.

( Fig. 103 C–H )

Type material: Holotype male, THAILAND: Mae Chaem District , Doi Inthanon, 22–29.viii.1983, H. Malicky ( ZSM) . – Paratypes 2 males, same data as holotype except 3–10.x.1989 and 28.viii.1990 ( ZSM) .

Diagnostic characters: The posterolateral corners of tergite IX, the relatively long costal extension and false vein, the lacking anal point, the median volsella together with the digitiform inferior volsella, and the long virga, easily separate the species from other members of the angusta group.

Etymology: From the Latin digitus, finger, and trientus, a third part, one third, referring to the digitiform inferior volsella.

Male imago (n = 3, except when otherwise stated)

Total length 1.66–1.83 mm. Wing length 1.09–1.16 mm. Total length/wing length 1.53–1.57. Wing length/length of profemur 3.00–3.01. Coloration brownish black.

Head ( Fig. 103 D ). AR 0.51–0.55. Terminal flagellomere 231–267 µm long. Temporal setae 3–5, consisting of 2–3 inner verticals, 1–2 outer verticals and 0–1 postorbitals. Clypeus with 4–6 setae. Cibarial pump and torma as in Fig. 103 E . Tentorium 87–98 µm (2) long, 11–16 µm (2) wide. Palpomere lengths (in µm): 21–23, 23–32, 57– 59, 59–69, 80–102. Third palpomere ( Fig.103 F ) with 4 sensilla clavata.

Thorax. Antepronotal lobes reduced medially, antepronotum with 1 lateral seta. Dorsocentrals 4, acrostichals 2, prealars 2. Scutellum with 4 setae.

Wing ( Fig. 103 C ). VR 1.29–1.32. Anal lobe weak. Costal extension 66–82 µm long, with false vein extending 137–191 µm from apex of R 4+5. R 4+5 ending slightly distal to apex of M 3+4; Cu 1 strongly sinuate. Brachiolum with 1 seta, other veins bare.

Legs. Spur of front tibia 30–34 µm long, spurs of middle tibia 15 µm (1) and 14 µm (1) long, of hind tibia 34– 40 µm (2) and 15–17 µm long. Width at apex of front and middle tibiae each 18–23 µm, of hind tibia 24–27 µm. Comb of 8–10 setae, shortest setae 18 µm long, longest setae 30 µm long. Tarsomeres lost. Lengths (in µm) of front to hind femora: 360–387, 432–468, 405–464; of front to hind tibiae: 454–513, 441–504, 450–495.

Hypopygium ( Fig. 103 G ). Tergite IX with posterolateral sharp corners, with 4–5 setae; laterosternite IX with 2 setae. Phallapodeme 57–71 µm long; transverse sternapodeme 50–69 µm long, no oral projections. Virga ( Fig. 103 H ) 71–73 µm long, dark in anterior half, nearly as long as gonostylus. Gonocoxite 123–128 µm long; superior volsella digitiform 25–29 µm long, and sharply pointed; median volsella 16–21 µm long; inferior volsella digitiform, 37–50 µm long. Gonostylus 80–85 µm long; megaseta 7–9 µm long. HR 1.51–1.56; HV 2.04–2.15.

Female, pupa and larva

Unknown.

Distribution

The species is only known from the type locality, the highest mountain in Thailand, 2577 m a. s. l.

Figures

FIGURE 103. Pseudosmittia spp., males. A, B. P. lamasi Andersen, Saether et Mendes. C–H. P. digitrienta sp. n. C—wing; D—head; E—cibarial pump and torma; F—third palpomere; G—hypopygium, left dorsal aspect, right ventral aspect; H— virga. (A, B from Andersen et al., 2010.)