Pseudosmittia angusta (Edwards)

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 : 255-258

Pseudosmittia angusta (Edwards)

( Figs. 95 B–F , 96 )

Spaniotoma (Smittia) angusta Edwards, 1929: 364 .

Smittia (Pseudosmittia) angusta (Edwards) ; Goetghebuer 1932:127, 1943: 104.

Pseudosmittia angusta (Edwards) ; Brundin 1956: 170; Strenzke 1960b: 427; Makarchenko & Makarchenko 2007: 305; Langton & Pinder 2007: 136, figs. 70 E, 186 D; Makarchenko & Makarchenko 2008: 216.

Material examined: ENGLAND: Hertfordshire., Knebworth , lectotype male, here designated, vi.1922, F. W. Edwards, BM 1922–350 ( BMNH) , paratypes 6 males, same data as holotype ; York, Skipwith , 1 male, 3.vii.1926, F. W. Edwards; 2 females without label (probably Skipwith), F. W. Edwards ( BMNH) . WALES: Carnaroon, Llyn Gwynant , 5males, 13.vii.1914, F. W. Edwards . SWITZERLAND: Locarno, Bolle di Magadino Piattone , cariceto 193.79 m, 14– 20.v.1998, 1 male, L. Pollini ( ZMBN) . CANADA: Ontario, Bells Corner , 2 larvae, 15.vii.1982, L. LeSage ( CNC) . USA: New Hampshire, Mount Washington, 2 larvae, 1.vii.1982, D. S. Chandler ( CNC) .

Diagnostic characters: The combination of antenna with apical seta, reduced wing anal lobe, Cu 1 straight, and distinct crista dorsalis will separate the male from other members of the angusta group. The female is characterized by having 6–10 inner verticals, costa with 7–11 non-marginal setae proximal to apex of R 4+5, tergite IX without posterior extension and LR 1 of 0.40–0.50. The pupa has no spinules on tergal conjunctive III/IV and on sternal conjunctives IV/V and VII/VIII of female, tergite IX without setae, and ventral spinules on genital sac. The larva can be separated from all members of the Pseudosmittia complex except P. simplex by lacking claws on the posterior parapods. From P. simplex it differs by having the antennal blade 2.0–2.4 times as long as the width of the basal antennal segment; anterior parapods each with about 20 longer claws, and seta submenti simple.

Male imago

All measurements and ratios with the range of variation of P. forcipata with the following exceptions and additions: Wing length/length of profemur 2.71–2.93, 2.77 (4); AR 0.54–0.72, 0.61 (7), terminal flagellomere ( Strenzke 1960b, fig. 21) 202–245, 221 µm (7) long; with strong 27–47, 39 µm (6) long apical seta; inner verticals 2–4, 3 (6); clypeus with 3–8, 6 (6) setae; third palpomere with 3–6, 4 (7) lanceolate sensilla clavata, fourth palpomere 55–69 µm (7) long; fifth 69–94, 87 µm (6) long; dorsocentrals 5–10, 7 (6); costal extension 21–37, 28 µm (4) long; Cu 1 straight or slightly curved ( Strenzke 1960b, fig. 22); LR 2 0.44–0.48, 0.46 (8); BV 2 3.85–4.33, 4.12 (8); SV 2 4.07–4.39, 4.24 (8); BR 2 2.6– 4.2, 3.2; LR 3 0.53–0.57, 0.55 (8); BR 3 3.5–5.0, 3.9 (8); gonocoxite ( Fig. 95 E ; Edwards 1929, fig. 7l, Strenzke 1960b, fig. 23) with superior and median volsellae, superior volsella 18–27, 24 µm (7) long, median volsella pointed, reaching posterior of inferior volsella 34–46, 40 µm long; inferior volsella 21–27, 25 µm (7) long, triangular; gonostylus with well developed apical crista dorsalis.

Female imago

All measurements and ratios within the range of variation of P. forcipata with the following exceptions and additions: Total length/wing length 1.53–1.69, 1.48 (5); first flagellomere 57–62 µm (3) long, fourth 37–59 µm (3) long, fifth with strong apical seta broken in specimens examined (but see Strenzke 1960b, fig. 24); tentorium 6–10, 9 µm (4) wide; stipes 16–32 µm (2) wide; fifth palpomere 59–73 µm (3) long; dorsocentrals 7–9, 8 (6) ( Strenzke 1960b, fig. 25); VR 1.28–1.44, 1.37 (5); costal extension 43–59, 48 µm (5) long; no anal lobe on wing ( Fig. 96 A ; Strenzke 1960b, fig. 22); Cu 1 straight; costa proximal of apex of R 4+5 with 7–11, 9 (6) non-marginal setae; BV 1 4.39–4.56 (3); LR 2 0.39– 0.45, 0.42 (4); BV 2 4.23–4.94, 4.56 (4); SV 2 4.32–4.82, 4.54 (4); LR 3 0.53–0.56, 0.55 (4); abdomen with 5–11, 8 (5) setae on each of tergites II–V, with 14–21, 17 (5) setae on sternite VIII; tergite IX ( Fig. 96 G ; Strenzke 1960b, fig. 26) deeply notched, with 12–20, 14 (5) setae; gonocoxites ( Fig. 96 F, G ) with rounded posterolateral corner; cercus 37–54, 45 µm (5) long; seminal capsule 62–78, 69 µm (5) long, no microtrichia observed; notum 69–105, 85 µm (5) long.

Pupa

No pupa was present in the material borrowed from NMS. The description by Strenzke (1960b), however is reasonably complete and is reiterated here.

Total length 1.7–2.0 mm. Nearly colorless.

Cephalothorax. Frontal apotome smooth in male, slightly rugulose in female, antepronotal area with a few wrinkles in female, smooth or at most with 1–2 wrinkles in male. Frontal seta about 20 µm long, median antepronotal about 15 µm long, lateral about 45 µm long, precorneals respectively 10, 40 and 50 µm long.

Abdomen. Tergite I bare in male, with a small group of about 12 isolated spinules in female or with very weak anterolateral spinules; T II–VIII with extensive shagreen, with bare preapical band on VIII, T IX of male with median spinules only, in female with additional lateral spinules situated on plate isolated from the tergite. Tergal conjunctives IV/V to VI/VII and sternal conjunctives VI to VI/VII in female, to VII/VIII in male each with 2 rows of numerous spinules. Anal segment without setae. Genital sac of male overreaches anal lobe by 2/5 of length of tergite IX, with strong ventral spinules.

Fourth instar larva (n = 2–4)

All measurements within the variation of P. forcipata with the following exceptions: AR 0.94–1.00 ( Fig. 96 H ); claws of posterior parapods absent.

Distribution

The species is known from the Finland, France, Germany, Italy, The Netherlands, Russia including Russian Far East ( Makarchenko & Makarchenko 2007, 2008), Sweden, Switzerland, and the UK ( Saether & Spies 2004), and from Canada and USA.

Figures

FIGURE 95. Pseudosmittia spp., male hypopygium. A—P. lamellata Andersen, Saether et Mendes. B–F. P. angusta (Edwards), male. B—cibarial pump, clypeus, torma and labial lonchus; C—tentorium and stipes; D—antepronotum; E—hypopygium, left dorsal aspect, right ventral aspect; F—virga.

FIGURE 96. Pseudosmittia angusta (Edwards), female, larva. A—wing; B—female antenna; C—dorsomesal lobe; D—ventrolateral lobe; E—apodeme lobe; F—genitalia, ventral view; G—genitalia, dorsal view; H—larval antenna; I—premandible; J—mandible; K—mentum; L–posterior end of larva.