Pseudosmittia christmasensis, 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 : 203-205

Pseudosmittia christmasensis sp. n.

( Fig. 77 )

Type material: Holotype male, KIRIBATI: Kiritinati (Christmas Island), Dolly’s Beach, 10.31° S, 105.33° W, 25.iv.1989, J. C. Cardale ( CSIRO) . – Paratypes: KIRIBATI: Kiritinati , Hughes Dale, 10.29° S, 105.33° E, 2 males, 25.iv.1989, J. C. Cardale; Nr. Greta Beach, 10.30° S, 105.41° E, 1 male, 26.iv.1989, J. C. Cardale ( CSIRO) .

Diagnostic characters: The male imago is separable from other members of the littoralis group by having nonbranched postcubitus, an almost straight gonostylus without crista dorsalis, and an HR of 1.96–2.09.

Etymology: From Christmas Island and the Latin suffix - ensis, meaning belonging to.

Male imago (n = 3–4, except when otherwise stated)

Total length 1.24–1.55, 1.38 mm. Wing length 0.70–0.84, 0.76 mm. Total length/wing length 1.70–1.92, 1.82. Wing length/length of profemur 2.89–3.04, 2.94. Coloration brown.

Head ( Fig. 77 B ). AR 0.78–1.05, 0.89. Terminal flagellomere 217–288, 239 µm long, no strong apical seta. Temporal setae 4–6, consisting of 2–3 inner verticals and 2–3 outer verticals, no postorbitals. Clypeus with 8–11 setae. Tentorium ( Fig. 77 B ) 91–94 µm long, 15–16 µm wide. Stipes 73–87 µm (2) long, 27 µm (1) wide. Palpomere lengths (in µm): 16–21, 18, 21–27, 24, 37–46, 41, 43–62, 54, 73–94. Third palpomere with 3–5 scalpellate sensilla clavata.

Thorax ( Fig. 77 C ). Antepronotal lobes reduced medially, with 1 lateral seta. Dorsocentrals 10–11, 10, acrostichals 2, prealars 3–4, 4. Scutellum with 6 setae.

Wing ( Fig. 77 A ). VR 1.76–1.82. Postcubitus unbranched. Anal lobe weak. Costal extension 5–14, 10 µm long. R 4+5 ending well proximal to apex of M 3+4; Cu 1 very slightly sinuate. Brachiolum with 1 seta, other veins bare.

Legs. Spur of front tibia 27–31, 30 µm long, spurs of middle tibiae both 27 µm (1) long, of hind tibia 27–39, 33 µm and 21–23, 22 µm long. Width at apex of front tibia 17–19, 18 µm, of middle tibia 18–21 µm, of hind tibia 23–34, 28 µm. Comb of 10–13, 11 setae, shortest seta 18–24, 21 µm long, longest seta 30–32, 31 µm long. Lengths and proportions of legs as in Table 47.

Hypopygium ( Fig. 77 E ). Anal point 18–23, 20 µm long, with 10–12 lateral setae; laterosternite IX with 2–3, 3 setae. Phallapodeme 41–48, 43 µm long; transverse sternapodeme 23–32, 28 µm long. Virga ( Fig. 77 D ) 16–23, 20 µm long. Gonocoxite 103–110, 107 µm long; inferior volsella triangular and reaching to 0.69–0.77, 0.75 gonocoxite length. Gonostylus 53–55, 54 µm long, attenuate; megaseta 7 µm long. HR 1.96–2.09, 2.02, HV 2.26– 2.92, 2.59.

Female, pupa and larva

Unknown.

Remarks

One of the specimens from Hughe Dale has a more blunt inferior volsella and a slightly higher AR than the three other specimens and could conceivably belong to another species. However judging on the variation found in related species the specimen is within the normal variation often seen from longer series of specimens.

Distribution

The species is only known from the type locality on Kiritinati.

Figures

FIGURE 77. Pseudosmittia christmasensis sp. n., male. A—wing; B—top of head, palp, tentorium and stipes; C—thorax; D— virga; E—hypopygium, left dorsal aspect, right ventral aspect.