Kloosia incurva, Mukherjee & Hazra, 2023

Mukherjee, Bindarika & Hazra, Niladri, 2023, Taxonomic studies on Harnischia complex from India (Diptera: Chironomidae), Zootaxa 5278 (2), pp. 239-263 : 243-245

Kloosia incurva sp.n.

GenBank Accession No. OP683429

urn:lsid:zoobank.org:act:0D8FAD19-2ADE-4456-963F-2E22C11D6057

Material examined. Holotype male, labelled ‘ Holotype Kloosia incurva sp. n., India, West Bengal, Purba Barddhaman [23.2393° N, 87.8512° E], 22.ix.2021, Coll. N. Hazra’ . Paratypes 3 males, labelled ‘ Paratype Kloosia incurva sp. n., India, West Bengal, Purba Barddhaman [23.2446° N, 87.8496° E], 30.iii.2022, Coll. B. Mukherjee’ .

Diagnostic characters. The adult male is distinguished by the following combination of characters: superior volsella with broad apex having 5–6 moderately long setae, elongated inferior volsella with short setae.

Etymology. The name ‘ incurva ’, originated from a Latin word ‘ incurvus ’, refers to the curved gonostylus at distal end.

Male (n=4). Total length 3–3.3, 3.165 mm. Wing length 1.55–1.7, 1.62 mm. Costal length 1.45–1.62, 1.53 mm. Antennal length 0.92–0.94, 0.93 mm.

Colouration. Thorax, leg and abdomen yellowish brown.

Head. Head width 440–500, 470 µm. Temporal setae 7–8 (IV 4, OV 3, Po 0–1). Clypeal setae 6. Frontal tubercles absent. Eyes bare with dorsomedial extension of 115–120, 117.5 µm. AR 1.4–1.5, 1.45; ultimate flagellomere 620– 630, 625 µm long. Palpomere lengths (I–V) (µm): 23: 25–27.5, 26.25: 66.5–70, 68.25: 94.5: 110.5–112, 111.25. CA 0.48–0.53, 0.505.

Thorax. Scutal tubercle absent. Ac 2, Dc 6, Pa 2, Scts 4, Su 1. Wing ( Fig. 2A ). VR 0.93–0.96, 0.945. R 1 without setae, R 4+5 with 3–4 setae. Brachiolum with 2 setae. Squama with 5 fringed setae. FCu distinctly distal to RM. Anal lobe moderately developed. Legs. Fore tibia with 2 setae. Mid legs with 2 tibial spurs; 16–18, 17 µm and 27.6 µm long with 16 lateral teeth. Hind leg with 2 tibial spurs; 18.4 µm and 23 µm long with 22 teeth. Lengths and proportions of leg segments shown in table II.

Hypopygium ( Figs. 2B–E ). Anal tergite band Y shaped. Anal point rounded apically, 57.5–60, 58.75 µm long and 11.5 µm wide at apex. Laterosternite IX with 2 setae on each side of anal point. Longitudinal and transverse sternapodeme 92–95, 93.5 µm and 27.5 µm long respectively. Superior volsella somewhat spatulate like at apex, 50–53, 52.5 µm long and 25.5µm wide at apex bearing 5–6 long setae. Elongated inferior volsella straight and distally widened bearing 5 small setae, 90–92 µm long and 30 µm wide at apex. Gonocoxite 132–138, 135 µm long. Gonostylus with partial cleft at apex, 149.5 –152, 150.75 µm long, fairly curved and swollen distally. HR 0.88–0.91, 0.895. HV 2.27–2.39, 2.33.

Distribution. India, West Bengal.

Remarks. Characters such as weakly appeared partial cleft on apex of gonostylus, non shortened inferior volsella with small setae and distally expanded superior volsella affirm positioning of the new species in the genus Kloosia Kruseman. Somewhat similar kind of superior volsella and anal point are present in both Kloosia dorsenna ( Saether, 1983) and the new species, but they differ in variable number of setae on superior volsella (5–6 setae on superior volsella of new species while it is 3 in number in K. dorsenna ), shape of gonostylus (roughly straight gonostylus present in K. dorsenna while distally curved in the new species.

A world key to the species of the genus Kloosia Kruseman (male)

1. Superior volsella not overreaching the anal point............................................................ 2

- Superior volsella overreaching the anal point............................................................... 4

2(1). Superior volsella with more than 2 setae; gonostylus distally thickened and strongly curved inwardly (Orient).................................................................................................... K. incurva sp. n.

- Superior volsella having 2 setae at apex; more or less straight gonostylus......................................... 3

3(2). Superior volsella somewhat rectangular shaped; inferior volsella longer than anal point (Holarctic)................................................................................................... K. dorsenna ( Saether, 1983)

- Superior volsella strongly curved at apex; inferior volsella not longer than anal point, more or less equal in length (Afrotropics)...................................................................... K. africana Reiss, 1988

4(1). Superior volsella slightly S shaped (Palaearctic, Oriental China).............................. K. koreana Reiss, 1988

- Superior volsella racquet like apically (Palaearctic)........................................ K. pusilla (Linné, 1767)

Figures

FIGURE 2. Adult male Kloosia incurva sp. n. A. Wing, B. Hypopygium (dorsal), C. Hypopygium (ventral), D. Hypopygium, scale 0.01 mm, E. Superior volsella, scale 0.01 mm.