Hydrosmittia oxoniana (Edwards)

Zhang, Ruilei, Liu, Wenbin, Ferrington, Leonard C. & Wang, Xinhua, 2016, Two new species of genus Hydrosmittia Ferrington & Saether (Diptera: Chironomidae) from China, Zootaxa 4121 (2), pp. 167-174 : 167-169

Hydrosmittia oxoniana (Edwards)

Camptocladius oxonianus Edwards, 1922: 204 .

Pseudosmittia oxoniana ( Edwards, 1922) ; Saether & Ferrington, 2003: 4; Saether 2006: 41; Langton & Pinder 2007: 137, figs. 71 A, 187 B.

Spaniotoma (Smittia) recta Edwards, 1929: 362 .

Pseudosmittia kurobeokasia Sasa &Okazawa, 1992a: 57 ; Yamamoto 2004: 89.

Pseudosmittia togarisea Sasa &Okazawa, 1992b: 160 .

Pseudosmittia hachijosecunda Sasa, 1994: 47 ; Yamamoto 2004: 87.

Pseudosmittia toyamaresea Sasa, 1996: 39 ; Yamamoto 2004: 89.

Pseudosmittia yakyopea Sasa &Suzuki, 2000a: 94 ; Yamamoto 2004: 90.

Pseudosmittia yakypequea Sasa &Suzuki, 2000a: 94 ; Yamamoto 2004: 90.

Parakiefferiella hidakagehea Sasa &Suzuki, 2000b: 188 ; Yamamoto 2004: 87.

Parakiefferiella hidakaheia Sasa &Suzuki, 2000b: 189 ; Yamamoto 2004: 87.

Prosmittia togarisea (Sasa &Okazawa) ; Yamamoto 2004: 78.

Pseudosmittia hidakagehea (Sasa &Suzuki) ; Yamamoto 2004: 87.

not C. oxonianus Edwards, 1937:146 (= H. ruttneri ).

Pseudosmittia recta (Edwards) ; sensu Wang, 2000: 639.

Hydrosmittia oxoniana (Edwards) ; Ferrington & Saether 2011: 120; Ashe & O’Connor, 2012: 324.

Material examined. 5 males, China, Yunnan Province, Dali City, Zhonghecun, 2300m, 22. V. 1996, light trap, X. Wang. 1 male, Ningxia Hui Autonomous Region, Mt. Helan, 26. VIII, 1 987, light trap, X. Wang.

Diagnostic character. The male imago differs from other members of the genus by having a long inner vertical, a more or less pronounced outer heel on the gonostylus and accessory lobe of inferior volsella which is not free at apex.

Male imago (n = 5)

Total length 1.60–1.92, 1.80 mm. Wing length 0.99–1.23, 1.12 mm. Total length/wing length 1.56–1.70, 1.61. Wing length/length of profemur 3.01–3.14, 3.07.

Coloration. Thorax brown, abdominal segments yellowish brown. Head, antenna and leg yellowish brown.

Head. AR 0.52–0.60, 0.56. Temporal setae 4–5, 5, including 1 inner vertical, 2–3, 3 outer verticals and 0–2,1 postorbitals. Clypeus with 5–10, 7 setae. Tentorium 98–125, 108 µm long, stipes 85–103, 91 µm long. Palpomere lengths (in µm): 28–38, 33; 30–42, 36; 65–74, 70; 68–75, 71; 88–102, 95. Length of 5th palpomere/ 3rd palpomere 1.06–1.46, 1.32. Third palpomere with 2 lanceolate sensilla clavata.

Thora x. Median antepronotal lobes well developed, antepronotum with 0–1, 1 lateral seta. Dorsocentrals 5–7, 6, acrostichals 1–2, 2, prealars 3. Scutellum with 3–4, 4 setae.

Wing. VR 1.29–137, 1.31. Anal lobe well developed, more or less projecting. Costal extension 13–23, 19 µm long. R4+5 ending slightly distal to apex of M3+4; Cu1 sinuate. Brachiolum with 1 seta, R with 1–2, 2 setae, other veins bare.

Legs. Spur of front tibia 25–30, 28 µm long, spurs of middle tibia 15–18, 16 µm long and 15–17, 16 µm long, of hind tibia 28–35, 31 µm and 13–18, 14 µm long. Width at apex of front tibia 23–28, 26 µm, of middle tibia 23– 25, 24 µm, of hind tibia 24–28, 25 µm. Comb with 10–13, 12 setae. Lengths and proportions of legs as in Table 1 .

Hypopygium. Anal point 10–27, 17 µm long, without microtrichia; tergite IX with 10–18, 14 setae; laterosternite IX with 3–5, 4 setae. Phallapodeme 38–45, 40 µm long; transverse sternapodeme 50–63, 59 µm long, with well developed oral projections. Virga consisting of weak median plate 5–7, 6 µm long. Gonocoxite 130–162, 147 µm long; inferior volsella usually well developed, reaching to 0.53–0.60, 0.55 gonocoxite length; accessory lobe not free at apex, reaching to 0.67–0.75, 0.70 gonocoxite length. Gonostylus 58–65, 62 µm long with more or less pronounced outer heel; megaseta 8–10, 9 µm long. HR 2.26–2.50, 2.37, HV 2.69–3.06, 2.90.

Distribution. Yunnan Province (Oriental China) and Ningxia Hui Autonomous Region (Palearctic China), China. It is widely distributed in the Holarctic region as in Ashe & O’Connor, 2012 and newly recorded in the Oriental Region in the present study.

Remarks. Edwards (1922) described Hydrosmittia oxoniana (as Pseudosmittia ) from Bear Island based only on female imagines. Later Edwards (1937) described the male from Swedish Lapland. However, the species described from Lapland is a synonym of H. ruttneri Strenzke & Thienemann (1941) , while H. oxoniana is the senior synonym of Pseudosmittia recta (Edwards) . Saether (2006) revised Japanese Pseudosmittia Edwards and placed 8 species erected by Sasa and co-workers as synonyms of Hydrosmittia oxoniana (as Pseudosmittia ). Wang (2000: 639) also mistakenly listed H. oxoniana Edwards as Pseudosmittia recta (Edwards) . Compared with descriptions of H. oxoniana by Ferrington & Saether (2011), the body size of the Chinese specimens are much smaller.

Tables

TABLE 1. Lengths (in µm) and proportions of legs of Hydrosmittia oxoniana (Edwards).

Fe	ti	ta1	ta2	ta3	ta4
P1 315–395, 364	405–500, 470	195–230, 216	120–140, 135	90–105, 97	50–65,59
P2 390–480, 446	395–480, 457	200–230, 219	110–125, 121	90–105, 95	45–60,53
P3 365–460, 420	410–510, 474	215–250, 232	125–145, 139	115–135, 126	50–65, 59
ta5	LR	BV	SV	BR
P1 50–60, 54	0.44–0.48, 0.46	2.95–3.07, 3.04	3.69–4.07, 3.86	2.17–3.00,2.53
P2 50–60, 54	0.46–0.51,0.48	3.34–3.60, 3.47	3.93–4.27,4.12	2.50–4.00, 3.14
P3 50–60, 54	0.45–0.52,0.49	2.91–3.03,2.98	3.60–4.20,3.85	3.00–3.83,3.45