Research Article |
Corresponding author: Chun-Cai Yan ( flyfish113@163.com ) Academic editor: Vladimir Blagoderov
© 2015 Chun-Cai Yan, Jiao Yan, Li Jiang, Qin Guo, Ting Liu, Xin-yu Ge, Xin-Hua Wang, Bao-ping Pan.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Yan C-C, Yan J, Jiang L, Guo Q, Liu T, Ge X-y, Wang X-H, Pan B-p (2015) Parachironomus Lenz from China and Japan (Diptera, Chironomidae). ZooKeys 494: 31-50. https://doi.org/10.3897/zookeys.494.6837
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Members of the genus Parachironomus Lenz known from China and Japan are revised, and a key to their male adults is given. Parachironomus poyangensis sp. n. is described in this life stage. Parachironomus frequens (Johannsen) and P. monochromus (van der Wulp) are recorded from China for the first time, thus are redescribed from Chinese specimens. Parachironomus kamaabeus Sasa & Tanaka and P. toneabeus Sasa & Tanaka are new junior synonyms of P. frequens. Three Chinese or Japanese species formerly placed in Parachironomus are transferred to other genera, resulting in the new combinations Cryptochironomus inafegeus (Sasa, Kitami & Suzuki), Demicryptochironomus (Irmakia) lobus (Yan, Sæther, Jin & Wang), and Microchironomus lacteipennis (Kieffer). Chironomus sauteri Kieffer, Parachironomus kisobilobalis Sasa & Kondo and P. kuramaexpandus Sasa are removed from Parachironomus; the last of these three denotes a valid species of uncertain generic placement, the first two are nomina dubia.
Chironomidae, Parachironomus, new species, new combinations, new synonyms, key
The name Parachironomus was proposed by
From 1985–2001, Sasa and various co-authors, and
Based on the known descriptions and material from China and Japan, the genus is reviewed, and one new species is described in the adult male stage. A key to adult males from China and Japan is provided.
The material examined was mounted on slides following the procedure outlined by
Type material studied is housed in the following institutions: Wang collection, Department of Biology, Life Science College, Nankai University, Tianjin, China (BDN); Sasa collection, National Science Museum, Tokyo, Japan (NSM).
1 | Tergite IX with shoulder-like caudal margin | 2 |
– | Tergite IX with triangle caudal margin | 4 |
2 | Gonostylus with distinct expansion basally; anal point parallel-sided | P. acutus (Goetghebuer) |
– | Gonostylus without distinct expansion basally or parallel-sided; anal point not parallel-sided | 3 |
3 | Anal point with constriction proximal of apical swelling; gonostylus with constriction in middle | P. frequens (Johannsen) |
– | Anal point pointed; gonostylus parallel-sided | P. swammerdami (Kruseman) |
4 | Gonostylus with distinct widening in distal 1/3; superior volsella slightly curved, swollen distally | P. monochromus (van der Wulp) |
– | Gonostylus widened basally or parallel-sided; superior volsella straightly, finger-like | 5 |
5 | Frontal tubercles absent; mid and hind tibiae each with 1 spur; gonostylus parallel-sided | P. poyangensis sp. n. |
– | Frontal tubercles present; mid and hind tibiae each with 2 spurs; gonostylus widened basally | P. gracilior (Kieffer) |
Chironomus frequens Johannsen, 1905: 230. –
Chironomus (Cryptochironomus) lhoneuxi Goetghebuer, 1921b: 168.
Cryptochironomus longiforceps Kieffer, 1921d: 66.
Harnischia (Harnischia) frequens (Johannsen). –
Parachironomus frequens (Johannsen). –
Parachironomus toneabeus Sasa & Tanaka, 1999: 38, syn. n.
Parachironomus kamaabeus Sasa & Tanaka, 2001: 45, syn. n.
CHINA: 1 male, Hebei Province, Zunhua City, Dongling, Longmenkou Reservoir, 7. vii. 2001, Y. Guo; 1 male, Yunnan Province, Kunming City, Yiliang County, 2. vi. 1996, X. Wang; 1 male, Xizang Autonomous Region, Nyalam County, Zhangmu Town, 2400 m, a. s. l., 16. viii. 1987, light trap, C. Deng.
JAPAN: Holotype of Parachironomus kamaabeus Sasa & Tanaka, 2001 (No. 391: 45), male, Gunma Prefecture, Tone River, Taisho Bridge, light trap, 1. vii. 1999. -Paratype of Parachironomus kamaabeus Sasa & Tanaka, 2001 (No. 391: 47), male, Gunma Prefecture, Tone River, Taisho Bridge, light trap, 3. vii. 1999.
The species is distinguished by the following combination of characters: mid and hind legs with dark brown rings, tergite IX with shoulder-like caudal margin; basal half of anal point with lateral setae, superior volsella finger-like.
(Chinese specimens). Male imago (n=3, unless otherwise stated). Total length 4.15–4.70, 4.46 mm. Wing length 1.98–2.54, 2.33 mm. Total length / wing length 1.78–2.10, 1.93. Wing length / length of profemur 2.20–2.47, 2.37.
Coloration. Thorax yellowish green to yellowish brown. Femora and tibiae of front legs yellowish green with distal 1/3 of tibiae and tarsi I dark brown, tarsi II with distal dark brown rings, tarsi III–V dark brown; femora and tibiae of mid and hind legs yellowish green, tarsi I, II of mid legs and tarsi I–III of hind legs pale with distal dark brown rings, tarsi III–V of mid legs and tarsi IV, V of hind legs completely dark brown (Fig.
Head. AR 2.66–2.86, 2.79. Terminal flagellomere 850–1030, 960 mm long. Frontal tubercles absent. Temporal setae 16–17, 17, including 3–4, 4 inner verticals, 7–9, 8 outer verticals and 5–6, 5 postorbitals. Clypeus with 19–26, 22 setae. Tentorium 100–150, 133 mm long, 40–50, 47 mm wide. Palpomere lengths (in mm): 37–55, 47; 55–68, 59; 145–220, 184; 160–213, 181; 178–338, 255. Length ratio 5th /3rd palpomere 0.95–1.71, 1.40.
Thorax. Antepronotals 3–5 (2), acrostichals 5–9 (2), dorsocentrals 10–12 (2), prealars 5–9 (2). Scutellum with 18–20 (2) setae.
Wing (Fig.
Legs. Front tibia with 3 subapical setae, 110 (1), 138–140 (2) and 150 (2) µm long; spurs of mid tibia 28–48, 36 and 33–50, 41 µm long, comb with 40–56, 47 teeth, 10–15, 12 µm long; spurs of hind tibia 33–55, 42 and 42–75, 56 µm long, comb with 56–68, 62 teeth, 10–15, 12 µm long. Tarsus 1 of mid leg with 22 sensilla chaetica, hind legs without sensilla chaetica. Lengths (in µm) and proportions of legs as in Table
Lengths (µm) and proportions of adult male legs in Parachironomus frequens (Johannsen), (n=3).
fe | ti | ta1 | ta2 | ta3 | ta4 | ta5 | LR | |
---|---|---|---|---|---|---|---|---|
p1 | 900–1030, 980 | 800–960, 893 | 1080–1250 (2) | 550–650 (2) | 420–500 (2) | 330–390 (2) | 150–200 (2) | 1.30–1.35 (2) |
p2 | 1030–1150, 1043 | 850–1060, 970 | 460–570, 523 | 280–350, 323 | 220–290, 260 | 150–190, 170 | 100–130, 116 | 0.54 |
p3 | 1060–1300, 1183 | 1100–1350, 1242 | 670–820, 757 | 440–550, 500 | 350–440, 400 | 220–270, 243 | 120–160, 140 | 0.61 |
Hypopygium (Figs
Holarctic (
Chironomus gracilior Kieffer, 1918: 49. –
Cryptochironomus arcuatus Goetghebuer, 1919: 66. –
Tendipes (Parachironomus) monotomus (Kieffer). –
Tendipes (Parachironomus) arcuatus (Goetghebuer). –
Tendipes (Cryptochironomus) arcuatus (Goetghebuer). – Goetghebuer (1937 in
Parachironomus gracilior (Kieffer). –
Parachironomus arcuatus (Goetghebuer). –
CHINA: 9 males, Tianjin City, Campus of Nankai University, 9 males, 12, 16. iv. 1985; 15. v. 1985; 20. iv. 1986, X. Wang; 1 male, Tianjin City, Shuanglin Farm, 20. vi. 1985, X. Wang; 1 male, Hebei Province, Qinhuangdao City, 1 male, vi. 1985, X. Wang; Hebei Province, Chicheng County, Yunzhou Reservoir, 21. vii. 2001, sweep net, Y. Guo and Y. Du. 1 male, Neimenggu Autonomous Region, Wuliangsuhai Lake, v. 1982, X. Wang; 1 male, Neimenggu Autonomous Region, Alashan League, Bayin, 30. vii. 1987, X. Wang; 1 male, Liaoning Province, Shenyang City, 27. viii. 1990, J. Wang; 1 male, Jiangxi Province, Poyanghu Lake, Nanjishan, 12. vi. 2004, Sweep net, C. Yan. 1 male, Yunnan Province, Kunming City, Dianchi Lake, 23. v. 1986, X. Wang; 1 male, Yunnan Province, Lijiang City, School of Agriculture Reservoir, 2400 m a.s.l., 28. v. 1996, X. Wang.
The species can be identified by the following combination of characters: anal point moderately narrow; frontal tubercles present; superior volsella bearing two apical setae, short cylindrical, often appearing more or less contracted, and with folds on inner margin; gonostylus with constriction at approximately mid-length.
The species is widely distributed in the Palaearctic and extends into the Oriental Region (
The synonymy between P. gracilior and P. arcuatus was accepted in the past already (e.g. by
Chironomus unicolor van der Wulp, 1859: 5 (primary homonym of C. unicolor Walker, 1848).
Chironomus monochromus van der Wulp, 1875: 129 (replacement name for C. unicolor van der Wulp).
Chironomus (Cryptochironomus) claviforceps Edwards, 1929: 389.
Tendipes (Parachironomus) monochromus (van der Wulp). –
Tendipes (Cryptochironomus gr. Parachironomus) monochromus (van der Wulp). – Goetghebuer (1937 in
Parachironomus monochromus (van der Wulp). –
CHINA: 8 males, Tianjin City, Campus of Nankai University, 8 males, 12, 16. iv. 1985; 20. iv. 1986, X. Wang; 1 male, Hebei Province, Weichang County, Jixielinchang, 15. vii. 2001, sweep net, Y. Guo.
The species is distinguished by the following combination of characters: anal tergite with distinct cluster of enlarged posterodorsal setae; anal point basal section intergrading with anal tergite, distal part strongly angled to ventral; superior volsella without apical or posterolateral projection; inferior volsella with lobe at least to median; gonostylus mostly slender, slightly curved, with distal widening to dorsal peaking around 2/3 of gonostylus length (excerpt from
(Chinese specimens). Male imago (n=9, unless otherwise stated). Total length 2.58–3.83, 3.38 mm. Wing length 1.30–1.98, 1.80 (8) mm. Total length/wing length 1.80–1.98, 1.88 (8). Wing length/length of profemur 2.28–2.57, 2.48 (8).
Coloration. Thorax yellowish green to dark brown. Front legs with femora yellowish green to dark brown, tibiae and tarsi dark brown except for tarsi I yellowish green in basal 4/5; mid and hind legs yellowish green to yellowish brown except for tarsi V dark brown. Abdomen yellowish green to dark brown.
Head. AR 1.86–2.27, 2.12. Terminal flagellomere 540–720, 673 µm long. Frontal tubercles absent (7) or present (2), cone-shaped, 15–22 µm high, 12–22 µm wide at base. Temporal setae 18–22, 20, including 5–7, 6 inner verticals, 7–8, 8 outer verticals, and 5–8, 6 postorbitals. Clypeus with 14–20, 17 (8) setae. Tentorium 100–133, 120 µm long, 18–43, 33 µm wide. Palpomere lengths (in µm): 30–50, 40; 35–58, 51; 103–133, 110; 130–180, 153 (8); 178–220, 201 (8). Length ratio 5th/3rd palpomere 1.21–1.73, 1.58 (8).
Thorax. Antepronotals 2–5, 3 (8), acrostichals 10–14, 12 (8), dorsocentrals 8–14, 11, prealars 4–6, 5 (8). Scutellum with 6–10, 8 (7) setae.
Wing (Fig.
Legs. Front tibia with 3 subapical setae, 90–130, 104 (7), 98–133, 118 (6) and 120–138, 126 (3) µm long; spurs of mid tibia 24–33, 28 µm and 28–35, 31 µm long, comb with 30–42, 35 teeth, 10–12, 11 µm long; spurs of hind tibia 26–33, 31 µm and 28–35, 33 µm long, comb with 45–52, 48 teeth, 10–13, 12 µm long. Tarsus 1 of mid leg with 4–7, 6 (8) sensilla chaetica, hind leg without sensilla chaetica. Lengths (in µm) and proportions of legs as in Table
Lengths (µm) and proportions of adult male legs in Parachironomus monochromus (van der Wulp) (n=9).
fe | ti | ta1 | ta2 | ta3 | ta4 | ta5 | LR | |
---|---|---|---|---|---|---|---|---|
p1 | 570–790, 727 | 420–620, 576 | 670–930, 863 (6) | 340–460, 432 (6) | 270–370, 342 (6) | 210–270, 247 (6) | 110–140, 133 (6) | 1.45–1.64, 1.55 (6) |
p2 | 550–780, 728 | 480–710, 640 | 260–360, 326 (8) | 140–310, 198 (8) | 100–160, 140 (8) | 70–110, 98 (8) | 60–90, 85 (8) | 0.44–0.54, 0.52 (8) |
p3 | 620–890, 818 | 610–950, 849 | 410–630, 557 (6) | 210–350, 312 (6) | 180–270, 247 (6) | 110–150, 143 (6) | 80–110, 104 (6) | 0.66–0.70, 0.67 (6) |
Hypopygium (Figs
Palaearctic (
Named after the type locality. The species epithet is adjectival for the purposes of nomenclature.
Holotype male (BDN No. 21987). CHINA: Jiangxi Province, Poyanghu Lake, Nanjishan Natural Conservation area, 12. vi. 2004, sweep net, C. Yan. Paratypes: 2 males, data same as holotype.
The new species is distinguished by the following combination of characters: body size small, thorax and abdomen yellowish green, wing cells without setae, mid and hind tibiae each with single spur, anal point nearly parallel-sided, superior volsella elongate digitiform, without distal swelling or projection, gonostylus nearly straight and of about even circumference throughout.
Male imago (n=3). Total length 2.25–2.32, 2.28 mm. Wing length 1.08–1.11, 1.10 mm. Total length / wing length 2.08–2.09, 2.09. Wing length / length of profemur 2.20–2.30, 2.25.
Coloration. Thorax yellowish green. Femora of front legs yellowish green with distal parts brown, tibiae and tarsomeres dark brown; mid and hind legs yellowish green with tarsomeres IV, V dark brown. Abdomen yellowish green.
Head. AR 1.76–1.84, 1.80. Terminal flagellomere 450–470, 462 mm long. Frontal tubercles absent. Temporal setae 11–13, 12, including 3 inner verticals, 3–4, 3 outer verticals and 5–6, 5 postorbitals. Clypeus with 15–18, 17 setae. Tentorium 90–95, 92 mm long, 25–26, 25 mm wide. Palpomere lengths (in mm): 25–27, 26; 30–32, 31; 83–85, 84; 98–104, 100; 145–156, 151. Length ratio 5th /3rd palpomere 1.75–1.78, 1.77.
Thorax. Antepronotals 3–4, 3; acrostichals 8–9, 9; dorsocentrals 10–12, 11; prealars 3. Scutellum with 5–6, 5 setae.
Wing (Fig.
Legs. Front tibia with 2 subapical setae, 108–110, 109 and 118–130, 126 µm long, mid and hind tibiae each with a single spur, spur of middle tibia 20–22, 21 µm long, comb with 28–30, 31 teeth, 10 µm long; spur of hind tibia 28–30, 29 µm long, comb with 42–46, 44 teeth, 10–12, 11 µm long. Tarsus 1 of mid leg with 6–7, 7 sensilla chaetica, hind leg without sensilla chaetica. Lengths (in µm) and proportions of legs as in Table
Lengths (µm) and proportions of adult male legs in Parachironomus poyangensis sp. n. (n=3).
fe | ti | ta1 | ta2 | ta3 | ta4 | ta5 | LR | |
---|---|---|---|---|---|---|---|---|
p1 | 470–500, 490 | 310–330, 320 | 540–560, 550 | 340-380, 360 | 230–250, 243 | 160–180, 166 | 90–100, 93 | 1.69–1.74, 1.71 |
p2 | 440–470, 456 | 350–380, 363 | 220–250, 233 | 120–140, 130 | 110–130, 120 | 70–80, 73 | 50–70, 60 | 0.63–0.66, 0.65 |
p3 | 480–530, 503 | 490–520, 506 | 340–370, 353 | 200–220, 210 | 170–200, 183 | 100–130, 113 | 70–80, 73 | 0.70–0.74, 0.72 |
Hypopygium (Figs
The species is known only from the type locality in Oriental China.
Cryptochironomus lacteipennis Kieffer, 1921a: 183.
Parachironomus lacteipennis (Kieffer) –
The species is recorded from Taiwan Province (Oriental China).
Chironomus (Cryptochironomus) sauteri Kieffer, 1921c: 583. –
Parachironomus sauteri (Kieffer). –
Cryptochironomus sauteri (Kieffer). –
The species is known from Taiwan Province (Oriental China).
Parachironomus kisobilobalis Sasa & Kondo, 1994: 129. –
JAPAN: Holotype of Parachironomus kisobilobalis Sasa & Kondo, 1994 (No. A 224: 49), male, Aichi Prefecture, Kiso River in dammed-up middle reach near Nagoya City, “emerged from a sample”, 26. ii. 1992.
We have examined the holotype, but it was lacking the thorax, head except for antenna, tarsi of front legs, and half of the hypopygium. As the preserved parts do not suffice for placement of the species, we treat P. kisobilobalis as a nomen dubium. In any case, the original description calling the superior volsella “rod-like, with one apical seta and 4 short setae along inner margin” and the inferior volsella “semicircular, with 4 short marginal setae” (
The species has been recorded only from the type in a Palaearctic part of Japan.
Among the many species previously reported in Parachironomus from Japan, only P. frequens, P. gracilior, P. monochromus, P. swammerdami, and possibly P. acutus (Original genus is Chironomus) are considered as valid records. Aside from the species treated in the present work, Parachironomus harunasecundus Sasa has been transferred to the genus Demicryptochironomus (
Based on examination of the holotype and paratype of Parachironomus lobus Yan, Sæther, Jin & Wang by M. Spies, P. lobus is related to Demicryptochironomus (Irmakia) latior, but conclusive placement would require knowledge of the immature stages. The end of the superior volsella looks less expanded than in D. latior. For the moment we propose the new combination Demicryptochironomus (Irmakia) lobus and try to find at least the pupa of this species for further comparison with D. (I.) latior and other congeners.
We are pleased to acknowledge the considerable assistance of Dr. A. Shinohara (Department of Zoology, National Science Museum, Tokyo, Japan), who kindly enabled us to examine Sasa type specimens. We thank M. Spies (Zoologische Staatssammlung München, Germany), Dr. T. Kobayashi (Institute for Environmental and Social Welfare Sciences, Japan), and Dr. Eugenyi Makarchenko and Dr. Oksana Zorina (Institute of Biology and Pedology, Far Eastern Branch of Russian Academy of Sciences, Vladivostok, Russia), for providing much input at various levels of this work.
We are indebted to the late Prof. O.A. Sæther (Museum of Zoology, University of Bergen, Norway) for kindly checking specimens and offering valuable comments during his visit to our laboratory in 2005. Financial support received from the National Natural Science Foundation of China (NSFC), grant No. 31101653, 31272284, Natural Science Foundation of Tianjin (14JCQNJC14600), Tianjin City High School Science & Technology Fund Planning Project (20090608), Undergraduate Training Programs for Innovation and Entrepreneurship (201410065046), and from the Tianjin Normal University Talent Introduction Foundation (5RL104) is gratefully acknowledged.