Nanocladius (Plecopteracoluthus) shigaensis
- Dataset
- Nanocladius (Plecopteracoluthus) shigaensis sp. nov. (Chironomidae: Orthocladiinae) whose larvae are phoretic on nymphs of stoneflies (Plecoptera) from Japan
- Rank
- SPECIES
- Published in
- Inoue, Yasue, Komori, Chiharu, Kobayashi, Tadashi, Kondo, Natsuko, Ueno, Ryuhei, Takamura, Kenzi (2015): Nanocladius (Plecopteracoluthus) shigaensis sp. nov. (Chironomidae: Orthocladiinae) whose larvae are phoretic on nymphs of stoneflies (Plecoptera) from Japan. Zootaxa 3931 (4): 551-567, DOI: 10.11646/zootaxa.3931.4.5
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Insecta
- order
- Diptera
- family
- Chironomidae
- genus
- Nanocladius
- species
- Nanocladius shigaensis
etymology
Etymology. From the prefectural name (Shiga) of the type locality of the holotype. Adult male. Total length 2.1 – 3.4, 2.6 mm (16); wing length 1480 – 1900, 1706 Μm (13). Head brown, eyes darker, antennae and palpi light brown, thorax uniformly brown, vittae unclear, abdomen uniformly light brown; all fe (femora) brown, all ti (tibiae) with paler ring on apical half; fore ta (tarsi) light brown, mid and hind ta pale brown. Wing without pigmentation. Head (Fig. 1 A): Eye pear-shaped, without dorsomedial extension, densely hairy; ocelli lacking, genae not excavated; temporals generally reduced, IV (inner verticals), OV (outer verticals) 3 – 4, 3.6 (17). Coronal triangle filaments (called “ setae ” by Hayashi 1998) present (Fig. 1 B), apart from coronal triangle setae, as 2 pairs of long hyaline filaments branched at apical part, situated in and out of coronal triangle, inner filaments longer than outer: inner 60 ‒ 80, 70 Μm (15), outer 50 ‒ 70, 59 Μm (9). Tentorium 130 – 160, 146 Μm long (15), 17 – 30, 21 Μm wide (15). Clypeals 7 – 19, 11 (17). Antennal lengths 827 – 1030, 924 Μm (17), with 13 flagellomeres, AR 1.33 – 1.63, 1.40 (17), apical part slightly swollen, groove begins at 4 th flagellomere. Pm (palpomeres) without SCh (sensilla chaetica), lengths of each Pm, I 20 – 70, 37 Μm (14); II 60 – 90, 76 Μm (16); III 140 – 175, 151 Μm (16); IV 140 – 170, 153 Μm (16); V 220 – 300, 261 Μm (16). Thorax: Ap (antepronotal lobes) slightly gaping dorsomedially, with 1 – 7, 4.7 (13) lateroventral Aps (antepronotals); midscutum with longitudinal pale line area, but without Ac (acrostichals); numbers of Dc (dorsocentrals) 9 – 14, 11.3 (18) uniserial; Pa (prealars) 3 – 6, 4.7 (15); Scts (scutellars) 3 – 8, 5.6 (17). Wing (Fig. 1 C): Membrane bare, anal lobe developed, costa extended shortly, ending slightly beyond tip of M 3 + 4, VR (venarum ratio) 1.10 – 1.25, 1.16 (11), R 2 + 3 running near R 4 + 5 ending close to end of R 4 + 5, basal part of R with 0 – 2, 1.1 (8) setae, other veins without setae. Squamals 11 – 17, 13.5 (13). Legs: Ps (pseudospurs) absent, but spiniform setae present on tarsi of mid and hind legs; SCh absent; pulvilli well developed. Spur of fore tibia 43 – 60, 51.3 Μm (16); outer spur of middle tibia 14 – 20, 17.2 Μm (14), inner spur 20 – 27, 22.3 Μm (14); outer spur of hind tibia 15 – 23, 19.5 Μm (16), inner spur 42 – 60, 48.9 Μm (17), comb spines 14 – 17, 16.0 (15). Lengths and proportions of legs as in Table 2. Abdomen (Fig. 1 D): Tergal setae irregularly scattered, each seta arising from pale spot, number of setae on tergite I 34, II 55, III 53, IV 53, V 46, VI 35, VII 25, and VIII 22 (n = 1). Hypopygium (Fig. 1 E): Anal point completely absent, apical margin broad and rounded bearing several short setae; Sa (sternapodeme) concave, oral projection weakly developed, Vi (virga) absent; SVo (superior volsella) bare, broadly rounded; IVo (inferior volsella) well developed, triangular, setose caudally; Gs (gonostylus) parallel-sided, without distinct CD (crista dorsalis). fe ti ta 1 ta 2 ta 3 ta 4 N. (P.) PI 570 ‒ 710, 656, 655 ‒ 800, 755, 470 ‒ 580, 525, 395 ‒ 480, 438, 260 ‒ 330, 290, 160 ‒ 220, 196, shigaensis 41, n = 14 43, n = 16 28, n = 16 27, n = 15 17, n = 15 14, n = 15 N. (P.) 590 ‒ 630, 610, 560 ‒ 730, 683, 390 ‒ 530, 479, 310 ‒ 430, 392, 210 ‒ 295, 259, 140 ‒ 200, 182, asiaticus 16, n = 4 53, n = 7 44, n = 7 40, n = 7 40, n = 7 20, n = 7 PII 450 ‒ 650, 586, 520 ‒ 660, 594, 280 ‒ 360, 315, 150 ‒ 200, 183, 100 ‒ 125, 116, 50 ‒ 60, 57, 5, 59, n = 12 35, n = 13 22, n = 13 16, n = 13 10, n = 13 n = 13 420 ‒ 570, 526, 440 ‒ 580, 539, 220 ‒ 300, 283, 120 ‒ 185, 165, 90 ‒ 120, 106, 9, 40 ‒ 60, 51, 7, 50, n = 7 44, n = 8 27, n = 8 22, n = 8 n = 8 n = 8 PIII 550 ‒ 720, 628, 680 ‒ 890, 798, 370 ‒ 490, 426, 230 ‒ 310, 274, 165 ‒ 200, 191, 100 ‒ 125, 109, 43, n = 15 51, n = 16 30, n = 16 23, n = 16 11, n = 16 9, n = 16 460 ‒ 640, 580, 530 ‒ 750, 701, 300 ‒ 410, 382, 200 ‒ 280, 250, 130 ‒ 190, 176, 80 ‒ 105, 99, 8, 60, n = 7 72, n = 8 36, n = 8 23, n = 8 20, n = 8 n = 8 continued. ta 5 LR ti spur (PI), outer ti inner spur Number of ti spur (PII, III) comb spines N. (P.) PI 70 ‒ 100, 94, 8, n = 15 0.67 ‒ 0.73, 0.70, 43 ‒ 60, 51, 4, shigaensis 0.02, n = 15 n = 16 N. (P.) 70 ‒ 95, 90, 9, n = 7 0.68 ‒ 0.73, 0.70, 35 ‒ 65, 49, 8, n = 8 asiaticus 0.02, n = 6 PII 45 ‒ 60, 55, 5, n = 13 0.51 ‒ 0.55, 0.53, 14 ‒ 20, 17, 2, 20 ‒ 27, 22, 2, 0.01, n = 13 n = 14 n = 14 40 ‒ 60, 49, 6, n = 8 0.50 ‒ 0.54, 0.52, 15 ‒ 20, 19, 2, n = 8 18 ‒ 25, 22, 3, n = 8 0.01, n = 8 PIII 60 ‒ 95, 80, 9, n = 16 0.50 ‒ 0.56, 0.53, 15 ‒ 23, 20, 2, 42 ‒ 60, 49, 4, 14 ‒ 17, 16, 1, 0.02, n = 16 n = 16 n = 17 n = 15 50 ‒ 80, 70, 10, n = 8 0.53 ‒ 0.57, 0.55, 19 ‒ 20, 20, 0.4, 35 ‒ 50, 43, 5, n = 8 14 ‒ 17, 16, 1, n = 5 0.01, n = 8 n = 8 Adult female. Total length 2.0 – 3.2, 2.6 mm (6), Coloration: Head, antennae pale brown, eyes dark; thorax brown, vittae darker; wing bare, no markings; basal half and apical parts of all fe darker; all ta pale; abdomen brown. Head (Fig. 2 A): Genae not excavated. Labella about 2 times larger than those of the male. Eyes as in the male. In female adult coronal triangle absent, but 2 pairs of coronal triangle filaments present at frontal area (Fig. 2 B), inner filament 70 Μm long (1), outer filament 40 Μm long (1); IV absent, OV 2 – 4, 3.2 (6); tentorium 140 – 150, 145 Μm long (3), 10 – 15, 12 Μm wide (3); clypeals 11 – 18, 13.5 (4); antenna with 5 flagellomeres, lengths of fl-I 60 – 70, 64.6 Μm (5), fl-II 45 – 52, 49.2 Μm (5), fl-III 60 – 70, 65.4 Μm (5), fl-IV 60 – 80, 69.0 Μm (5), fl-V 102 – 120, 113 Μm (5); AR (5 th / 1 st – 4 th) 0.44 – 0.48, 0.46 (5). Thorax: Ac completely absent, Dc 13 – 20, 15.8 (5), uniserial; lateroventral Aps 6 – 8, 6.8 (4); Scts 8 – 11, 9.0 (5); Pa 5 – 7, 6.0 (4). Wing (Fig. 2 C): Length 1580 – 1760, 1685 Μm (5), VR 1.08 – 1.14, 1.11 (3), squamals 8 – 15, 12.3 (6). Abdomen: Tergal setae irregularly scattered. Legs: Lengths and proportions as in Table 3; pulvilli well developed. Genitalia (Fig. 2 D): SCa (seminal capsule) oblong, without microtrichia on surface, 90 – 100, 96.7 Μm long (3), 60 – 70, 63.3 Μm wide (3), with SDu (spermathecal duct) placed on mesal long side of SCa, with weak bend, without loop; No (notum) 170 – 180, 175 Μm long (2); Gc IX (gonocoxite IX) 14 – 22, 17.6 (5) setae, without caudomesal pointed projection (cf. Saether 1977 b: 89 couplet 26), Gp VIII (gonapophysis VIII) divided into three parts: VlL (ventrolateral lobe) rounded and setose, ApL (apodeme lobe) nearly straight, narrow, and bare, and DmL (dorsomesal lobe) surrounding vagina, setose; post-genital plate developed. fe ti ta 1 ta 2 ta 3 ta 4 N. (P.) PI 550 ‒ 650, 612, 690 ‒ 795, 731, 460 ‒ 510, 495, 350 ‒ 410, 387, 240 ‒ 290, 262 100 ‒ 195, 159, shigaensis 40, n = 5 39, n = 5 20, n = 5 23, n = 5 19, n = 5 36, n = 5 PII 530 ‒ 595, 575, 550 ‒ 600, 584, 280 ‒ 300, 295, 150 ‒ 170, 158, 95 ‒ 105, 100, 4, 40 ‒ 55, 49, 6, 31, n = 4 23, n = 4 10, n = 4 10, n = 4 n = 4 n = 4 PIII 540 ‒ 630, 590, 690 ‒ 800, 745, 370 ‒ 400, 390, 210 ‒ 240, 226, 160 ‒ 180, 169, 95 ‒ 100, 99, 3, 46, n = 3 47, n = 4 14, n = 4 14, n = 4 10, n = 4 n = 4 continued. ta 5 LR ti spur (PI), outer ti inner spur Number of ti spur (PII, III) comb spines N. (P.) PI 80 ‒ 95, 91, 7, n = 5 0.63 ‒ 0.71, 0.68, 30 ‒ 32, 32, 0.9, shigaensis 0.03, n = 5 n = 5 PII 50 ‒ 60, 54, 5, n = 4 0.50 ‒ 0.51, 0.51, 15 ‒ 18, 16, 1.5, 20 ‒ 21, 21, 0.5, 0.004, n = 4 n = 4 n = 4 PIII 70 ‒ 80, 75, 6, n = 4 0.50 ‒ 0.55, 0.52, 15 ‒ 18, 17, 2, n = 3 45 ‒ 55, 51, 5, n = 4 15 ‒ 18, 17, 2, n = 3 0.02, n = 4 Pupa (pupal exuviae). Total lengths 3.044 – 3.830, 3.476 mm (20). FA (frontal apotome) (Fig. 3 A) without additional warts, nearly smooth; FS (frontal setae) 22 – 77, 56.6 Μm (9); 2 medial and 1 lateral Aps present. TH (thoracic horn) (Fig. 3 B) 150 – 250, 198 Μm long (20), elongate, tapering toward apex covered with scale-like spinules in distal half; Pc 2 (Precorneals) much longer and stronger than 3 rd (Fig. 3 B); 4 Dc present, 2 nd and 3 rd closer to each other than to 1 st and 4 th, respectively; Pa absent. Abdominal tergites: PSA (pedes spurii A) and PSB (pedes spurii B) absent; T-II with row of posterior hooklets not on protuberance; T-IV – VI with median patch of spines, patch on VII vestigial (Figs 3 C, D). Posterior margins of T-II – VII with hooklets. Tergite setation: T-I with D (dorsal seta) 4 and L (lateral seta) 1; T-II D 4, L 2; T-III D 4, L 2; T-IV D 5, L 3; T-V D 5, L 3; T-VI D 5, L 3; T-VII D 4, L 2; T-VIII D 2, L 3 (n = 1), L 2 on T-VIII long; AL (anal lobe) with 38 – 40 taeniae in number and 3 pairs of macrosetae. Larva. Total length 3.0 – 6.0, 5.0 mm (27). Coloration of 4 th instar: Head capsule yellowish brown, eye spot in pale circle (Fig. 4 B), segments I – III (thorax) covered in large irregular dark markings, oral part of segment I changes to yellow before pupation, other segments pale yellow. Head capsule: lengths 380 – 510, 414 Μm (20); widths 290 – 400, 327 Μm (20); IC 0.73 – 0.89, 0.79 (20). Head capsule setation (Fig. 5, bottom): S 5 and S 8 very close compared with those of N. (P.) asiaticus (Fig. 5, top). Antenna (Fig. 6 A): with 5 consecutively smaller segments; AR 1.40 – 1.97, 1.61 (22); RO in basal 1 / 6 of segment I, occasionally antennal hair at base (1 / 22) [in N. (P.) asiaticu s more often (4 / 27)]. Bl (blade) shorter than segment II, LO (Lauterborn organ) distinct, as long as 3 rd segment. Labrum: SI spoon-shaped, apical margin finely serrate (Fig. 6 B); SII and SIII simple, ChL (chaetulae laterals) consist of 2 – 4 pairs of fish-shaped lamellae (Fig. 6 B). Mentum (Fig. 6 B): median tooth broad, with median shallow notch, 4 pairs of lateral teeth, VmP (ventromental plate) not elongate, beard absent, straight at caudal apex. SSm (seta submenti) 40 Μm long. MP (maxillary palp) (Fig. 6 C) consists of 2 parts: MP in narrow sense and lower bisensillum, each with some sensory organs. Pm (premandible) (Fig. 6 D): with faintly divided apical tooth, without brush. Mandible (Fig. 6 E): apical tooth longer than combined width of 3 inner teeth; SSd (seta subdentalis) long; Si (seta interna) with 7 – 8 branches, Parapods well developed, anterior parapod claws thin and long, serrated apical half, basal part of parapod covered with numerous short claws strongly serrated; claws of posterior parapod all simple. FIGURE 3. Pupa (PEX): A. Frontal apotome (scale bar 100 Μm); host Oyamia lugubris (Plecoptera). B. Thoracic horn, ring organ, and precorneals (Pc 1 – Pc 3) (200 Μm); host O. lugubris. C. Pupal abdominal tergite III – VI (1000 Μm); host O. lugubris. D. Pupal abdominal tergite VI ‒ anal lobe (400 Μm); host O. lugubris. Each body segment with short (c. 20 Μm long) setae, I and II 8, III 6, IV 4, V 6, VI – IX 8, X and XI 6; XII 0 or 2 in number. Procercus with 1 short (12 – 15 Μm) seta. Anal setae 4 – 6. Basoventral part of posterior parapod with 1 or 2 rather long (40 Μm) setae.
materials_examined
Type material. Holotype: Adult male, JAPAN: Aso River, Kutsuki-Aso, Takashima City, Shiga Prefecture (35 ° 37 ' 15 " N, 135 ° 89 ' 37 " E), collected on 01. XI. 2012, emerged on 10. XII. 2012, host Oyamia lugubris, Y. Inoue leg. (NSMT-I-Dip 7002). Paratypes: Adult male, sampling site, host, and collector as for the holotype, collected on 01. XI. 2012, emerged on 07. XII. 2012 (NSMT-I-Dip 7003); Adult male with PEX (pupal exuviae), Mugi River, Sembiki Bridge, Gifu Prefecture (35 ° 29 ' 27 " N, 136 ° 50 ' 36 " E), collected on 29. I. 2013, emerged on 10. IV. 2013, host Oyamia seminigra, Y. Inoue leg. (NSMT-I-Dip 7004); Adult male, Mugi River, Taniguchi-Waterfront Park, Mugigawa Town, Gifu Prefecture (35 ° 32 ' 31 " N, 136 ° 49 ' 26 " E), collected on 25. I. 2013, emerged on 20. III. 2013, host Oyamia cryptomeria, Y. Inoue leg. (NSMT-I-Dip 7005); Adult female, locality, host, and collector as for the holotype, collected on 01. XI. 2012 and emerged on 06. II. 2013 (NSMT-I-Dip 7006). Additional specimens from Aso River and Mugi River. Nanocladius (P.) shigaensis: Adult males 16, females 4, PEX 21, larvae 28; N. (P.) asiaticus: Adult males 8, females 9, PEX 8, larvae 31. All types including other specimens are deposited at the National Museum of Nature and Science, Tsukuba, Japan.