Ablabesmyia (Ablabesmyia) monilis (Linnaeus)

Niitsuma, Hiromi, 2013, Revision of the Japanese Ablabesmyia (Diptera: Chironomidae: Tanypodinae), with descriptions of three new species, Zootaxa 3664 (4), pp. 479-504 : 481-485

Ablabesmyia (Ablabesmyia) monilis (Linnaeus)

( Figs 1–15 )

Tipula monilis Linnaeus, 1758: 587 .

Ablabesmyia monilis: Fittkau 1962: 437 ; Sasa & Kawai 1987: 55. Ablabesmyia (Ablabesmyia) monilis: Roback 1971: 375, 1985: 185 . Ablabesmyia yufucomplexa Sasa & Suzuki, 1991: 99 .

Ablabesmyia tomoteria Sasa, 1993: 58 .

Ablabesmyia moniliformis: Niitsuma 2005:1053 , fig. 16.6–9. [nec Fittkau, 1962]

Material examined. Holotype of Ablabesmyia yufucomplexa : male (NSMT-I-Dip4833), labelled, “No. 222:50”, JAPAN: Oita, Yufu, 11.x.1990. Holotype of Ablabesmyia tomoteria : male (NSMT-I-Dip4906), labelled, “No. 244: 51”, JAPAN: Toyama, Tomosaka, 21.vi.1992. Non-types. JAPAN: Fukushima, Iwaki, Hisanohama, Ôbisa River, 1 female with pupal and larval exuviae (SUM-IC-T0397), 1.ix.1989 (adult emerged 16.ix.1989); Shizuoka, Surugaku, Nagasawa River, 1 male with pupal and larval exuviae (SUM-IC-T0398), 8.x.1997 (adult emerged 21.x.1997); Shizuoka, Suruga-ku, Abe River, 2 males (SUM-IC-T0399, T0400), 6.vi.2004 (adults emerged 19.vi.2004); Shizuoka, Iwata, Tsurugaike, 2 males with 1 pupal exuviae (SUM-IC-T0401, T0402), and 4 females with 4 pupal and 1 larval exuviae (SUM-IC-T0403–T0406), 8.v.1999 (adults emerged 17–21.v.1999); Nagasaki, Iki Island, Ashibe, 1 male (SUM-IC-T0407) and 2 females (SUM-IC-T0408, T0409), 24.vii.2006.

Description. Male (n = 8). Body length 3.1–4.5, 3.9 (6) mm.

Colouration. Thorax yellow with dark brown scutal vittae, anepisternum II, preepisternum and postnotum. Abdominal tergites I–V, IX pale yellow, and tergites VI–VIII more or less darkened anteriorly. Wing ( Fig. 1 ) with dark spots on humeral cross-vein, RM, FCu, and on costal vein and surrounding areas at apices of R1, R2, R3 and R4+5; membrane with many dark spots; dark macula in middle of cell r4+5 above spot in middle of cell m1+2. Leg segments white with dark bands; subbasal and median bands on foretibia located 0.80–0.82 and 0.40–0.43, respectively, from apex of tibia.

Head. Temporals 29–45, 36 (5), multiserial except uniserial postorbitals. AR 1.8–2.1. Clypeus trapezoid, with 33–50, 41 (6) setae. Lengths of palpomeres 1–5 (μm): 58–70, 66 (3); 125–145, 135 (3); 175–195, 185 (3); 135–145 (2); 300–333, 316 (3). Pm4 0.73–0.74 times as long as Pm3; Pm5 2.3 times as long as Pm4.

Thorax. Aps 9–15, 12 (5); Ac 58–72, 66 (4), biserial between median scutal vittae, diverging posteriorly; Dc 20–42, 31 (4), uniserial, but anteriorly biserial; H 9–19, 13 (4); Pa 19–34, 26 (5); Su 1 (4); Scts 44–53, 48 (6).

Wing. Length 2.1–3.1, 2.7 (6) mm. Squama with 42–75, 56 (6) setae. VR 0.85–0.87.

Legs. Spur on foretibia 55–68, 63 (6) μm long with 8–10, 9 (4) lateral teeth. Spurs on mid tibia 65–78, 74 (6) and 30–45, 37 (6) μm long, with 7–10, 8 (3) and 6–7, 6 (4) lateral teeth, respectively; inner spur 1.7–2.2 times as long as outer spur. Spurs on hind tibia 63–78, 72 (6) and 30–43, 35 (6) μm long, with 7–8 (2) and 4–5 (2) lateral teeth, respectively; inner spur 1.8–2.3 times as long as outer spur; hind tibial comb consisting of 5–7, 6 (6) bristles. All legs with subapical pseudospurs on ta1–3; claws pointed or weakly bifid apically, each with 2 (6) long and 2–4, 3 (6) short basoventral spines. Lengths and proportions of leg segments as in Table 1 .

Hypopygium ( Fig. 2 ). Tergite IX with 2–4, 2 (6) lateral setae. Gonocoxite 158–220, 197 (6) μm long; dorsal lobe 40–43, 41 (6) μm long, with apical fringe of outwardly curving setae; blade sinuate, tapering toward rounded apex, 63–78, 72 (6) μm long, with pointed basal projection; lateral lobe not evident; lateral filaments well developed ( Fig. 3 ). Gonostylus 145–205, 188 (6) μm long, 0.92–0.98 times as long as gonocoxite, with megaseta expanded apically.

Female (n = 7). Body length 1.9–3.1, 2.5 (6) mm.

Colouration. Similar to male. Subbasal and median bands on foretibia located 0.76–0.83 and 0.35–0.44, respectively, from apex of tibia. Seminal capsule brown on oral half.

Head. Temporals 30–43, 36. Antenna with terminal flagellomere distinctly longer than preceding 3 flagellomeres together; AR 0.30–0.34. Clypeus with 35–67, 51 (6) setae. Lengths of palpomeres 1–5 (μm): 55–65, 59 (5); 103–125, 113 (5); 135–180, 156 (5); 108–140, 119 (5); 255–268, 259 (5). Pm4 0.71–0.78 times as long as Pm3; Pm5 1.9–2.2 times as long as Pm4.

Thorax. Aps 7–17, 13; Ac 70–97, 82 (6); Dc 27–45, 35; H 16–33, 24; Pa 29–45, 37; Su 1–2, 1; Scts 51–73, 64. Wing. Length 1.9–2.8, 2.3 mm. Squama with 50–70, 62 setae. VR 0.84–0.90.

Legs. Spur on foretibia 50–65, 56 μm long with 8–10, 9 (6) lateral teeth. Spurs on mid tibia 58–73, 65 and 25– 43, 34 μm long, with 8–9, 9 (4) and 4–7, 6 (4) lateral teeth, respectively; inner spur 1.6–2.4 times as long as outer spur. Spurs on hind tibia 60–70, 66 and 20–38, 31 μm long, with 7 (2) and 5 (2) lateral teeth, respectively; inner spur 1.8–3.3 times as long as outer spur; hind tibial comb consisting of 5–6, 5 bristles. All legs with subapical pseudospurs on ta1–3; hind leg with 9–21, 15 sensilla chaetica on basal 0.49–0.66 of ta1. Lengths and proportions of leg segments as in Table 1 .

Genitalia ( Fig. 4 ). Gonocoxapodeme VIII well developed. Gonapophysis VIII tongue-shaped. Gonapophysis IX well developed; notum 103–163, 129 μm long, almost twice as long as ramus. Labium without microtrichia. Seminal capsule oval, 68 (1) μm long and 63 (1) μm wide. Segment X reduced, with 0–3, 1 fine seta on each side. Postgenital plate rounded apically.

Pupa (n = 7). Body length 4.8–5.7, 5.2 mm.

Colouration. Exuviae pale brown, with distinct pigmentation pattern; wing sheath infuscated along margin and veins, without any dark spots; abdominal tergites II–VII each with dark transverse band along posterior margin, and pair of dark medial vertical bands or anteromedial patches ( Fig. 5 a, b).

Cephalothorax. Thoracic horn ( Fig. 6 ) bulbous, 424–566, 504 μm long and 1.6–1.8 times as long as broadest width; apex of aeropyle tube club-shaped ( Fig. 7 ). Thoracic comb composed of 8–14, 10 teeth with rounded apices.

Abdomen ( Fig. 8 ). Tergal shagreen ( Fig. 9 ) consisting of slightly arched, transverse rows of 2–3 or more spinules. LS1-seta on A.VII located 0.40–0.50 from anterior margin, and on A.VIII located 0.34–0.37. Anal lobe 505–566, 540 μm long, 2.3–2.7 times as long as wide, with anterior and posterior anal macrosetae located 0.46– 0.54 and 0.56–0.63, respectively, from anterior margin; outer margin of lobe spinulate. Male genital sac 0.71–0.72 as long as anal lobe.

Fourth instar larva (n = 3).

Colouration. Head yellow with dark postoccipital margin; body entirely yellow when live. Head ( Fig. 10 ). Length 960 (1) μm; cephalic index 0.58. Ventral cephalic seta S10 anterolateral to sensory pore; lines S9-VP and S10-VP making right or somewhat obtuse angle. Antenna ( Fig. 11 ) 0.56 (1) times as long as head capsule; lengths of segments 1–4 (μm): 408–445, 424; 68–71 (2); 5 (2); 4 (2). AR 4.8–5.6. First antennal segment 14.0–14.8 times as long as basal width, with ring organ located 0.56–0.60 from base; blade 70 (1) μm long, reaching apex of 2nd segment; accessory blade 73 (1) μm long. Second antennal segment 13.5–14.3 times as long as basal width; style 8 (1) μm long, reaching middle of 4th segment; peg sensillum 2 (1) μm long. Mandible ( Fig. 12 ) 150–158, 154 μm long, 0.29–0.32 times as long as antenna; basal tooth large with tip directed apically; accessory tooth distinct. Basal segment of maxillary palp ( Fig. 13 ) subdivided into 1 short (p3) and 2 long parts (p1, 2), 93–103 (2) μm in total length, and 5.3–5.9 times as long as basal width; p2 3.0–3.5 times as long as p3, and slightly shorter than p1. Ligula ( Fig. 14 ) 110–113 (2) μm long, 1.9–2.0 times as long as toothed width, with basal granulose area occupying 0.23–0.24 of total length; toothed margin concave; middle tooth 1.5–1.8 times as long as wide. Paraligula bifid, 48–50 (2) μm long, with fork located 0.47–0.50 from base; outer spine 2.5–3.3 times as long as inner spine. Pecten hypopharyngis with row of 19–20 (2) teeth.

Body. Procercus 3.6 times as long as basal width, with 7 apical setae; both lateral setae located 0.34–0.36 and 0.62–0.67, respectively, from base. Posterior parapod with 16 claws including 1 brown and 2 blackish brown claws; smallest claw sharply bent with large basal expansion; large claws finely spinulate along inner and outer margins ( Fig. 15 ).

Remarks. I could not find any significant difference between the present species and A. (A.) monilis (Linnaeus) reported from Europe (Roback 1959: 128, Fittkau 1962: 437, Pinder 1978: 30 as adults; Fittkau 1962: 437, Langton 1984: 46 as pupae; and Laville 1971: 188, Rieradevall and Brooks 2001: 92, Vallenduuk & Pillot 2007: 74 as larvae) and North America (Roback 1959: 128, 1971: 375 as adults, Roback 1985: 185 as pupae and larvae; and Epler 2001: 4.22 as larvae).

Tokunaga (1937) described Pentaneura monilis based on many adult specimens collected from Kyoto, Wakayama, Tottori and Tokushima, Japan. It appears that his P. monilis series may, in fact, consist of two or possibly three species including A. (A.) monilis , A. (A.) prorasha and A. (A.) jogancornua , judging from his drawing of the wing with three dark spots along the costal margin (Tokunaga 1937, fig. 66). The critical form of the aedeagal complex was not included in his figure 80 of the hypopygium. Twenty-six specimens used in his description still exist in the Kyushu University Museum (Tadauchi and Yamamoto, pers. comm.), although their conditions have considerably deteriorated over the long-term storage in alcohol. Fittkau (1962) erected Ablabesmyia moniliformis as a new species for Tokunaga’s P. monilis . However he had not provided a diagnostic description, nor made reference to one, nor designated a holotype, but yet the proposed name satisfies the provisions of Article 13.1.2 of the Code and thus is considered as a nomen dubium.

Figures

FIGURES 1 – 4. Ablabesmyia (Ablabesmyia) monilis (Linnaeus), male (1 – 3) and female (4). 1, Wing; 2, hypopygium, dorsal view; 3, aedeagal complex, dorsal view; 4, genitalia, ventral view.

FIGURES 5 – 15. Ablabesmyia (Ablabesmyia) monilis (Linnaeus), pupa (5 – 9) and larva (10 – 15). 5 a, b, Abdominal segment IV, dorsal view, showing variation of pigmentation pattern; 6, thoracic horn; 7, apex of thoracic horn with apical nipple; 8, abdominal segments VII – IX, dorsal view, all dorsal and left lateral setae omitted; 9, shagreen on posteromedial part of abdominal tergite IV; 10, head with chaetotaxy, dorsal view (D) and ventral view (V); 11, antenna; 12, mandible; 13, maxillary palp with apical stylets; 14, ligula, paraligula and pecten hypopharyngis, right pecten hypopharyngis omitted; 15, medium- and small-sized claws of posterior parapod.

Tables

TABLE 1. Lengths (μm) and proportions of legs of Ablabesmyia (Ablabesmyia) monilis (Linnaeus), male (n = 5) and female (n = 7).

fe Male	ti	ta1	ta2	ta3	ta4	ta5	LR	BR
P1 828–1010 909	970–1162 1067	788–1010 909	455–646 572	343–465 412	222–303 271	131–172 156	0.81–0.87	3.4–5.5
P2 929–1172 1052	899–1091 1004	768–899 826	444–505 479	333–384 360	212–253 234	131–162 147	0.78–0.85	5.4–6.6
P3 859–1040 945	1141–1384 1260	1101–1283 1174	606–697 640	434–505 465	273–333 303	141–182 164	0.90–0.97	6.1–6.8
Female
P1 687–929 805	758–1071 915	626–869 752	354–525 437	253–384 322	192–263 227	121–162 143	0.81–0.84
P2 788–1141 975	778–1131 972	636–869 765	343–495 427	263–364 313	182–242 211	111–152 136	0.75–0.82
P3 707–1010 863	919–1374 1150	828–1182 1024	444–667 566	333–495 417	212–313 260	121–172 147	0.84–0.93