Macropelopia nebulosa (Meigen)

Michailova, Paraskeva, Kownacki, Andrzej, Woźnicka, Olga, White, Keith, Dean, Andrew & Szarek-Gwiazda, Ewa, 2014, Macropelopia nebulosa group (Diptera, Chironomidae, Tanypodinae) — karyotype and morphology of larvae and pupae, Zootaxa 3852 (1), pp. 83-100 : 92-95

Macropelopia nebulosa (Meigen)

Larvae (n = 8). Fourth instar larvae 12 mm long. Head capsule rounded ( Figure 7 A), yellow, cephalic index about 0.9; body red, relative broad, with fringe of swim setae ( Figure 7 B), end of body ( Figure 7 C) with anal tubules situated at base of posterior parapod and shorter than parapods, procercus about 4– 5 x as long as wide, with 13 anal setae ( Figure 7 E), claws of parapod generally simple ( Figure 7 D), some with a very fine, poorly visible tooth on inner side ( Figure 7 D1), smallest claws simple, weakly curved.

Antenna. 320 µm long, 30% longer then mandible, antennal ratio 6.8, basal segment 6 x as long as width,

ring organ at beginning of distal 1/3 ( Figure 8 A1); segment II twice as long as segment III and IV together, last segment small, sharpened. Blade as long as segments II and III, accessory blade as long as segment II ( Figure 8 A2).

Mandible ± 220 µm long, moderately curved ( Fig 8 B), apical tooth black brown, small tooth-like points on ½ inner margin of mandible.

Maxillary palp ± 90 µm long, basal segment of palp 3.5x as long as vide, ring organ about 1/3 ( Figure 8 B). Mentum and M appendage. Dorsomentum with 8 teeth, distal part of M appendage and pseudoradula weakly granulose ( Figures 8 C, 8D).

Ligula with 5 teeth, central tooth lowermost, lateral highest, paraligula bifid (± 50 µm), about 1/2 as long as ligula, inner point very short ( Figure 8 E).

Pecten hypopharyngis ( Figure 8 F) with row of teeth (16–18) (poorly visible).

Pupa (n =10) large, 10 mm long, with characteristic thoracic horn ( Figure 9 A). Pupa with specific brown and yellow abdominal pigmentation patterns. Tergite I yellow without pigmented scar, tergites II–VII with brown M shape patterns and yellow place with tubercles on which is mounted spinous seta D1, tergite VIII brown without pattern ( Figure 9 B). Sternites with a broad, brown belt anteriory and narrow, yellow belt posteriorly ( Figure 9 C).

Thoracic horn relatively large, ± 1400 µm long, flattened ( Figure 10 A), covered with scales ( Figures 10 D, 10E), plastron plate half the length of the thoracic horn, plastron index = 0.5 ( Figure 10 A), with a reticular structure with holes ( Figures 10 B, 10C), the lower edge of plastron plate without visible light spots, respiratory atrium narrow.

Spines of abdominal shagreen apically sharpened, solitary ( Figure 11 D). Tergites II–V with transverse posterior band of larger teeth ( Figure 11 C). Conjunctives II/III, III/IV, IV/V, V/VI and VI/VII, VII/VIII with fine shagreen. Dorsal setae D1 ( Figure 11 E) arising from chitinised tubercle on tergites II–VI ( Figure 12 C), on tergite VII tubercle reduced ( Figure 12 A). Seta D3 on tergites III–V long, about 2x longer then seta D1, distally hooked ( Figures 12 D, 12E). Lateral setae on I–VI segment simple, short, mounted on a small tubercle. Segment VII with 6 long taeniate L setae, VIII with 5 ( Figures 11 A, 11B).

Anal lobe large, 2x long as segment VIII ( Figures 12 A, 12B), outer ¾ border slightly convex with 2 strong setae on basal part and dense fringe of hair-like setae on border, end of anal lobe sharpened and on outer and inner border with spinules.

Adult males. Description according to Fittkau (1962), Pinder (1978).

Ecology and distribution. Species common in Europe, East Palaearctic, Near East, North Africa, Oriental region (Fauna Europea 2013). Larvae live in fine sediment in springs, lakes, ponds, and rivers.

Figures

FIGURE 7. Macropelopia nebulosa (Meigen) larval morphology; A—head dorsal view and segment I with parapods (50 x); B—side view segment with fringe of swim-setae (75 x); C—end of larvae (50 x): PP—posterior parapods, TA—anal tubules, Pc—procercus, AS—anal seta; D—claws of posterior parapods; D 1 — claw of posterior parapod with fine point on inner margin, E—procercus with anal setae.

FIGURE 8. Macropelopia nebulosa (Meigen) larvae; A 1 — antenna and ring organ (RO); A 2 — top of antenna; BI—blade, ABI—accessory blade; B—mandible; C—mentum; MApp—M appendage, Dm—dorsomentum; D—dorsomentum; E—ligula Pl; F— pectin hypoparyngs PH.

FIGURE 9. Macropelopia nebulosa (Meigen) pupa; A—side view and thoracic horn: PP—plastron plate, RA—respiratory atrium; B—segments VI – IX dorsal; C—segments III – IX ventral.

FIGURE 10. Macropelopia nebulosa (Meigen) pupa (SEM); A—thoracic horn (magnification 75 x); B—structure of plastron plate (5000 x); C—structure of plastron plate (10000 x); D—externally scaled of thoracic horn (750 x); E—single scale (5000 x).

FIGURE 11. Macropelopia nebulosa (Meigen) pupa (SEM); A—segments V – VIII dorsal and anal lobe (35 x); B—lateral setation of dorsal segments VII – VIII (75 x); C—segment V dorsal (75 x); D—armament of tergites (750 x and 3500 x); E—spinous seta D 1 on sediment IV (500 x).

FIGURE 12. Macropelopia nebulosa (Meigen) pupa (SEM); A—side view (15 x); B—side view of anal segment (50 x); C—segments II – III; D—position of setae D 1 and D 3 (150 x); E—position of setae D 1 and D 3 (200 x).