Helopelopia pilicaudata (Walley)

Saether, Ole A., 2011, Notes on some tanypods from Lake Winnipeg, Manitoba, Canada (Diptera: Chironomidae), Zootaxa 3069, pp. 26-42 : 34

cf. Helopelopia pilicaudata (Walley)

( Fig. 5 A–D)

Material examined. CANADA: Manitoba, Lake Winnipeg: South Basin, 1 larva, 3.–12. x.1969; Narrows, 1 larva, 9.–17. vii. 1969; North Basin, 5 larvae 9.–17. vii., 1969.

These larvae may belong to Helopelopia according to Epler (2001, couplet 36).

Fourth instar larva (n = 1–3)

Total length 6.12–11.33 mm. Head capsule length 0.99–1.08 mm.

Head. Apex of antenna as in Fig. 5 A. Lengths of antennal segments (in µm): 415–440, 73–81, 7–9, 3–4, 2. AR 4.44–4.66. Basal antennal segment 30–35 µm wide, ring organ 0.67–0.70 from base, blade 76–86 µm. Style at apex of second segment 12 µm long. Apex of labrum as in Fig. 5 B. Mandible 210–244 µm long. Basal segment of maxillary palp ( Fig. 5 C) 72–90 µm long, 14–22 µm wide, 3.91–5.14 times as long as wide. Ligula ( Fig. 5 D) 114–128 µm long. Paraglossa ( Fig. 5 D) 46–48 µm long.

Abdomen. Body with long hairs 0.8–1.0 times as long as width of segments. Procercus 156–170 µm long, 50– 53 µm wide, 2.94–3.20 times as long as wide. Anal setae 920 µm, supraanal seta 620 µm, supraanal seta/anal setae 0.67. Anal tubules 290–340 µm long. Posterior parapods 689–810 µm long, with 3–4 very slightly darker claws.

Third instar larva (n = 3)

Total length 4.61–6.11 mm. Head capsule length 0.64 mm.

Head. Lengths of antennal segments (in µm): 230–238, 46–48, 7–8, 2–3, 1. AR 3.90–4.30. Mandible 134–138 µm long.

Abdomen. Procercus 90–106 µm long, 34–38 µm wide, 2.37–3.06 times as long as wide.

Remarks. The larvae of Helopelopia Roback are larger than larvae of Conchapelopia Fittkau ( Roback 1981: 100, Epler 2001 couplet 36). The present specimens are larger than mentioned by Roback (1981) for H. cornuticadata (Walley) and since H. pilicaudata is present in Lake Winnipeg likely belong to that species or species complex.

Figures

FIGURE 5. Tanypodinae immatures. A – D, cf. Helopelopia pilicaudata (Walley), larva, antennal apex (A), labral apex (B), maxillary palp (C), ligula, paraligula and hypopharyngeal pecten (D); E – H, cf. Conchapelopia currani (Walley), larva, antennal apex (E), labral apex (F), maxillary palp (G), ligula, paraligula and hypopharyngeal pecten (H); I – L, Telopelopia okoboji (Walley), larva, antennal apex (I), labral apex (J), ligula, paraligula and hypopharyngeal pecten (K), thoracic horn and comb of pupa (L); M — Larsia canadensis Bilyj, larva, antennal apex.