Procladius (Holotanypus) sublettei Roback

Saether, Ole A., 2010, Procladius Skuse from Lake Winnipeg, Manitoba, Canada, with keys to some females and immature stages of the genus (Diptera: Chironomidae), Zootaxa 2726, pp. 34-58 : 53-54

Procladius (Holotanypus) sublettei Roback

( Figs 6 C–G; 12 F, L; 13 E, G, J, M; 14 H)

Procladius (Procladius) sublettei Roback, 1971: 191 ; Roback 1980: 47; Saether 1977: 48. Procladius culiciformis auct. nec Linnaeus.

Material examined. CANADA: Manitoba, Lake Winnipeg, light traps: Victoria Beach, 4 males, 9. & 25.vii. 1969; Pine Dock, 22 males, 10.vii., 31.vii. & 2.ix. 1969; 0.5 km off George Island, 1 male, 12.vii. 1969; 10 km off (Sturgeonskin point) Long Point, 7 males, 14.vii. 1969; 3 km off McCreary Island, 12 males, 15.vii. 1969; Gull Harbor, 2 males, 16.vii. 1969; Grand Rapids Government Wharf, 6 males, 28.vii. 1969; 5 km off Selkirk (Horse) Island, 1 male, 29.vii. 1969; McBeth Harbor, 1 male, 7.ix. 1969; Gimli Government Wharf, 5 males, 9.ix. 1969; Beaver Point, 2 males, 30.vi. & 6.viii. 1971; 20 Mile Creek, 14 males, 26.viii. & 1.ix. 1971; Old Fishing Dock, 8 males, 29.vi., 18.viii. & 8.ix. 1971; Calder's Dock, 1 male, 31.viii. 1971; Hecla Island, 15 males, 25.viii. 1971; emergence traps: Beaver Creek, 23 males, 3.vi.–28.vii.1971; rearings: north of outer buoy Red River, 1 male, 4.vi. 1969; eastsoutheast of outer buoy Red River, 1 male, 1 female, 9.vii.1969; north of outer buoy Red River, 2 males, 9.vii. 1969; 13 km southwest of Bigstone Point, 1 male, 11.vii. 1969; Saskatchewan River Buoy, 1 male, 14.vii. 1969; 10 km east-southeast of Pearson Reef, 1 male, 26.vii. 1969; Pigeon Bay, 1 male, 27.vii. 1969; east of Selkirk Island, 1 male, 4.ix. 1969; 1 km west of Elk Island, 1 male, 4.x.1969; South Basin, 379 larvae, female reared from larva, 4.vi–31.x.1969; Narrows, 105 larvae, 4.vi–31.x.1969; North Basin, 226 larvae, 2 pupae, 4.vi–31.x.1969.

The male gonostylus ( Fig. 6 G) appear to be closest to the Pt. Pelee, Ontario, population figured by Roback (1971 fig. 376, 379) with some specimens falling in P. sublettei var. grandis . As indicated by Roback (1971: 193) the typical form and the variety may only represent different generations.

The female have no setae on anepisternum II, about 16–18 setae on segment X, and about 3–10 sensilla chaetica on ta1 of p2 and p3.

Pupa (n = 6)

Cephalothorax. Thoracic horn ( Fig. 12 F) 380–491, 433 µm long; 112–170, 143 µm wide, atrial wall of thoracic horn with reticulate pattern. Plastron plate diameter 90–144, 114 µm; apical constriction of horn chamber 46– 81, 63 µm wide length/width of horn 2.67–3.39, 3.10; width of plastron plate /width of horn 0.66–1.03, 0.78; width of plastron plate/width of constriction 1.38–2.57, 1.87.

Abdomen. Spinules on T IV small, grouped ( Fig. 12 N). Anal lobe ( Fig. 12 L) with 36–40, 38 spines on outer margin, densely grouped posterolaterally, usually one at apex of inner margin, and apical spines relatively small and set off from remaining spines.

Fourth instar larva (n = 10, except when otherwise stated)

Head capsule length 720–908, 812 µm (672).

Head. Antenna as in Fig. 13 E, G. Lengths of antennal segments (in µm): 165–205, 190; 18–24, 21; 6–8, 7; 2– 3, 3; 1–2, 2. AR 5.50–6.85, 6.14)[4.44–5.50 in Roback (1980)]. Basal antennal segment 32–42, 38 µm wide; 4.46– 5.56, 4.97 times as long as wide; ring organ 0.65–0.79, 0.72 from base; blade 24–33, 29 µm; accessory blade 20– 26, 22 µm long. Apical style of second segment 6–8, 7 µm long. Apex of labrum as in Fig. 13 J. Mandible 174– 202, 191 µm long [ 148–185 µm in Roback (1980)]. Maxilla about as in P. denticulatus ( Fig. 14 C). Maxillary palp ( Fig.14 H) 46–58, 48 µm long; 17–21, 19 µm wide; 2.35–2.71, 2.51 times as long as wide. Length of basal antennal segment/length of palp 3.37–4.46, 3.96. Hypopharyngeal pecten ( Fig. 13 M) with 13–14, 13 teeth.

Abdomen. Claws of posterior parapods all relatively long and slender.

Distribution. The species, when including the varieties, is known from all over USA and Canada ( Roback 1971: 192–195; Oliver et al. 1990: 15; Spies 1999; Epler 2003, 2010; Caldwell 2009). It is, however, more common in southern parts. The distribution in Lake Winnipeg is shown in Fig. 1 , the emergence pattern in Fig. 11 .

Figures

FIGURE 1. Larval distribution of the five most common species of Procladius Skuse in the benthos of Lake Winnipeg.

FIGURE 6. Procladius spp., male. A, B. Procladius (H.) denticulatus Sublette; A – cibarial pump, tentorium and stipes; B – hypopygium. C – G. Procladius (H.) sublettei Roback; C—cibarial pump, tentorium and stipes; E—thorax; F, G—hypopygium.

FIGURE 11. Procladius (Holotanypus) sublettei Roback. Numbers of adults caught in light traps and emergence traps in 1969 and 1971, and numbers of immatures in benthic samples from June to November 1969 and in March 1970. (LT = light traps, ET = emergence traps, vertical lines = 1 – 25 specimens, 2 = second instar larvae, 3 = third instar larvae, 4 = fourth instar larvae, P = pupae.)

FIGURE 12. Procladius spp., pupae; thoracic horn (A – F), anal lobe (G – L), spinule pattern of tergite IV (M, N). A, G – Procladius (P.) bellus; B, H— Procladius (H.) freemani Sublette; C, I— Procladius (H.) culiciformis (L.); D, J— Procladius (H.) rugulosus sp. n.; E, K, M— Procladius (H.) denticulatus Sublette, F, L, N— Procladius (H.) sublettei Roback.

FIGURE 13. Procladius spp., larvae, antennal apex (A – E), antenna (F – G), labrum (H – J), and ligula, paraligula and hypopharyngeal pecten. A, F, H, K— Procladius (P.) bellus (Loew); B, I, L— Procladius (H.) freemani Sublette; C— Procladius (H.) culiciformis (L.); D— Procladius (H.) denticulatus Sublette; E, G, J, M— Procladius (H.) sublettei Roback.

FIGURE 14. Procladius spp., larvae; maxillae ventral view (A – B), dorsal view (C); maxillary palp (D – H), claws of posterior parapods (I – L). A, D, I, J— Procladius (P.) bellus (Loew); B, F, K— Procladius (H.) culiciformis; C, G, L— Procladius (H.) denticulatus Sublette; E— Procladius (H.) freemani Sublette; H— Procladius (H.) sublettei Roback.