Procladius (Holotanypus) rugulosus, Saether, Ole A., 2010

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 : 46-52

Procladius (Holotanypus) rugulosus sp. n.

( Figs 10 A–C; 12 D, J)

Procladius (Procladius) ? sp. n. Saether, 1977: 48.

Type material. Holotype, male, CANADA: Manitoba, Lake Winnipeg, Gull Harbor, 16. vi.1969, P.S.S. Chang ( CNC). Paratypes: Old Fishing Dock, light trap, 3 males, 14.vii.1971, E. Johnson, M. Roberts & S. Flam ( ZMBN, FWI); Old Fishing Dock, light trap, 2 males, 5.viii.1971, N. Hooper & E. Johnson ( ZMBN, FWI); Beaver Creek, emergence trap, 1 male, 29.vi.1971, E. Johnson, M. Roberts & S. Flam ( FWI, ZMBN). Other material: Beaver Creek, female reared from pupa, 8.vi.1971, M.P McLean et al. ( FWI).

Diagnostic characters. The male imago is characterized by the rugulose median dorsal surface of the gonocoxite. In other details it closely resembles P. culiciformis .

The presumed female has about 3 setae on anepisternum, about 4–5 sensilla chaetica on each ta1 of p2 and p3, and about 40 setae on segment X.

The presumed pupal exuviae has dark brownish tergites; plastron plate about 1.3 times as wide as apical constriction of horn chamber; thoracic horn about 0.53 mm long; and anal lobe with about 40 spines on outer margin, none on inner margin, and apical spines enlarged, but not set off from remaining spines.

Etymology. From Latin, rugulosus , full of wrinkles, referring to the rugulose median dorsal surface of the gonocoxite

Male imago (n = 5, except when otherwise stated)

Total length 3.21–3.82, 3.44 mm. Wing length 1.77–1.94, 1.81 mm. Total length/wing length 1.82–1.97, 1.90. Wing length/length of profemur 2.50–2.65, 2.59.

Head. AR 1.55–1.71, 1.64. Temporals 20–29, 23. Clypeus with 19–22, 21 setae. Cibarial pump, tentorium, and stipes as in Fig.10 A. Tentorium 184–194, 189 µm long. Stipes 150–185 µm long. Palpomere lengths 1–5 (µm): 33–47, 42; 55–74, 67; 80–99, 92; 105–132, 124; 179–215, 203 (4).

Thorax. Antepronotum with 11–18, 16 setae. Dorsocentrals 22–26, 24; acrostichals 35–40 (2): prealars 11–16, 14; prescutellars 6–9, 7; supraalar 1. Scutellum with 18–28, 23 setae.

Wing. VR 1.48–1.62, 1.53. Brachiolum with 2 setae; R with 13–18, 17 setae; R1 with 13–17, 15 setae; R4+5 with 19–33, 25 setae. Squama with 30–45, 37 setae. Extended part of costa 105–132, 112 µm long.

Legs (n = 3–5). Spur of front tibia 47–54, 51 µm long; spurs of middle tibia 41–51, 46 µm and 32–46, 38 µm long, of hind tibia 53–65, 60 µm and 34–43, 37 µm long. Width at apex of front tibia 47–54, 51 µm; of middle tibia 50–58, 54 µm; of hind tibia 61–72, 64 µm. Comb with 11–15, 12 setae; shortest seta 29–35, 32 µm long; longest 48–58, 54 µm. Sensilla chaetica absent. One tarsal pseudospur present on each ta1 and on ta2 of p2 and p3; pseudospurs 23–34, 29 µm long. Lengths and proportions of legs as in Table 1.

TABLE. 1. Procladius (Holotanypus) rugulosus sp. n., male. Lengths (in µm) and proportions of legs.

fe ti ta1 ta2 ta3 ta4

p1 672–755, 699 899–992, 926 598–694, 627 280–340, 303 213–258,230 147–177,158 p2 773–891, 807 815–925, 852 476–544, 507 230–270, 247 177–211,191 117–140,126 p3 672–756,702 941–1.057,993 619–680, 644 290–340, 318 210–250, 233 133–150,145

continued.

ta5 LR BV SV BR p1 95–113,106 0.66–0.70, 0.68 2.78–2.94,2.84 2.52–2.70,2.65 2.2–2.3, 2.2 p2 100–117,106 0.58–0.60, 0.59 3.20–3.40, 3.26 3.22–3.34, 3.31 2.2–2.8, 2.4 p3 109–115,112 0.63–0.67, 0.65 2.75–3.10, 2.90 2.58–2.69, 2.63 2.7–3.4, 3.1 Hypopygium ( Fig. 10 B). Tergites IX with 15–24, 20 setae. Transverse sternapodeme 167–201, 190 µm long. Phallapodeme 110–127, 117 µm long. Strut ratio 2.22–2.69, 2.55(4). Gonocoxite 203–223, 210 µm long, with 30– 38, 34 undulate wrinkles; gonostylus 89–108, 97 µm long; gonostylus ratio 2.81–3.36, 3.05. HR 2.06–2.27, 2.17; HV 3.49–3.73, 3.54.

Female imago (n = 1, tentatively associated)

Total length 4.49 mm. Wing length 2.81 mm. Total length/wing length 1.60. Wing length/length of profemur 2.20.

Head. AR 0.44. 12 flagellomeres, lengths of last 4 flagellomeres (µm): 29, 30, 31, 140. Temporals 75. Clypeus with 37 setae. Tentorium 216 µm long. Stipes 243 µm long. Palpomere lengths 1–5 (µm): 60, 100, 137, 200, 296.

Thorax. Antepronotum with 21 setae. Dorsocentrals 51, prealars 9, acrostichals 54, prescutellars 10, supraalar 1, anepisternum II with 3 setae. Scutellum with 31 setae.

Wing. VR 1.36. Brachiolum with 6 setae, R with 86 setae, R1 with 114 setae, R2+3 with 38 setae, R2 with 16 setae, R3 with 32 setae, R4+5 with 135 setae. Squama with 69 setae.

Legs. Spur of front tibia 87 µm long, spurs of middle tibia 77 µm and 63 µm, of hind tibia 93 µm and 60 µm long. Width at apex of front tibia 67 µm, of middle tibia 63 µm, of hind tibia 88 µm. Comb with 12 setae, 40–83 µm long. sensilla chaetica 4–5 at base of ta t of p2 and p3. Lengths and proportions of legs as in Table 2.

fe ti ta1 ta2 ta3 ta4 ta5 LR BV SV BR p1 1277 1412 1025 462 350 224 176 0.73 3.06 2.62 2.1 p2 1059 1395 857 408 299 187 173 0.61 3.10 2.86 -

p3 1143 1547 1109 537 381 220 206 0.72 2.83 2.43 2.4 Genitalia ( Fig.10 C). Cercus 87 µm long. Seminal capsule140 µm long, sclerotized in oral 83 µm, 113 µm wide. Notum 303 µm long. Segment X with about 40 setae.

Pupa (n = 1, tentatively associated)

Length 6.52 mm. Coloration of exuviae dark brownish with blackish brown anterior and posterior lines on tergites and sternites and paler lateral margins.

Cephalothorax. Thoracic horn ( Fig. 12 D) 534 µm long, 165 µm wide, 3.24 times as long as wide. Plastron plate 121 µm wide, 0.73 times as wide as thoracic horn, 1.26 times as wide as the 96 µm wide apical constriction of horn chamber.

Abdomen. Anal lobe ( Fig. 12 J) similar to P. denticulatus with 38 spines on outer margin, median 2–3 spines enlarged.

Remarks. The female reared from pupa is not definitely associated with the male. However, the chaetotaxy of the female shows that it cannot belong to any of the other species known from the lake and it is reared from the same locality as one of the male paratypes. The species appear to be closely related to P. culiciformis .

Distribution and ecology. The species has been found only in the shallow parts of the Narrows of Lake Winnipeg. However, if the larvae are inseparable from one of the other more common species the distribution could be wider.

Figures

FIGURE 10. Procladius spp., male. A – C. Procladius (H.) rugulosus sp. n; A—cibarial pump, tentorium and stipes; Bhypopygium; C—female genitalia. D— Procladius (H.) paragretis Roback, female genitalia.

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.