Simulium (Hearlea) canadense Hearle

Coscarón, S., Esquivel, D. R. Miranda, Moulton, J. K., Arias, C. L. Coscarón- & Bernal, S. Ibañez, 2004, Simulium (Hearlea) Vargas, Martínez Palacios, & Díaz Nájera (Diptera: Simuliidae): Taxonomic revision and cladistic analysis, Zootaxa 396, pp. 1-52 : 12-14

Simulium (Hearlea) canadense Hearle

Fig. 4C .

Simulium canadense Hearle 1932: 14 (as Simulium virgatum ssp.) 1935: 15, Figs. 1–4 .

Simulium (Hearlea) canadense Vargas & Díaz Nájera, 1957 b: 262–284 , Figs. 73–80; Díaz Nájera & Vulcano, 1962: 110, Figs. 6–10 ; Peterson, 1981:381, Figs. 47, 69, 90; Peterson & Kondratieff, 1994: 33–34, Figs. 193–210.

Female: Wing length, 3.4–3.8 mm. General coloration dark gray. Scutum blackish gray, clothed in silvery to greenish pilosity, with longitudinal submedial silvery vittae joining with 1+1 subtrapezoidal silvery anterior spots (changing to black with opposite light), lateral and posterior areas silvery gray pollinose; scutellum and metanotum brownish black; pleurae grayish pollinose. Abdomen grayish black, with lateral margin of tergite II and posterior 1/5 of tergites III–V silvery gray pollinose; tergites III–V blackish, subquadrate. Frons convergent below; fronto­ocular triangle about as broad as high. Sensory vesicle of palpus about 1/2 of basal article length, with abundant tubercles. Mandible with 12–27 teeth. Lacinia with 12–14 retrorse teeth. Basal portion of cibarium thick, smooth, medially concave, with 1+1 ovoid lateral prominences. Sc with 13 setae. Hind basitarsus 5.7–6.4 times longer than broad. Sternite VIII darkened medially, with about 14–20 hairs per side. Gonapophysis subtriangular, concave internally and blunt distally; cercus curved distally, anal lobe subrectangular, with relatively abundant hairs internally and transversal sulcus subbasally; genital fork with median stem capitate basally and with broad lateral arms bearing stout anteriorly directed apodemes; spermatheca ovoid, homogeneously sclerotized.

Male: Wing length, 3.1–3.3 mm. Scutum black, with anterior 1/3 light grayish pollinose, separated by black area and surrounding 1+1 subtriangular silvery spots. Hind basitarsus 3.8 times longer than broad. Dististylus about 1.8 times basistylus length, with small internally directed basal process; basistylus elevated laterally; ventral plate with median carina; endoparamere with strong hooks.

Pupa: Cocoon slipper shaped, closed anteriorly, coarsely woven, reinforced along anterior margin. Gill membranous with three pseudoannulated branches; medial branch largest, blunt apically, ventral branch directed anteriorly, roughly 1/2 width of medial branch and digitiform distally ( Fig. 4C ); dorsal branch 1/4 length of other branches, curved posteromedially. Frontoclypeus and thorax with numerous small granules. Cephalic and thoracic trichomes simple, stout. Abdominal tergite X with terminal spines markedly reduced.

Larva: Length (mature), 8.0–9.0 mm. Cephalic apotome without ornamentation, head ventrally darkened basomedially. Labral fan with 48–56 primary rays. Ratio of hypostoma length/length of hypostomal bridge = 1:1. Hypostoma with anterior margin straight, median tooth longer than corner teeth, 11–15 lateral setae per side, and 2–4 discal setae. Postgenal cleft dome shaped, with anteromedian incision. Mandible with internal teeth arranged in 2–3 rows of 5–8 teeth, two thickened marginal teeth, and one large lateral mandibular process. Ratio of antennal articles = 1:1.3–1.4:1.0–1.2 (proximal: medial: distal); medial article with 3–4 subdivisions. Lateral sclerite of prothoracic proleg with 24 teeth. Anal sclerite with hairs among struts. Posterior circlet with 102–158 rows of 18–20 hooks. Rectal papillae trilobed, with 5–8 lobules per lobe (15–24 total), dorsal lobule of each lobe greatly enlarged.

Material examined: (From USNM collection) Canada: British Columbia, Kamloops, 1 female (in slide), 2 females (paratypes), 29 May 1928 (Hearle); Kamloops, Cold Creek, 1 female pinned, 14 May 1930 (Hearle) (det as Simulium virgatum Coquillet , var. S. canadensis ); idem 1 male (paratype), 12 June 1930. U.S.A.: Washington, Tapenish, 1 male (in slide), several larvae and pupae, 18 June 1941, Knipling & Bishop; Waterville, several larvae and pupae, 15 June 1941, Knipling & Bishop; Montana, 3 females, Ravalli Co.; South Dakota, Spearfish, 1 male (in slide), 28 July 1924; California, Alpine Co. , Markleville, several pupae and larvae (1 larva in slide), 5 September 1938, Aitken & Cazier; Monterrey Co. , Greenfield, several larvae and pupae, 25 February 1955, Hitchcock; Calaveras Co. , Camp Wolfboro, Stanislaus R., 2 females (in slide), 18 females, 3 July 1940, Hardman ; Fresno Co. , 12 mi NE Academy, 1 female, February 1954, Bentenck ; same 6 females pinned, 11 April 1954; same 21 females pinned, 6 November 1954; San Diego Co. , Carrizo Creek , 1 male (in slide) 13 April 1948, Coleman ; San Diego ; 1 male pinned; Los Angeles Co. , Los Angeles , 10 females pinned; same 1 male (in slide) 1952, Mc Clay ; Tambark Flat , 1 female, 13 July 1952, Mc Clay ; Tule , Tulare river , 1 female, 25 April 1951, Bohart ; same 2 males, 20 June 1952, Mc Clay ; Hamilton Springs , 2 females, 19 May 1940, Aitken ; Nevada, Baker , 1 male pinned, 1 male (in slide), 29 September 1940, Tatcher ; Clark Co. , Lee Canyon , Mt. Charleston , several larvae, 20 May 1940, Bohart ; same 1 male, 24 May 1940, Reeves Cazeer & Ting; Deer Creek , several larvae, 25 May 1940, Cazier ; Arizona, Cochise Co. , S. W. Res. Sta., 1 male (in slide), 22 May 1965; 1 male (in slide), 28 May 1965. New México, Catron Co. , 5 mi E. Glenwood, 8 larvae (in slide), 24 June 1953, Wirth ; Santa Clara Co. , Hamilton Springs , 1 pupa (in slide), 19 May 1940, (Aitken). Plus material separated as S. canadense by Stone from California 25 females; Los Angeles Co. , 27 females; Fresno Co. , 1 male; San Diego Co. , 1 male; Nevada; 3 females Montana. Also was revised material from: New México, Catron , Grant , Lincoln , Mescalero Otero ; California, Del Norte , Humboldt , Los Angeles , Mangrosa , Monterrey , Riverside , Sacramento , Santa Clara , Tulare ; Utah, Salt Lake ; Texas, Kimble ; Washington, Helens .

Distribution: Canada: British Columbia; U.S.A.: Washington, Oregon, Montana, South Dakota, California, Colorado, Arizona, New México. México: Distrito Federal, Durango, México, Oaxaca, Puebla and Veracruz.

Bionomics: Larvae and pupae occur on vegetation in cool and clear flowing streams.

Discussion: This species is structurally similar to S. burchi and S. dalmati but the former species has a shoe­shaped cocoon and has a more strongly capitate, tubercled, medial gill branch; the latter species has both major gill branches multilobed apically.

Figures

FIGURE 1. Female. A–C. S. (H.) capricorne. A. front; B. fronto­ocular triangle; C. hind basitarsus. D. S. (H.) gorirossiae claw. E. S. (H.) larvispinosum claw. F–G. S. (H.) juarezi, scutum with varying lighting. H–I. S. (H.) microbranchium, scutum with varying lighting. Figures A and C, D and E, and F–I, with same respective scaling.

FIGURE 2. Female. A–E. S. (H.) capricorne, A. basal portion of cibarium, B. basal article of palpus and sensorial organ; C. VIII sternite and gonapophysis; D. paraproct and cercus; E. genital fork. F. S. (H.) delatorrei, basal portion of cibarium. G–I. S. (H.) larvispinosum, G. basal portion of cibarium, H. genital fork, I. spermatheca. (A, C, E, H, I) and (B, F) same scale respectively.

FIGURE 3. A–G Male. A. S. (H.) juarezi, scutum. B. S. (H.) capricorne hind basitarsus; C–E. S. (H.) delatorrei, C. basistylus and dististylus, D. ventral plate, E. endoparameres and median sclerite. F–G. S. (H.) larvispinosum F. basistylus and dististylus, G. ventral plate. H–I. pupa, frontoclypeus of S. (H.) capricorne and S. (H.) delatorrei respectively. (C, H) and (D, E) same scale respectively.

FIGURE 4. Pupa and respiratory organ. A, B. S. (H.) ayrozai, A. lateral view, B. dorsal view. C. S. (H.) canadense gill, lateral view; D, E. S. (H.) capricorne, D. lateral view, E. ventral view; F–I. S. (H.) ethelae, H. dorsal view; I. laterointernal view. J, K. S. (H.) microbranchium, J. lateral view, K. dorsal view; L–N. S. (H.) nigricorne N. dorsal view, M. laterointernal view. (A, D, F, H–N same scale).

FIGURE 6. Pupa and respiratory organ. A–E. S. (H.) larvispinosum; A. lateral view, B. dorsal view, C. lateroexternal view; D. laterointernal view; E. dorsolateral view, F–G. S. (H.) gorirossiae F. dorsal view. G. lateroventral view, H–I S. (H.) johnsoni, H. dorsal view, I. latero external view. J–K. S. (H.) menchacai, K. dorsal view. (A, J, K and C, B, D, I same scale respectively).

FIGURE 7. Abdominal chaetotaxy of pupa (S. (H.) capricorne, as example).

FIGURE 8. Larva A–C. S. (H.) capricorne A. head capsule, ventral view; B. hypostoma. C. mandible, distal portion. D–G. S. (H.) gorirossiae, D. cephalic apotome (basal portion) with cervical sclerites, E. antenna, F. mandible, ventral view; G. mandible, distal portion. H. S. (H.) larvispinosum, head capsule, ventral view. I–L. S. (H.) paracarolinae n. sp. I. head capsule, ventral view; J. hypostoma dental border; K. antenna, L. mandible, distal portion. (A–D), (B, J), (E, K), (H, I) same scale respectively.

FIGURE 9. A–J. Anal sclerite and accessory plates of larva. (d = dorsal branch of anal sclerite; v = ventral branch of anal sclerite; ds = dorsolateral conical accessory plate single; dd = dorsolateral conical accessory plates double; vl = ventrolateral accessory plate; df = dorsolateral flattened accessory plate). A. S. (H.) capricorne; B, C. S. (H.) paracarolinae B. dorsal view (cleared), C. posterodorsal view; D–F. S. (H.) gorirossiae D. posteroventral view, E. posterodorsal view, with rectal papillae (ap); F. ventrolateral papillae (vp) of segment VIII, sclerotized apical region; G. S. (H.) larvispinosum, lateral view, H. dorsal view, I. ventral view (cleared), J. S. (H.) temascalense. lateral view. (B, H, J) and (C, D, E) same scale respectively.

FIGURE 10. Distribution of Simulium (Hearlea).