Simulium (Hearlea) contrerense Díaz Nájera & Vulcano

Simulium (Hearlea) contrerense Díaz Nájera & Vulcano, 1962: 94–99, Figs. 15–45.

(Description derived from Díaz Nájera & Vulcano, 1962).

Female: General coloration blackish. Scutum velvety blackish, with 1+1 silvery vittae not adjoining anteriorly with 1+1 submedian silvery triangular spots; lateral and posterior borders silvery pruinose. Abdomen brownish, with posterior margins of tergites yellowish. Basal portion of cibarium concave medially, without wrinkled margin and with thickened rim. Genitalia similar to those of S. capricorne .

Male: Wing length, 5 mm. General coloration blackish. Scutum velvety black, bordered with whitish pruinose and clothed in golden pile. Scutellum brown, with light brown posterior margin. Abdominal tergites black, with yellowish hairs. Sc haired. Genitalia as in S. capricorne . Ventral plate with prominent median carina.

Pupa: Length (basal), 7 mm; dorsal, 6 mm; gill, 3.5 mm. Cocoon shoe shaped, gradually elevated, closed basally on anterior 1/4, compactly woven, not reinforced along anterior margin. Thorax with 5 simple trichomes per side. Gill inflated, with 2 major branches; dorsal branch stout, subglobulose, tapered distally, sclerotized and wrinkled dorsally, ventral branch membranous and translucent ventrally, with subconical lateral prominence, and subannulations; ventrolateral branch small, thin, and curved medially.

Larva: Length, 12 mm. Head brownish, body yellowish gray, without ventral papillae. Labral fan with 42 primary rays. Hypostoma with 15–17 lateral setae per side and 4+4 discal setae. Mandible with 6–7 internal and 2 marginal teeth. Ratio of antennal articles = 1:2.2:1.9 (proximal: medial: distal). Postgenal cleft subtriangular. Posterior circlet with 185 rows of ca. 16 hooks. Rectal papillae trilobed, with 20–23 lobules per lobe (60–66 total), the dorsal lobe largest.

Distribution: México: México, 3000 m and D. F.

Discussion: The peculiar gill, with its inflated dorsal and ventral branches membraneous and translucent ventrally, distinguishes this species from all others. Simulium juarezi has a somewhat similar gill, but only its medial branch is markedly inflated.