Bryophaenocladius sclerus

Wang, Xinhua, Liu, Zheng & Epler, John H., 2004, New species of Bryophaenocladius Thienemann from the Nearctic Region (Diptera: Chironomidae: Orthocladiinae), Zootaxa 581, pp. 1-10 : 5-7

Bryophaenocladius sclerus sp. n

( Figs. 7–9 )

Type material. Holotype male, USA: North Carolina: Swain Co., GRSM, Left Fork, Deep Creek, 3500 ft, 8. IV. 1993, G. Salansky, P93­43. Paratypes: 11 males, USA. Tennessee: Sevier Co., GRSM, Silers Creek, Site #1 3500 ft, 7. iv. 1993, leg. C. R. Parker, P93­44.

Etymology. From the Greek skleros, hard, referring to the strongly sclerotized inferior volsella.

Male imago (n = 11, except when otherwise stated).

Total length 2.92–3.54, 3.28 mm. Wing length 1.74–1.76, 1.75 mm. Total length / wing length 1.66–2.01, 1.87. Wing length / length of profemur 2.35–2.44, 2.40. Coloration dark brown.

Head. Terminal flagellomere 592 long, without strong subapical seta. AR 1.95 (n=1). Temporal setae 8–9, 8; including 3–4, 4 inner verticals, 2 outer verticals and 2–4, 3 postorbitals. Clypeus with 6–8, 7 setae. Tentorium 170–180, 176 long; stipes 108–128, 118 long. Palpomere lengths: 32–40, 35; 56–70, 64; 132–144, 139; 114–120, 117; 146–148, 147. 3rd palpomere without sensilla clavata.

Thorax. Antepronotum with 4–6, 5 setae. Dorsocentrals 15–18, 16, acrostichals 8–13, 11, very decumbent, prealars 6–9, 8. Scutellum with 12–14, 13 setae. Humeral pits small, rounded.

Wing ( Fig. 7 ). Anal lobe protruding. Moderately coarse punctation easily visible at 100x magnification. VR 1.17–1.19, 1.18. R2+3 ends 1/2 distance between R1 and R4+5. Costal extension 20–26, 23 long. Brachiolum with 3–4, 4 setae; R with 10–14, 13 setae; R4+5 with 3–4, 4 setae, remaining veins bare. Cu1 slightly curved. Squama with 16–17, 17 setae.

Legs. Spur of front tibia 92–100, 95 long, spurs of middle 62­68, 65 and 34–40, 37 long, of hind tibia 94–106, 99 and 36–42, 38. Hind tibial comb with 7–9, 8 setae. Pseudospurs present on ta1 of middle and hind legs. All tibial spurs with weak developed denticles. Lengths and proportions of leg segments:

Hypopygium ( Figs. 8, 9 ). Anal point hyaline with semicircular apex; 12–24, 18 long, 60–82, 69 wide at base. Anal point length/width 0.20–0.34, 0.26. Tergite IX broad, with 16–24, 19 long setae; laterosternite IX with 9–12, 11 setae. Phallapodeme 122–142, 133 long; transverse sternapodeme 128–156, 137 wide, weakly arcuate with developed oral projection. Virga 36–56, 44 long, composed of cluster of 5–7, 6 spines. Gonocoxite 256– 280, 268 long. Gonostylus strongly curved, 134–136, 135 long, with 3 stout setae situated on inner side. Inferior volsella naked, well sclerotized and low dome­shaped. Crista dorsalis low and present at apex of gonostylus. Megaseta 20–22, 21 long. HR 1.91–2.06, 2.01, HV 2.15–2.64, 2.41.

Distribution. The species is known from Great Smoky Mountains National Park in North Carolina and Tennessee.

Remarks. The prominent sclerotized, bare inferior volsella, combined with the short costal extension, short and broad anal point, and strongly curved gonostylus easily separate B. sclerus sp. n. from other known species of the genus. Female and immature stages unknown.

Figures

FIGURES 7 – 9. Bryophaenocladius sclerus sp. n. Holotype, male imago: 7. Wing; 8. Hypopygium, dorsal aspect; 9. Hypopygium, ventral aspect.