Bryophaenocladius polychaetus, Wang, Xinhua, Liu, Zheng & Epler, John H., 2004

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 : 4-5

Bryophaenocladius polychaetus sp. n.

( Figs. 4–6 )

Type material. Holotype male, USA: North Carolina: Swain Co., Poplar Hollow Branch; Malaise trap, 16 Aug–10 Oct 2001; leg. RC Harrington, DR Jones.

Etymology. From the Greek polys, many, and chaite, hair, referring to the setose inferior volsella.

Male imago (n=1)Total length 2.33 mm. Wing length 1.27 mm. Total length/wing length 1.84. Wing length / length of profemur 2.16. Coloration yellowish brown.

Head. Antenna lost. Temporal setae 9, including 3 inner verticals, 6 outer verticals. Clypeus with 7 setae. Tentorium 133 long; palpomere lengths: 27, 42, 95, 90, 101, the 3rd palpomere with a cluster of 4 sensilla clavata.

Thorax. Antepronotum with 3 setae. Dorsocentrals 11, acrostichals 6, bi­serial and very decumbent, prealars 6. Scutellum with 3 setae.

Wing ( Fig. 4 ). Anal lobe with slight projection. Moderately coarse punctation easily visible at 100x magnification. VR 1.18. R2+3 ends 1/2 distance between R1 and R4+5. Costal extension 85 long. Brachiolum with 2 setae, R with 6 setae, remaining veins bare. Squama bare.

Legs. Spur of front tibia 48 long, spurs of middle tibia 37 and 16 long, of hind tibia 42 and 21 long, with weak denticles. Hind tibial comb with 8–9 setae. Length and proportions of leg segments:

Hypopygium ( Figs. 5, 6 ). Anal point hyaline, roughly triangular with blunt apex, 16 long, 10 wide at base. Anal point length/width 1.60. Tergite IX with 9 setae, laterosternite IX with 2 setae. Phallapodeme 75 long, transverse sternapodeme 86 wide, weakly arcuate with developed oral projection. Virga 26 long, composed of cluster of 6­7 spines. Gonocoxite 164 long. Gonostylus 70 long, with angulate subapical heel. Inferior volsella setose and present at the base of gonocoxite. Megaseta 13 long. HR 2.33, HV 1.42.

Distribution. The species is known only from the type locality in the Great Smoky Mountains National Park.

Remarks. This new species is similar in hypopygial structure to three Palaearctic species, B. cuneiformis (Armitage) , B. propinquus (Brundin) and B. scanicus (Brundin) . It differs in the following combined characters: tergite IX without cornuted projection; squama bare; setose inferior volsella present at the base of gonocoxite and different shaped crista dorsalis. Female and immature stages unknown.

Figures

FIGURES 4 – 6. Bryophaenocladius polychaetus sp. n. Holotype, male imago: 4. Wing; 5. Hypopygium, dorsal aspect; 6. Hypopygium, ventral aspect.