Mesonemoura dilatata Du & Ji, 2015

Du, Yu-Zhou, Ji, Xiao-Yu & Wang, Zhi-Jie, 2015, Description of three new Chinese species of the genus Mesonemoura (Plecoptera: Nemouridae), Florida Entomologist 98 (1), pp. 130-130 : 130

Mesonemoura dilatata Du & Ji , sp. nov. ( Figs. 1–4 )

MATERIAL EXAMINED

HOLOTYPE 3, CHINA, Tibet, Leiwuqi county, Jiasangka township , 25-VI-2009, N 31° 52.494' E 96° 17.573', 3,722 m asl, Leg. Qian Yu-Han . PARATYPES, 2 33, the same data as holotype.

1 School of Horticulture and Plant Protection and Institute of Applied Entomology, Yangzhou University, Yangzhou 225009, China

2 Department of Horticulture, Suqian College, Suqian 223800, China

MALE

Head and antennae dark brown; pronotum dark brown, transverse oblong, with rugosities. Wings hyaline, veins brown. Legs brown, the middle of femora slightly brown.

Forewing length 6.3-6.5 mm, hind wing length 5.3-5.4 mm. Tergum 9 ( Fig. 2 ) slightly sclerotized, with a small, asymmetrical notch mid-posteriorly, bearing several spinules posteriorly. Tergum 10 sclerotized, with several spinules each side of middle line. Hypoproct ( Fig. 1 ) broad basally, abruptly tapering toward the apex; vesicle long, more than half length of hypoproct, length 3 × width, ventral membranous, but slightly sclerotized dorsally, sclerotized laterally. Paraprocts ( Figs. 1, 3 ) divided into 3 lobes; inner lobe small, slightly sclerotized, fused with middle lobe; median lobe broad basally, slightly sclerotized, branched into 2 portions, inside portion of median lobe membranous, bearing many hairs, fused with outer lobe, another portion sclerotized, slender, short- er than membranous portion; outer lobe slender, sclerotized, basal part recurved along basal of cerci, other part fused with membranous portion of median lobe. Epiproct ( Figs. 2, 4 ) long and narrow; dorsal sclerite mostly slightly sclerotized, apical portion membranous, extending over onto ventral sclerite; lateral sclerite slender, sclerotized; ventral sclerite slightly sclerotized, broad basally, tapering towards apex, apical portion inserted between folds of dorsal sclerite, the apex extended distally forming a long flagellum; the flagelliform projection sclerotized, slender, with a swollen membranous apex, length of the flagellum about 1.5 × length of the epiproct; epiproct ventral sclerite with 2 rows of spinules.

FEMALE

Unknown.

DISTRIBUTION

CHINA (Tibet Autonomous Region).

ETYMOLOGY

The Latin “ dilatata ” refers to the flagelliform projection with a swollen membranous apex.

REMARKS

This species is characterized by the flagellum of the epiproct being long and curved, forming a swollen membranous apex. The new species is close to M. spiroflagellata ( Wu 1973) in having the median lobe branched into 2 portions. But in M. spiroflagellata , the sclerotized portion is equal to the membranous portion, ventral sclerite of epiproct without spines, and the apex of flagellum narrow.

Figures

Figs. 1–4. Mesonemoura dilatata Du & Ji, sp. nov. 1. Male terminalia, ventral; 2. Male terminalia, dorsal; 3. Male terminalia, lateral; 4. Male epiproct,ventral.