Amphinemura annulata Du & Ji

Ji, Xiao-Yu, Du, Yu-Zhou & Wang, Zhi-Jie, 2014, Two new species of the stonefly genus Amphinemura (Insecta, Plecoptera, Nemouridae) from China, ZooKeys 404, pp. 23-30 : 24-25

Amphinemura annulata Du & Ji sp. n. Figs 1-6

Material examined.

Holotype ♂ from China, Zhejiang Province, Mt. Tianmu, 300m, 18-20 Mar. 2006, leg. Wang Zhi-Jie, Sun Yun. Paratypes 30♂♂, the same details as holotype; 1♂, Shanxi Province, Lishan Natural Reserve, 1222m, 24 Aug. 2012, leg. Shi Fu-Ming; 1♂, Shaanxi Province, Houzhenzi, Upriver of Hougou, 26 May 1995, leg. Du Yu-Zhou; 1♂, Shaanxi Province, Foping County, East River, 1240m, 25 Sept. 1996, leg. Xing Lian-Xi; 1♂, Guizhou Province, Maolan City, Dongkuang, 22 Oct. 1996, leg. Li Zi-Zhong.

Adult habits.

Head and antennae brown, pronotum light brown, subquadrate, angles bluntly rounded, anterior margin wider than posterior margin, with lightly rugosities. Legs brown. Wings hyaline, light brown, veins brown.

Male.

Forewing length 7.7-8.2 mm, hind wing length 6.6-6.8 mm. Tergum 9 weakly sclerotized, with a small mid-posterior indention, and bearing a large bundle of tiny spines medially. Tergum 10 weakly sclerotized, with a rounded concavity below epiproct, bearing several spines on lateral margin, and a small triangular projections extruding from the base of the concavity, which is more distinct in lateral view (Figs 1 and 3). Hypoproct narrow basally, extending at midpoint and tapering with a blunt rounded tip, bulging before apex, which is more distinct in lateral view; vesicle slender, four times longer than wide (Figs 2 and 3). Paraproct divided into 3 lobes; inner lobe weakly sclerotized, thin and long, about half length of median lobe; median lobe broad basally, mostly membranous, with a long sclerotized band in its outer margin, apically curved inwards and forming an annular projection, bearing many tiny dense spines on the projection; outer lobe sclerotized, short, equal length to inner lobe (Fig. 4). Epiproct elongated, dorsal sclerite sclerotized basally, apical portion weakly sclerotized, taking up half of the dorsal sclerite, forming a small cavity at tip (Fig. 5); in lateral view, slender, well sclerotized pair of large lobes extending to ventral surface from midpoint (Fig. 3); ventral sclerite forming a triangular keel, which is more distinct in lateral view, bearing several black spines ventrally, tip of the ventral sclerite rising from the tip cavity of dorsal sclerite (Fig. 6).

Female.

Unknown.

Etymology.

The Latin “annulata” refers to median lobe of paraproct forming an annular projection pointing inwards.

Diagnosis.

This new species is similar to Amphinemura tricintusidens Wang & Zhu, 2007 (in Wang et al. 2007). Both species having the dorsal sclerite of the epiproct with an apical cavity, but the new species can be separated from the latter by the form of the ventral sclerite of the epiproct and the median lobe of the paraproct. In Amphinemura annulata sp. n., the ventral sclerite forming a triangular keel, bearing several black spines ventrally, whereas in Amphinemura tricintusidens , the ventral sclerite of the epiproct forms two heavily sclerotized sclerites which fused at the apex, each bearing two rows of denticles on the surface of the sclerotized sclerites. The median paraproct lobe of Amphinemura annulata sp. n. is mostly membranous, its outer margin sclerotized to form a long sclerotized band, and forming an annular projection pointing inwards bearing many tiny dense spines on the projection, In Amphinemura tricintusidens , the median lobe is sclerotized, tapering medially, with a darkly sclerotized rounded tip at the apex, and 3 or 4 dentations surrounding one side of the tip.