Protonemura bifurcata, Li, Weihai, Murányi, Dávid & Yang, Ding, 2017

Li, Weihai, Murányi, Dávid & Yang, Ding, 2017, Two new species of Protonemura (Plecoptera: Nemouridae) from China, with biogeographical notes on the genus, Zootaxa 4258 (1) : -

Protonemura bifurcata sp. n.

( Figs. 1–2 )

Type material. Holotype male ( CAU): CHINA: Taiwan, Hualian County, Bilu Mountain , 2070 m a.s.l., 28.VI.2012, leg. Lihua Wang .

Description ( Figs. 2 a, 2b). Forewing length 6.8 mm. Head dark brown; antennae dark brown, palpi brownish yellow. Pronotum slightly lighter than head, lateral margins brownish, with scattered rugosities. Legs generally brownish with yellow pattern, tarsi brown; hindleg basal half brownish yellow, distal part brown, femora generally with basal half yellow brown, followed by distinct yellow bands before brown distal fourth; these pattern less distinct in midleg and obscure in foreleg; wings evenly brownish, venation dark brown. Abdomen brown, terminal segments dark brown. Pilosity generally short but with some long hairs on terminal segments.

Male terminalia ( Figs. 1 , 2 c-2f): Hypoproct about ¼ of the width of sternum 9, basally subrectangular and apical third tapering with slightly up-curved, nipple-shaped tip; vesicle claviform, more than 2X longer than wide, mesally slightly constricted in ventral view but distinctly swollen in lateral aspect. Paraproct trilobed: inner lobe very slender and stick-like, nearly as long as outer lobe, dark brown with two distal short spines. Median lobe wide and subquadrate with triangular apex adhering to outer lobe; anterior and outer portion of the lobe mostly sclerotized. Outer lobe heavily sclerotized, basal part fused with median lobe; apex upcurved and palm-shaped with ca. 9-10 large spines. Cerci cylindrical, slightly narrowing toward tip; tip blunt, with a tiny apical nipple. Tergum VIII dark brown, anterior margin thickened, with shallow rounded indentation and several small posteriomedial spines. Tergum IX mostly well sclerotized, with thickened anterior margin, and a trapezoidal medial membranous field with many tiny spines. Tergum X sclerotized except medial longitudinal membranous concavity under epiproct with several anterolateral spinules. Epiproct long and recurved, subquadrate in dorsal view, apex rounded and with a pair of curved flagella seen in anterior, posterior and lateral views. Dorsal sclerite with a strongly sclerotized oblong base, then forming divergent lateral arms and ending barely over midlength, in lateral aspect slightly bent downwards as a slender triangular sclerite. Ventral sclerite basal half nearly paralell with dorsal sclerite, before an abrupt swelling at midlength, swelling area is forming a triangular mesoventral ridge with several small spines before inserted into the dorsal sclerite; apex extended over dorsal sclerite to form paired posteriorly directed flagella.

Female and larva: unknown.

Affinities. The epiproctal flagella and the outer paraproctal lobe of the new species places the new species in the Japanese P. orbiculata group sensu Shimizu (1998), but the ventral sclerite of epiproct differs from any member of this group, being parallel-sided with the lateral margins of dorsal sclerite at basal half in P. bifurcata (compare figs. 32–35 in Shimizu 1998 with Fig. 1 a). Protonemura bifurcata shares some similarities also to P. fansipanensis Sivec and Stark, 2009 from Vietnam, but distinctly differs with inner lobe of paraproct bearing two apical spines and median lobe wide but without an apical spine. Whereas in P. fansipanensis , inner lobe of paraproct lacks apical setation and median lobe is slender and bearing an apical spine; however, this Vietnam species appears not to be member of the orbiculata group because of vestigial (lacking?) epiproctal flagellum.

Etymology. The specific name refers to the widely bifurcate apical flagellum of the epiproct.

Figures

FIGURE 1. Protonemura bifurcata sp. n. male. a. Terminalia, dorsal view; b. Terminalia, ventral view; c. Terminalia, lateral view; d. Epiproct flagella, posterior view. e. Epiproct, lateral view; f. Paraproct, caudal view.

FIGURE 2. Protonemura bifurcata sp. n. male. a. Adult, dorsal view; b. Adult, ventral view; c. Epiproct flagella, posterior view; d. Epiproct flagella, anterior view. e. Epiproct, dorsal view; f. Epiproct, lateral view.