Neoperla erecta, Stark & Sivec, 2008

Stark, Bill P. & Sivec, Ignac, 2008, New Species And Records Of Neoperla (Plecoptera: Perlidae) From Vietnam, Illiesia 4 (3), pp. 19-54 : 27-28

Neoperla erecta sp. n.

( Figs. 23‐25 )

Material examined. Holotype ♂ from Vietnam, Lao Cai, Muong Hoa Ho River , 5‐12 May 1995, D. Currie, B. Hubley, J. Swann, ROM 956007 ( ROM).

Adult habitus. Biocellate. Head pale except for quadrate spot over ocelli and obscure chevron centered on anterior of frons ( Fig. 23 ). Wing membrane, veins and legs pale.

Male. Forewing length 9.5 mm. Process of tergum 7 small, rounded and margined with spines. Mesal field of tergum 8 bearing a sparse patch of sensilla basiconica; mesal field of tergum 9 bearing long setae and mixed sensilla basiconica ( Fig. 24 ). Hemitergal lobes broad basolaterally and narrow at apex; hemitergal processes long, slender and curved near midlength. Aedeagal tube plump and weakly sclerotized; aedeagal sac longer than tube, erect, strongly directed ventrad, and originating in a preapical position ( Fig. 25 ). Sac armed over most of surface with small triangular spines; spines larger on lateral humps at midlength and in patch near apex.

Female. Unknown.

Larva. Unknown.

Etymology. The species name refers to the upright (but ventrally directed) orientation of the aedeagal sac.

Diagnosis. The aedeagus of N. erecta is similar to that of N. melanocephala (Navás) , a species from Myanmar redescribed by Zwick (1988). That species, however, is very dark and the aedeagal sac is covered rather completely by small spines of uniform size except for slightly larger ones in a partial basal ring. Among known Vietnamese species the aedeagus is generally similar to that of N. nebulosa but these species are fundamentally different in the pattern and shape of male tergal lobes in addition to conspicuous differences in aedeagal sac armature.

Figures

Figs. 23‐25. Neoperla erecta. 23. Head and pronotum, 24. Male terminalia, 25. Aedeagus.