Tyloperla bilobata, Mo & Wang & Li, 2020

Mo, Raorao, Wang, Guoquan & Li, Weihai, 2020, A new species of Tyloperla (Plecoptera: Perlidae) from Guangxi, China, with a redescription of the male of T. sinensis Yang & Yang, 1993, Zootaxa 4763 (1), pp. 109-116 : 109-113

Tyloperla bilobata sp. nov.

( Figs. 1–3 )

Male habitus ( Figs. 1 a–1b). Forewing length ca. 13.0 mm, hindwing length ca. 11.5 mm. General color dark brown. Triocellate, anterior ocellus smaller. Head slightly wider than pronotum, brown, with a dark brown ocellar patch expanded around front of ocelli and callosities and extending to M-line and a dark brown subtriangular stigma; com- pound eyes dark; antennae dark brown. Pronotum brown, rectangular with distinct dark brown rugosities, anterior corners pointed but posterior corners obtuse; wings membrane brownish, veins dark brown; legs mostly dark brown, basal half of femora pale brown; cerci dark brown.

Terminalia ( Figs. 1c , 2 a–2c). Posterior margin of tergum 7 with a small patch of sensilla basiconica. Tergum 8 with a small raised sclerotized lobe medially covered with a small field of sensilla basiconica. Membranous portion of tergum 9 with a mesal patch of sensilla basiconica set on a low sclerotized subtrapezoidal mound. Hemitergal processes of tergum 10 acute, finger-like and strongly curved inward; process in lateral aspect subtriangular; basal callus rounded.

Aedeagus ( Figs. 2d & 3 ). The everted aedeagus S-shaped, mostly membranous, with a sharp point; basal sclerite well developed. Aedeagal tube with a pair sclerotized low dorsomedial lobes, and a pair of long, sharply curved dorsolateral lobes in the apical part armed with small triangular spines; apical half covered with a subtriangular patch of densely clustered, small spines but interrupted dorsally and with three larger triangular medially spines at ventral surface. Aedeagal sac strongly curved ventrad armed with stout triangular spines and apical spines denser; apical third offset by a distinct groove.

Female. Unknown.

Type Material. Holotype male ( CAU), China: Guangxi Zhuang Autonomous Region, Fangcheng, Jinhuacha Nature Reserve , 21°76,09’ N, 108°43,49’ E, 2013.V.15, Liu Xingyue.

Etymology. The name refers to a pair of long dorsolateral lobes in the apical part of aedeagal tube. Latin “bi-” means double, and “lobus” means lobes.

Distribution. China (Guangxi).

Remarks. The new species is apparently most similar to T. illiesi Stark & Sivec, 2005 from Vietnam in having a similar head maculation, terminalia , and aedeagus, but may be separated from T. illiesi by strongly incurved hemitergal processes of tergum 10, aedeagus with a smaller subtriangular patch of small spines at midlength and the tip armed with stout spines except apical spines denser, and two pairs of lobes of the aedeagus are on the same side. In T. illiesi , the hemitergal processes of tergum 10 curved outward at tip, apical half of aedeagus armed with dense spines, and two pairs of lobes of the aedeagus are on different surfaces.

Figures

FIGURE 1. Tyloperla bilobata sp. nov. (male). a. Adult of male, dorsal view. b. Head and pronotum, dorsal view. c. Terminalia, dorsal view.

FIGURE 2. Tyloperla bilobata sp. nov. (male). a. Terminalia after being cleared, dorsal view. b. Terminalia after being cleared, lateral view. d. Aedeagus, lateral view.

FIGURE 3. Tyloperla bilobata sp. nov. (details of male aedeagus). a. Aedeagus, oblique lateral view. b. Aedeagal sac, dorsal view. c. Aedeagal sac, ventral view. d. ventral curve of aedeagal sac, top view. e. Dorsomedial lobes of aedeagal tube, dorsal view.