Flavoperla ovalolobata ( Wu, 1948 )

Liu, Hao, Yan, Yanhua, Li, Weihai & Shi, Mingwang, 2020, Rediscovery of a poorly known Chinese stonefly, Flavoperla ovalolobata (Wu, 1948) (Plecoptera: Perlidae), Zootaxa 4819 (3), pp. 595-600 : 596-599

Flavoperla ovalolobata ( Wu, 1948)

( Figs. 1–5 )

Adult habitus. Biocellate. General body color light brown with dark pattern in ethanol, darker when alive. Head mostly dark brown to black except for a narrow pale area around inner margin of compound eyes and scape, dark area consisting of a large heart-shaped marking posterior to M-line and a small triangular spot forward of M-line; antennae brown, palpi pale brown; head slightly wider than pronotum ( Figs.1 , 5a ). Pronotum dark brown, rectangular, with distinct rugosities; corners obtuse. Wing membrane brownish, veins brown; legs brownish to brown but femora lighter. Abdominal segments and cerci brownish.

Male ( Figs. 1a , 2–4 ). Forewing length ca. 8.3 mm, hindwing length ca. 7.1 mm, length to tip of wings ca. 9.9 mm, alar expanse ca. 17.1 mm. Tergum 9 with a small posteromedial sclerite ( Fig. 4a ). Epiproct sclerite of tergum 10 heavily sclerotized, trapezoidal in dorsal view when the tergum is sloped, but elongate and nearly triangular in posterior view ( Fig. 4 ); the paired tergal spines closer to each other than to lateral margins of the tergum ( Fig. 2b ). Paraprocts gently curving upward and generally hook-shaped ( Fig. 2b ), robust with blunt with rounded tips ( Figs. 3b, 3d & 4b ). Hammer with basal ½ subquadrate and brown, with less sclerotized anterolateral extensions, distal portion pale, nearly triangular with a shallow lateral constriction before apex in ventral view; apex nearly parallelsided and straight in lateral view ( Figs. 2c & 2d ).

Everted aedeagus ( Figs. 3 a–3c), mostly membranous with indistinct armature. Basally with two ventrolateral lobes, between the lobes a larger, projecting basoventral lobe; medial ½ forming a quadrate lobe in lateral view before the tri-lobed apex ( Figs. 3 a–3c).

Female ( Figs. 5 a–5b). Forewing length 8.9–9.2 mm. Generally similar to males. Subgenital plate broadly rounded basally, abruptly narrowed at midpoint, apex after the constriction slightly swollen and similar to a hammer usually present in Acroneurinae; the apex darkly sclerotized with lighter medial longitudinal band. Sternum 9 sclerotized, anterior margin deeply emarginate medially. Sternum 10 slightly sclerotized.

Distribution. Presently known from Wuyi Mountains of northern Fujian Province, China.

Examined material. 1 male and 2 females ( HIST): China: Fujian Province, Nanping City, Shaowu County, Wuyishan , Nanhu Forest Farm , 409m, 2019.VI.14, light trap, N 27°32'38'', E 117°29'3'', Raorao Mo, Xiuhong Shi & Weihai Li ; 2 females, China: Fujian Province, Nanping City, Wuyishan, Sangang , 735 m, 2009.VII.12, light trap, N 27°44'57'', E 117°40'45'', Li Shi & Xiaoyan Liu .

Remarks. The specific identity of F. ovalolobata is not without some doubt. The above specimens are generally similar to the Wu (1948) description of this taxon, except the size of our specimens are much smaller. We still consider the above specimens as topotypes.A phylogenetic revision of the taxa currently included in Flavoperla and Gibosia is required to confirm generic concepts and ultimately, a neotype could be designated for F. ovalolobata as the holotype is lost. The brownish body color is similar to Gibosia but the color is usually not decisive for the generic distinction in the Perlidae . The following features of our material indicate that this species more likely belongs to Flavoperla following the present generic concept, smaller body size, no separation between tergum 10 and the epiproct, the vesicle only weakly separated from sternum 9 in the male, and the deeply incised posterior margin of sternum 9 in females.

Figures

FIGURE 1. Flavoperla ovalolobata (Wu, 1948). a. Adult male, dorsal view.

FIGURES 2. Flavoperla ovalolobata (Wu, 1948). (male). a. Head and pronotum, dorsal view. b. Terminalia, dorsal view. c. Terminalia, lateral view. d. Sternum 9, ventral view.

FIGURES 3. Flavoperla ovalolobata (Wu, 1948). (male). a. Aedeagus, ventral view. b. Aedeagus, dorsal view. c. Aedeagus, lateral view. d. Cleared terminalia, caudal view.

FIGURE 4. Flavoperla ovalolobata (Wu, 1948). (male). a. Cleared terminalia, dorsal view. b. Cleared terminalia, posterior view.

FIGURE 5. Flavoperla ovalolobata (Wu, 1948). (female). a. Head and pronotum, dorsal view. b. Terminalia, ventral view.