Flavoperla basomarginata Chen, 2019

Chen, Zhi-Teng, 2019, On the identity of the genus Flavoperla (Plecoptera: Perlidae), with description of a new species in southwestern China, Zootaxa 4613 (1), pp. 127-134 : 128-129

Flavoperla basomarginata Chen , sp. nov.

Figs. 1–7

Adult habitus. Biocellate. Body color generally pale brown ( Fig. 1 ). Head pale with obscure M-line; two oval callosities located laterad to ocelli ( Fig. 1B ). Antennae pale brown, length subequal to half of the body length. Maxillary palpi pale, four-segmented with apical segment shortest; labial palpi three-segmented with apical segment shortest ( Fig. 1C ). Pronotum sub-trapezoidal with brown sutures and rugosities, anteromedial margin slightly protruded; meso- and metanota pale. Wings hyaline, veins brown. Legs generally pale, tarsal claws darker; two tibia spurs present. Abdominal segments generally pale, each segment with posterolateral setae. Cercus brown, about twelve-segmented, each segment with strong setal whorls.

Male. Body length ca. 15.0 mm; forewings length ca. 16.5 mm, hindwings length ca. 14.0 mm. Abdominal tergum 10 with a pair of subtriangular, posterolateral spines on either side of median epiproct sclerite; epiproct sclerite “butterfly-shaped” with short wide stem and short arms, apex blunt; darker plots of tergum 10 present anterior to arms of epiproct sclerite ( Figs. 2 A–B). Paraprocts claw-shaped, slightly upcurved, basolateral margins strongly sclerotized and connected with base of cerci ( Fig. 3 ). Sternum 9 with a long bell-shaped hammer located medially; the hammer projected reaching posterior margin of sternum 9, boot-shaped from lateral view, mostly membranous with sclerotized apex ( Figs. 3 –4). The aedeagus generally membranous (Figs. 4C, 4D), ventrally with two oval lobes connected to the broad base, apex rounded, narrower than base and with two lateral spines; the aedeagus ventroapically with an arched sclerite, which is the ventral apex of the dorsal heart-shaped lobe; two obscure dorsal lobes also present in half-length of the aedeagus.

Female. Body length ca. 17.0 mm ( Fig. 1D ); forewings length ca. 18.0 mm, hindwings length ca. 15.0 mm. Subgenital plate semielliptical, originated from sternum 8, reaching midpoint of sternum 10 (Fig. 5). Sternum 9 embedded posteromedially. Paraprocts subtriangular in shape.

Type material. Holotype male: China: Sichuan Province, Chongzhou City, Anzihe Nature Reserve, Shaoyaogou , a fast-flowing small stream along the road ( Fig. 6 ), 1598 m, 30°47.95′ N, 103°122.70′ E, 19 June 2016 (ICJUST) . Paratypes: 19 males and 3 females, same locality and data as holotype (ICJUST) .

Etymology. The specific epithet refers to the sclerotized basal margin of the male paraproct.

Diagnosis. The new species is similar to F. dao Stark & Sivec, 2008 , F. hmong Stark & Sivec, 2008 and F. pallida Stark & Sivec, 2008 from Vietnam, but the male can be distinguished from F. dao by the larger spines on tergum 10, the basolaterally sclerotized paraprocts, and by the much larger, laterally boot-shaped hammer (see figs. 2–4 in Stark & Sivec 2008). Males of F. basomarginata can be separated from F. hmong by the unpigmented head, the butterfly-shaped epiproct sclerite, and by the shorter basal stem of the hammer (see figs. 6–9 in Stark & Sivec 2008). The new species can also be separated in the male from F. pallida by the larger spines on tergum 10, the butterfly-shaped epiproct sclerite, the much larger, boot-shaped hammer, and by the unmodified female subgenital plate (see figs. 12–15 in Stark & Sivec 2008). The following key can be used to separate the known males of species of Flavoperla . The aedeagus of the new species appears different from that of F. pallida (see fig. 16 in Stark & Sivec 2008). However, comparison of aedeagi among all Flavoperla species is currently impossible due to lack of comparable data.

Figures

FIGURE 1. Flavoperla basomarginata sp. nov. A. male habitus, dorsal view; B. male head and pronotum, dorsal view; C. male habitus, ventral view; D. female habitus, dorsal view.

FIGURE 2. Flavoperla basomarginata sp. nov. A. male terminalia, dorsal view; B. drawing of male terminalia, dorsal view. ST9: sternum 9.

FIGURE 3. Flavoperla basomarginata sp. nov. A. Male terminalia, ventral view; B. drawing of male terminalia, ventral view; C. male hammer, ventral view. T10: tergum 10.

FIGURE 6. Habitat of Flavoperla basomarginata sp. nov. in Shaoyaogou, Anzihe Nature Reserve, Sichuan Province, China.

FIGURE 7. Geographical distribution of Flavoperla species based on literature records. Numbers of F. hmong and F. pallida are reduced in size to fit in the same locality.