Filchneria dongruihangi, Chen, 2020

Chen, Zhi-Teng, 2020, Description of a new Filchneria (Plecoptera: Perlodidae), with supplementary illustrations for Taenionema japonicum (Plecoptera: Taeniopterygidae) from northeastern China, Zootaxa 4808 (2), pp. 350-364 : 351-358

publication ID	https://doi.org/ 10.11646/zootaxa.4808.2.7
publication LSID	lsid:zoobank.org:pub:3AAA1402-BED2-453B-B79F-93A1E149EB7C
DOI	https://doi.org/10.5281/zenodo.4324031
persistent identifier	https://treatment.plazi.org/id/B91B87D3-954E-7957-FF6D-FA96FCC66226
treatment provided by	Plazi
scientific name	Filchneria dongruihangi
status	sp. nov.

Treatment

Filchneria dongruihangi View in CoL sp. nov.

Figs. 2–10 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 .

Male ( Figs. 2–8 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 ). Body length ca. 14 mm, generally brown ( Fig. 2 View FIGURE 2 ). Head ( Fig. 3 View FIGURE 3 ) mostly brown; ocellar area with a diamond-shaped pale spot; lateral areas of the anterior ocellus with two transverse calluses; anterior of the head with a sub-trapezoidal pale area, expanding anteriorly; posterior area of the head pale. Antenna brown and slender, subequal in length to the abdomen. Pronotum ( Fig. 3 View FIGURE 3 ) subquadrate with obtuse corners, generally brown except for the pale, median band, the band constricted twice near anterior and posterior ends. Mesothoracic furcasterum branches reaching posterior of the furcal pits. Brachypterous ( Figs. 1 View FIGURE 1 , 4 View FIGURE 4 A–B), wing membrane subhyaline, veins pale brown; forewings length ca. 3.5 mm, hindwings length ca. 4 mm. In the forewing, the apical venation includes a small marginal net; anal area with two veins. In the hind wing, the apical net small and simple; anal area large, with eight anal branches. Legs mostly pale, joints darker.

Abdominal segments generally brown ( Fig. 5 View FIGURE 5 ). Sterna 1 completely fused with metathorax. Segments 1–3 divided into distinct terga and sterna. Posterior of terga 7–9 slightly humped and hairy; tergum 7 with two sparse patches of sensilla basiconica near posterior margin; tergum 8 with a subtriangular membranous median area which covered with several moderate spines; two kidney-shaped light spots present lateral to the membrane; posterior half of tergum 8 with two dense patches of stout sensilla basiconica ( Fig. 6 View FIGURE 6 A–B). Tergum 9 with membranous median area and lateral spots similar to tergum 8, near posterior margin with two dense patches of stout sensilla basiconica. Anterior half of tergum 10 with a membranous median area, scattered with sparse short spines; posterior half of tergum 10 moderately upcurved, covered by dense sensilla basiconica. Sensilla basiconica on terga 8–10 with similar shapes and sizes. The paraproct sclerite prolonged( Fig. 7 View FIGURE 7 A–B), wide and sclerotized basally, then constricted near base, apical half with a weakly sclerotized, subtriangular anterior expansion and a dark, finger-shaped apical projection, the anterior expansion and the apical projection divided by an obscure sinuous boundary; inner margin of each paraproct sclerite not connected basally; the eversible paraproct lobe resembling a “drumstick” ( Fig. 7 View FIGURE 7 C–F), with a broad basal cushion which covered by dense hairs and several short spines, then constricted near base and enlarged apically, surface covered with dense wrinkles and short hairs. The aedeagus ( Fig. 8 View FIGURE 8 ) completely membranous, with a low dorsomedial lobe and several small apical lobes ( Fig. 8 View FIGURE 8 A–D). From ventral and lateral views, the partially everted aedeagus of another male specimen apically with three ear-shaped large lobes surrounding a small medial lobe ( Fig. 8 View FIGURE 8 E–H). Cerci generally pale, subequal in length to the abdomen, each segment apically fringed with stout spines and long bristles.

Female ( Fig. 9 View FIGURE 9 ). Body length ca. 17 mm, color pattern similar to the male ( Fig. 9 View FIGURE 9 A–B). Macropterous; forewing length 14 mm, hindwing length 12 mm. In the forewing, the venation includes a small net near the apex; anal area with four branches. In the hind wing, the apical net small and simple; anal area large, with 11 anal branches. Sternum 8 with two anterolateral sclerites, anteromedially with a subtriangular pale area. Subgenital plate ( Fig. 9C View FIGURE 9 ) originating from half-length of sternum 8, covering half of sternum 9. The subgenital plate broad and weakly sclerotized, posterior margin mostly truncate, with a shallow median notch, the notch comprised of three small incisions, anterior area, median line and posterior margins pale, other areas weakly sclerotized. Sternum 9 with two dark spots laterally connected with lateral surfaces of the segment. Sternum 10 pale, unmodified.

Type material. Holotype male, China: Heilongjiang Province, Qiqihar City, Liuyuan Park, Nenjiang River ( Fig. 10 View FIGURE 10 ), 47.35992625 N, 123.90812588 E, 145 m, April 25, 2020, Rui-Hang Dong, Ming-Wei Li (ICJUST) GoogleMaps . Paratypes: two males and one female, same locality and data as holotype (ICJUST).

Etymology. The species is named after Mr. Rui-Hang Dong for collecting the specimens.

Diagnosis. The nearly truncate posterior margin of the female subgenital plate can easily separate the new species from almost all eastern Asian congeners which have distinctly bilobed subgenital plates with deep posteromedial notch ( Klapálek 1901, Šámal 1935, Navás 1936, Wu 1938, Zhiltzova 1971, Teslenko et al. 2010, Chen 2019a, b). The female subgenital plate of F. tau from Shaanxi Province of China is posteriorly truncate and with two posterolateral extensions (see fig. 20 in Klapálek 1912), but in F. dongruihangi , the plate has a shallow posterior notch and has no posterolateral extensions. The apically enlarged eversible paraproct lobe is similar to that of F. songi , but the broad basal cushion is absent in F. songi , and the chaetotaxy of terga 7–10 of the male differs between the two species ( Chen 2019a). Aedeagus of F. dongruihangi seems similar to F. wusuensis and F. mongolica in having several small apical lobes, but the shapes of paraproct sclerite and female subgenital plate of F. dongruihangi apparently differ from the two latter species ( Zwick 1997, Teslenko et al. 2010, Chen 2019b). In F. mongolica , the paraproct sclerite has a clear anterior margin along the finger-shaped apical projection ( Fig. 7F View FIGURE 7 ); the eversible paraproct lobe is spinulose ( Fig. 7F View FIGURE 7 ); the female subgenital plate is bilobed with a U-shaped deep notch (see fig. 9 in Teslenko et al. 2010). However, in F. dongruihangi , the paraproct sclerite has an obscure sinuous boundary separating the anterior expansion and the posterior projection ( Fig. 7 View FIGURE 7 A–B); the eversible paraproct lobe has dense wrinkles and short hairs instead of spinules ( Fig. 7 View FIGURE 7 C–E); the female subgenital plate is entire with a nearly truncate posterior margin ( Fig. 9C View FIGURE 9 ).

Remarks. The unnamed Filchneria species illustrated in Chen (2019b) was collected also from Heilongjiang Province. The two species have very similar pattern on head, pronotum and male terga 8–10, showing similar patches of sensilla basiconica on male terga 8–10 ( Chen 2019a). The two species are also somewhat similar in the shape of paraproct sclerite and eversible paraproct lobe. However, that single male is insufficient for an accurate specific comparison, its female is needed to confirm its identity.