Neofilchneria wanglanga Chen, 2019

Chen, Zhi-Teng, 2019, The discovery of a new species of Neofilchneria (Plecoptera: Perlodidae) from China and a review of the genus, Zootaxa 4586 (3), pp. 562-570 : 564-568

Neofilchneria wanglanga Chen , sp. nov.

Figs. 2–8 .

Adult habitus ( Figs. 2 , 3 ). Body generally dark brown. Head mostly covered by a brown stigma, posterolateral margins with two fringed pigmented sclerotized areas. Triocellate, but anterior ocellus largely reduced. Antenna brown and slender, subequal in length to the body. Maxillary palps slender, five-segmented with a short apical segment; labial palps shorter, three-segmented with a short apical segment. Submental gills long and upcurved. Pronotum rugose and generally dark brown except for the pale median band, subtrapezoidal with angled corners; anterior and posterior margins of pronotum expanded longitudinally. Meso- and metanota generally dark brown. Macropterous; wings pale brown, veins brown. Legs generally pale brown, apex of femur, base and apex of tibia, and tarsus dark brown; two tibial spurs present. Abdominal segments generally brown, terminal segments pale. Cercus slender, length near two-thirds of the body, generally pale but apical half of each segment brown.

Male ( Figs. 2–6 ). Body length 16.0 mm; forewing length 14.0 mm, hindwings length 12.0 mm. In the forewing, the venation includes an irregular net near the apex; five crossveins present between C and Sc; RP with three apical branches; five crossveins present between M and CuA; five crossveins present between CuA and CuP; AA1 forked; AA2 with three branches. In the hind wing, the apical net more complex than in the forewing; RP with seven apical branches; anal area large, with 12 anal branches.

Abdominal tergum 9 with a depressed, membranous, pale median area. Sternum 9 unmodified. Tergum 10 divided into two finger-shaped hemiterga, generally pale but anterolaterally dark brown. The hemitergal lobes in dorsal view are elongated and directed anteromedially, reaching each other; in lateral view, the hemitergal lobes are raised. Anterior surface of the hemitergal lobes covered with stout spines. Median area of hemiterga concave and membranous with a deep median slit parallel to two dark sclerotized bands, the bands extended backwards until covered by the subtriangular sclerotized paraprocts; a V-shaped sclerite originating from the apex of the lever arm present above the bands; the slit extended back to base of epiproct. Epiproct elliptical in dorsal view, anterior margin notched; in lateral view, the epiproct is stalked, claw-shaped and pointed, margins fringed with short setae, posterior half depressed; a dark, long lever arm present inside the membranous pouch, apparently hinged, apically with a rounded membrane. Median area of sternum 10 pale brown, posteriorly extended into a truncate apex.

Aedeagus was not everted when the male was alive, after NaOH treatment of the terminalia of a preserved male, the aedeagus appears as a simple structure, membranous and oblong, without distinct sclerotized patterns of setae or spines.

Female ( Fig. 7 ). Body length 18.0 mm, generally color pattern similar to male. Subgenital plate originating from posterior margin of sternum 8, covering two-thirds of sternum 9. The subgenital plate long, the parabolic apex with a deep V-shaped notch; the lateral lobes subtriangular and slightly hooked. Sternum 9 generally pale, laterally with two dark brown circular spots. Paraprocts subtriangular from ventral view, slightly upcurved.

Type material. Holotype: male, China: Sichuan Province, Mianyang City, Pingwu County, Wanglang National Nature Reserve , Muyangchang headquarters ( Fig. 8 ), 2590 m, 32.96 N, 104.10 E, 20 June 2016 (ICJUST) . Paratypes: one male and two females, same date and locality as holotype (ICJUST).

Etymology. The species is named after the type locality, Wanglang National Nature Reserve. Wanglang National Nature Reserve is located near Huanglong Valley and Jiuzhaigou Valley. The Reserve was established in 1965 to protect rare wildlife, especially the giant pandas and their habitat.

Remarks. The new species resembles the other two species, but can be distinguished by the elongated hemitergal lobes, the elliptical and apically notched epiproct, and by the hinged lever arm apically with a rounded membranous structure (see fig. 13 in Kimmins 1947 and fig. 23 in Zwick & Sivec 1980). When compared with N. uncata , the female of the new species exhibits a much longer subgenital plate which has a deep V-shaped notch rather than the broad shallow excision in N. uncata (see fig. 13E in Kimmins 1947).

To date, a diverse of stonefly assemblage has been found in Wanglang National Nature Reserve, including N. wanglanga (Perlodidae) described herein, Sweltsa hamula Chen & Du, 2017 (Chloroperlidae) , Isocapnia anguis Chen & Du, 2017 (Capniidae) , Cryptoperla dui Sivec, 2005 (Peltoperlidae) , Soliperla wanglanga Huo & Du, 2017 (Peltoperlidae) , and other unpublished species of Nemouridae , Leuctridae Chloroperlidae and Perlidae (Chen & Du 2017a, 2017 b, Huo & Du 2017, 2018). Tourism and its supporting infrastructure is a major industry of this area and it is encouraged that the streams of this preserve be monitored to protect water quality.

Figures

FIGURE 2. Neofilchneria wanglanga sp. nov. A. male habitus, dorsal view; B. male habitus, ventral view. Scale bar is 1.0 mm.

FIGURE 3. Neofilchneria wanglanga sp. nov. A. male head and pronotum, dorsal view; B. male head and pronotum, ventral view. Scale bar is 1.0 mm.

FIGURE 4. Neofilchneria wanglanga sp. nov. A. right forewing, dorsal view; B. right hind wing, dorsal view. Scale bar is 1.0 mm.

FIGURE 5. Neofilchneria wanglanga sp. nov. A. male terminalia before NaOH treatment, dorsal view; B. drawing of male terminalia, dorsal view; C. male terminalia after NaOH treatment, dorsal view; D–F. male terminalia, lateral view; G. drawing of male epiproct, lateral view. Scale bar is 1.0 mm.

FIGURE 6. Neofilchneria wanglanga sp. nov. A. male terminalia, cephalic view; B. lever arm, cephalic view; C. lever arm, lateral view; D. lever arm, ventral view; E. male terminalia after NaOH treatment, ventral view; F. male terminalia before NaOH treatment, ventral view.

FIGURE 7. Neofilchneria wanglanga sp. nov. A. female habitus, dorsal view; B. female terminalia, ventral view.

FIGURE 8. Neofilchneria wanglanga sp. nov. Type locality: Muyangchang headquarters, Wanglang National Nature Reserve, Pingwu County, Mianyang City, Sichuan Province, China.