Largusoperla reni Chen & Wang, 2019

Chen, Zhi-Teng & Wang, Bo, 2019, Review of the fossil genus Largusoperla (Plecoptera: Perlidae): Annotated checklist, taxonomic identification, and description of a new species, Zootaxa 4565 (2), pp. 281-291 : 285

Largusoperla reni Chen & Wang , sp. nov.

Figs. 3–5 .

Description. Macropterous; body length (excluding antennae and cerci) ca. 12.5 mm, slender, generally brown ( Fig. 3 ).

Head ( Fig. 3 ): Head elliptical, with a dark stigma covering the three ocelli and the anterior half of head, compound eyes dark. Antennae dark brown, with over 50 segments. Maxillary palp slender and five-segmented, with a shortened apical segment, longer than the three-segmented labial palp.

Pronotum ( Fig. 3 ): Pronotum narrower than head, oval and mostly brown. Mesothorax and metathorax strongly sclerotized, nearly as wide as pronotum. Legs mostly brown; tibia dark, two tibia spurs present; first two tarsal segments shortest with conspicuous euplantulae.

Left forewing ( Fig. 4 ): Wings hyaline, veins dark brown. Forewing length ca. 12.0 mm; ScP reaches RA beyond ra-rp; 11 crossveins and the single h vein present in the costal area; two crossveins present in the apical area; RP originates from basal ¼ of RA and with four branches; M forked at near apical ¼ of the wing length, MA partially fused with RP, MP partially fused with the four-branched CuA; CuP and AA1 simple, AA2 with three branches; area between M and CuA with eight crossveins; area between CuA and CuP with five crossveins.

Abdomen ( Figs. 3 , 5 ): Abdomen slender, near half the length of the body, with dark lateral and ventral marks; posterolateral margins of each segment not extended. Sternum 9 extended backwards, posteromedially with a rounded hammer; an oval membranous area presents on posterior half of sternum 8 and anterior half of sternum 9; a pair of elliptical membranous area present beside the hammer. Paraprocts completely sclerotized, elongated and kidney-shaped with obtuse apices, length twice the width; each paraproct with a convex inner margin and a concave outer margin; basolateral part of right paraproct with a notch, which may be the damage caused by fossilization. Cercus hairy, with about 8 segments.

Type material. Holotype male, No. NIGP169678 . This specimen is well preserved. Wings are overlapped so only the left forewing is visible.

Etymology. The new species is named for Professor Ren Dong (Capital Normal University, China) for his great contributions to the knowledge of fossil insects.

Syninclusions. Unidentified Psocodea, Hymenoptera, and Diptera.

Remarks. The body color, wing venation and terminalia structures, especially the ventral hammer and large paraprocts of the new species indicate its taxonomic inclusion in genus Largusoperla . The shortened apical segment of maxillary palp, the rounded hammer, and the long kidney-shaped paraproct of L. reni appears similar to those of L. billwymani . However, L. reni can be distinguished from L. billwymani by CuA and AA2 with more branches in forewing, M fused with RP and CuA, and by the completely sclerotized paraprocts.

Figures

FIGURE 3. Largusoperla reni, sp. nov. Adult habitus, dorsal view.

FIGURE 4. Largusoperla reni, sp. nov. Left forewing, dorsal view; fusion between veins indicated by red lines.

FIGURE 5. Largusoperla reni, sp. nov. Photograph and reconstruction of terminalia, ventral view.