Pinguisoperla yangzhouensis, Chen, 2018

Chen, Zhi-Teng, 2018, Pinguisoperla, a new fossil genus of Perlidae (Insecta: Plecoptera) from mid-Cretaceous Burmese amber, Zootaxa 4425 (3), pp. 596-600 : 597-598

Pinguisoperla yangzhouensis Chen, sp. nov.

Figs. 1–4 .

Diagnosis. As for the genus.

Description. Macropterous; body length (excluding antennae and cerci) ca. 10 mm, generally dark ( Fig. 1 ). Dorsal head and thorax of the specimen are covered by cracks of the amber; apices of antennae and wings are not preserved; dorsal abdomen is covered by wings; ventral abdominal tip slightly decayed, whose detailed structure is unclear.

Head ( Figs. 1 , 2 ): Head inserted in prothorax, dark brown and sub-quadrate except for the dark, bulbous compound eyes; ocelli invisible. Antenna filiform, at least 24-segmented, each segment almost dark except for the paler apices. Maxillary palp four-segmented, two basal segments longest, third segment slightly thinner and shorter, apical segment shortest and thinnest, about half length of the third segment. Labial palp three-segmented, median segment longest, apical segment shortest and thinnest, about 2/3 length of the median segment.

Thorax ( Figs. 1 , 2 ): Prothorax much narrower than head, but subequal in length; pronotum dark, trapezoidal with acute corners, anterior margin wider than posterior margin. Mesothorax and metathorax unclear, but strongly sclerotized and wider than prothorax. Legs mostly dark; forelegs shortest, hindlegs longest; femur subequal in length with tibia in forelegs and midlegs, but shorter than tibia in hindlegs; tibia ventrally with two subapical spurs; tarsus three-segmented, two basal segments shortest, subequal in size and with conspicuous euplantulae, apical segment slender and with long apical bristles; claws simple and pointed.

Wings ( Figs. 1 , 3 ): Apex of left forewing lost, estimated length ca. 11 mm. ScP not clear; at least five crossveins present between ScP and the anterior margin. RP originated from basal 1/3 of RA and with three branches. M simple, not forked. Cu forked to CuA and CuP, CuA with four branches; CuP simple; area between M and CuA with six crossveins; area between CuA and CuP with six crossveins. AA1 simple, AA2 forked. Hind wings invisible.

Abdomen ( Figs. 1 , 4): Abdomen dark, near half the length of the body. Sternum 9 darkly sclerotized, posterior margin distinctly extended backwards, median area paler and decayed, unclear, perhaps with specific structures. Paraprocts invisible, not well developed; abdominal tip triangular in shape. Cercus hairy, with about 7 segments; first basal segment strongly sclerotized, enlarged and elongated, curved outward and backward; several subsequent segments still thick but gradually tapering to the hairy apex; each cercal segment subapically fringed with long setae.

Type material. Holotype male, an almost complete specimen in a piece of mid-Cretaceous Burmese amber from Kachin, Hukawng Valley (26°20´N, 96°36´E) of northern Myanmar (98.79 ± 0.62 Ma). The holotype is deposited in the Chen Amber Collection (No. CZT-PLE-MA1), Yangzhou, China .

Etymology. The species is named after Yangzhou City, where the author has studied and worked for nearly ten years.

Syninclusions. Plant remains, including leaves and twigs.

Figures

FIGURE 1. Pinguisoperla yangzhouensis, sp. nov. (A) Adult habitus, ventral view; (B) Reconstruction of adult habitus, dorsal view.

FIGURE 2. Pinguisoperla yangzhouensis, sp. nov. (A) Head and pronotum, ventral view; (B) Antennae and palpi.

FIGURE 3. Pinguisoperla yangzhouensis, sp. nov. Reconstruction of left forewing, dorsal view.