Plesioblattogryllus aristovi, HUANG & NEL, 2023

HUANG, DI-YING & NEL, ANDRÉ, 2023, A third species of Plesioblattogryllus Huang et al., 2008 discovered in the Middle- Upper Jurassic Daohugou Beds (Insecta: Plesioblattogryllidae), Palaeoentomology 6 (2), pp. 191-197 : 192

Plesioblattogryllus aristovi sp. nov.

( Figs 1 , 2 )

Material. Holotype NIGP201823 (a complete wing), housed in the Nanjing Institute of Geology and Palaeontology, Nanjing, China.

Etymology. Named in honor of late Dr. Daniil S. Aristov, in recognition of his important contribution to palaeoentomology.

Diagnosis. Space between stem of MA and first branch of RP broad; RP posterior branches distally forked; first RP fork located far distad MA origin; CuA1 with two main branches; PCu2 with five branches; wing very long and distinctly slender (wing 50 mm long, ratio wing length/width at apex of CuA = 4.13).

Type locality and horizon. Xiayingzi locality of the Daohugou Village , Wuhua Township , Ningcheng County, Chifeng City , Inner Mongolia, NE China; Middle-Late Jurassic , very close to the Middle and Late Jurassic boundary .

Description. Wing 48.5 mm long, 11.5 mm wide; anterior margin straight; costal area equal in width to subcostal area at base of RP and very slightly narrower than subcostal area in distal third of wing; costal area in distal half of wing with short and straight crossveins; ScP ending close to apex of RA; ScP, stem of R (i. e., R before its fork into RA and RP) and RA nearly straight; RA nearly aligned with stem of R; a secondary longitudinal vein emerging from R, remaining closely parallel to it, and ending at one third of wing length (after separation of RP), with crossveins present between this vein, ScP, and R respectively; base of RP in basal third of wing, well-separated from MA+CuA; RP posteriorly branched, with five main branches; base of M appressed to that of R but probably free; M fused with CuA (into M+CuA) very close to wing base; MA and MP branching-off CuA in separate stems; MA, MP and CuA1 forked; CuA2 simple; CuA forks into CuA1 and CuA2 immediately distad base of MP; CuP+(PCu1) simple and straight; PCu2 with five branches; anal vein weak and forked; last branch of PCu2 and first branches of anal vein curved apically; area between M+CuA and CuP+(PCu1) broad, with sigmoidal crossveins; plica prima anterior range about 45º with wing anterior margin, a net of irregular cells is visible posterior to the anal veins.

Figures

FIGURE 1. Plesioblattogryllus aristovi sp. nov., holotype NIGP201823, Photographs. A, General habitus with vertical light. B, General habitus with lateral light. Scale bars = 5 mm (A, B), 2 mm (C, D).

FIGURE 2. Plesioblattogryllus aristovi sp. nov., holotype NIGP201823, wing base. Scale bar = 1mm.