Phtanomiamia gui, Chen & Ren & BØthoux, 2020

Chen, Lu, Ren, Dong & BØthoux, Olivier, 2020, A new, rare and small “ lobeattid ” species (Insecta: Archaeorthoptera) found at Xiaheyan (Pennsylvanian; Ningxia, China), Fossil Record 23 (1), pp. 71-74 : 73

Phtanomiamia gui sp. nov.

Material

Holotype only, CNU-NX1-324, deposited at the CNU.

Etymology

The species name is dedicated to Junjie Gu, for his contributions to fieldwork at Xiaheyan and to the systematics of Orthoptera.

Diagnosis

Forewing: ScP– R /RA area broad (at its broadest, broader than the area between the anterior wing margin and ScP); first fork of M in a distal position (distal to the second fifth of wing length, basal to wing mid-length); CuA + CuPa branched shortly after the fusion of CuA and CuPa; CuA with a distinct, free portion between its divergence from M + CuA and its fusion with CuPa.

Description

Holotype specimen (CNU-NX1-324): negative imprint of an isolated, left forewing, apex missing; preserved length about 12.2 mm, estimated length about 13.8 mm, maximum width 4.2 mm; ScA present, short; ScP– R /RA area broader than area between anterior wing margin and ScP; area between the anterior wing margin and ScP/ScP + RA with strong cross-veins, mostly oblique and simple, reticulated near the wing base; ScP reaching RA slightly basal to the second third of wing length; RA/RP fork slightly basal to the first third of wing length; RA simple; RA and RP close and parallel until wing mid-length, where both veins diverge; RP simple for 4.7 mm, posteriorly pectinate (as preserved), with five branches preserved, the anterior-most one reaching RA; M weak, simple for 3.7 mm before it forks into MA and MP; MA simple (as preserved), MP with two preserved branches (it probably possessed 3); CuA 0.5 mm long before its fusion with CuPa; CuA + CuPa forked immediately after the fusion of CuA and CuPa; CuA + CuPa with a total of five branches (2, 3); CuPb simple and straight; area between CuPb and AA1 narrow; AA1 strong and simple, some cross-vein between AA1 and AA2 have cross-veins between them; AA2 with six branches; cross-veins occasionally reticulated; no colouration pattern visible.

Locality and horizon

Xiaheyan Village, Zhongwei City, Yanghugou Formation (Ningxia Hui Autonomous Region, China); latest Bashkirian (latest Duckmantian) to middle Moscovian (Bolsovian), early Pennsylvanian ( Trümper et al., 2020).

Discussion

The new specimen can be confidently assigned to Archaeorthoptera as it exhibits the character “CuA (diverging from M + CuA) fused with the anterior branch of CuP (CuPa)”, which is the defining character state of this taxon ( BØthoux, 2007). Conversely, assignment to the Panorthoptera (including crown Orthoptera and stem groups closely related to them) can be excluded, as CuPa is not branched before its fusion with CuA. Non-panorthopteran Archaeorthoptera include “lobeattid” insects, the order Cnemidolestodea Handlirsch, 1937 (which is probably derived from a subset of lobeattid insects) and a number of unplaced species. The new specimen displays an RA–RP area narrow for a long distance, a trait occurring in the former, represented at Xiaheyan by Sinopteron huangheense Prokop and Ren, 2007 , Chenxiella liuae Liu, Ren and Prokop, 2009 , L. loculata , M. maimai and Pr. yangi . Among lobeattids, the new specimen shares with Miamia spp. (here considered to include Aviologus duquesnei Coty, HAEva, Prokop, Roques and Nel, 2014 ; and see BØthoux, 2008; BØthoux et al., 2012b; BØthoux and Jarzembowski, 2010) a comparatively broad ScP– R /RA area. Another peculiar trait shared with the corresponding species (but not unique to Miamia spp. ) is the very early branching of CuA + CuPa. However, the new specimen lacks the defining character state of Miamia , namely “in forewings, CuPa fuses with M + CuA” (BØthoux, 2008), a condition implying that CuA does not possess a free portion between its divergence from M + CuA and its fusion with CuPa. This free portion of CuA is present in the new specimen, which represents a plesiomorphy within Archaeorthoptera. In summary, the new specimen belongs to a species closely related to Miamia , yet it can be confidently excluded from this genus. It follows that it belongs to a new species to be accommodated in its own genus. Phtanomiamia gui is smaller than any known species of Miamia , and among the smallest “lobeattid” species.