Burmotachinymphes pengi Chen, Deng et Yang, 2022

Chen, Xinrui, Chen, Peichao, Deng, Xinru, Yang, Qiang, Shi, Chaofan & Ren, Dong, 2022, A new mesochrysopid (Insecta: Neuroptera) from Upper Cretaceous, Zootaxa 5134 (4), pp. 597-600 : 598-599

Burmotachinymphes pengi Chen, Deng et Yang sp. nov.

( Fig. 1 )

urn:lsid:zoobank.org:act:BD3B288A-383D-4A64-8AA7-7F4D6B657480

Material. Holotype CNU-NEU-MA2018075, preserved nearly complete left wings (wing base not preserved).

Type locality and horizon. Hukawng Valley of the northern state of Kachin in Myanmar (26°200’N, 96°360’E); lowermost Cenomanian, Upper Cretaceous .

Etymology. The specific name is after Mr Wei Peng (Jilin, China), who is very interested in Entomology and donated the specimen for this study.

Diagnosis. Forewing RP with thirteen branches, MP with six distal pectinate branches, CuA with five distal pectinate branches. Hind wing RP with ten branches, MP with five distal pectinate branches, CuA with about seven distal pectinate branches. Conspicuous pterostigma present in hind wing (not preserved in forewing). Pterostigmal area with eight veinlets.

Description. Forewing: Length about 18.3 mm (complete length estimated more than 20 mm), width about 6.6 mm as preserved. Forewing relatively broad, with rounded apex. Trichosors absent. Costal space straight, with simple unforked veinlets, equally narrow. Pterostigma not preserved. Endings of ScP and RA indistinct. Subcostal space broad, no crossvein detected. The space between RA and RP broad in proximal part, narrowed towards wing apex. Thirteen crossveins detected between RA and RP. Stem of RP smooth and zigzagged, with thirteen regularly zigzagged branches. Numerous crossveins present in radial space, venation reticulated, gradate series inconspicuous, inner gradate series better defined than outer gradate series. Crossvein present between MA and RP before the origin of RP1, connecting stem of RP and intramedian cell. Basal part of M and its dividing into MA and MP not preserved. MA simple. MP with six pectinate terminal branches. CuA with five pectinate terminal branches. RP, MA, MP and CuA not coalesced. CuP poorly preserved. A not preserved.

Hind wing: Length about 16.3 mm, width about 5.2 mm as preserved. Trichosors absent. Costal space similar with forewing. Pterostigma conspicuous. Pterostigma area with eight veinlets. ScP fused with RA apically, then end on costal margin near wing apex. Subcostal space relatively narrow, crossveins not detected. The space between RA and RP broad in proximal part, narrowed towards wing apex, with eleven crossveins. Stem of RP smooth and zigzagged, with ten regularly, zigzagged branches. Numerous crossveins in radial space present, venation reticulated, gradate series inconspicuous, inner gradate series better defined than outer gradate series. Crossvein present between MA and RP before the origin of RP1, connecting stem of RP and base of second intramedian cell. M divided into MA and MP before the origin of RP1. MA simple. MP with five pectinate terminal branches. CuA with about seven pectinate terminal branches. RP, MA, MP and CuA not coalesced. A not preserved.

Remarks. The new species is assigned to Burmotachinymphes based on pterostigma obvious; costal crossveins simple; RP diverged from RA at an angle of>30°; RP with zigzagged stem; crossveins in RP area forming gradate series; MA simple, MP with pectinate branches. It is easy to distinguish from Burmotachinymphes bilobata by body size. The preserved part of forewing of Burmotachinymphes pengi sp. nov. is more than 18 mm in length, and the estimated complete length more than 20 mm. The hind wing is more 16 mm in length. In contrast, Burmotachinymphes bilobata has forewing long 12.7 mm by estimation, hind wing long 10.9 mm. In addition, there are some other distinct differences between them: Burmotachinymphes bilobata RP has seven branches with RP1 to RP3 each bearing two marginal branches and RP4 to RP7 simple in fore- and hind wings. MP has five distal marginal pectinate branches in forewing, and four in hind wing. CuA has four distal marginal pectinate branches in fore- and hind wings. The new species has thirteen RP branches with RP1 to RP8 each bearing at least two marginal branches and RP9 to RP13 simple in forewing. In hind wing, there are ten RP branches with RP1 to RP6 each bearing two marginal branches and RP7 to RP10 simple. MP has six distal marginal pectinate branches in forewing, and five distal marginal pectinate branches in hind wing. CuA has five distal marginal pectinate branches in forewing and about seven distal marginal pectinate branches in hind wing.

Tachinymphes is the largest genus in this subfamily with six species. Nanochrysopa Nel et al., 2005 is a monotypic genus. Burmotachinymphes shares characters with other genera of Tachinymphinae in the MP not touching CuA. Besides, Burmotachinymphes have several unique characters, i.e., 1) MA simple, 2) MP and CuA with pectinate distal marginal branches, and 3) RP, MA, MP and CuA not coalesced evidently.

Figures

FIGURE 1. Burmotachinymphes pengi Chen, Deng et Yang sp. nov., holotype CNU-NEU-MA2018075. A, Habitus in dorsal view; B, Venation of left forewing and hind wing. Scale bars = 2 mm.