Parahagla sibirica Sharov, 1968 (Insecta: Prophalangopsidae) from the Lower Cretaceous of the Democratic People's Republic of Korea and its biostratigraphical significance

 2022.11.3.

Chairman Kim Jong Il said:

"By developing our science and technology to world standards as soon as possible, the intellectuals should make a great contribution to increasing production rapidly and developing the economy."

Parahagla sibirica Sharov (1968), which belongs to the family Prophalangopsidae, has been reported from the Lower Cretaceous of Transbaikalia (Russia) and western Liaoning, northern Hebei and Gansu (China).

But no prophalangopsid orthoptera has been reported (Pak and Kim, 1996).

Recently, we recovered a well-preserved specimen assigned to Parahagla sibirica Sharov (1968) from the third member of the Sinuiju Formation at Ryonsang-dong.

Systematic paleontology

Order Orthoptera Olivier, 1789

Suborder Ensifera Chopard, 1920

Family Prophalangopsidae Kirby, 1906

Subfamily Chifengiinae Hong, 1982

Genus Parahagla Sharov, 1968.

Type species: Parahagla sibirica Sharov, 1968.

Included species: Only the type species.

Parahagla sibirica Sharov, 1968

Parahagla sibirica Sharov (1968) from the third member of the Sinuiju Formation
Fig. 1 Parahagla sibirica Sharov (1968) from the third member of the Sinuiju Formation (CKGP 20200728-C-1, 20200728-C-2)

Material: CKGP 20200728-C-1 (part), 20200728-C-2 (counterpart)

Wing incomplete, male (?); The specimen is deposited in the Laboratory of Paleontology, Faculty of Resource Science, Kim Il Sung University.

Locality and horizon: Ryonsang-dong, Sinuiju City, North Phyongan Province, Democratic People's Republic of Korea (DPRK); the third member, the Sinuiju Formation, Barremian-Aptian, Lower Cretaceous.

Description. Forewing long and narrow, length 37mm; area between ScA and anterior margin broad and of subtriangular shape, with several veinlets (sometimes branched), and several crossveins; ScA slightly sigmoidal, extending to anterior margin at basal 1/3.5 of forewing length, subparallel to branches of ScP; ScP also slightly sigmoidal and long, ending on anterior margin at about basal 2/3 of forewing length, with 10 oblique branches, crossveins between branches of ScP curved and irregularly spaced; R straight anteriorly; area between ScP and R narrow; RA and RP diverging at about basal 1/3 of forewing length, RA anteriorly pectinated with 4 simple branches; RP posteriorly pectinated with 6 branches; area between RA and RP broadened medially; M+CuA separate into M and CuA at about basal 1/3.5 of forewing length; M forking into MA and MP 2 mm basal of bifurcation of R into RA and RP; both MA and MP very long, simple, area between MA and MP distinct narrower in basal part and about three times broader in middle part; Stem CuA straight, connected to CuPaα slightly basal of fork MA+MP; free M extremely long, about three times as the length of free CuA; CuA + CuPaα forked opposite connection of CuA with CuPaα, with anterior branch pectinated with 3 secondary branches, and posterior branch simple; Pigmentation present on most of the forewing.

Discussion. P. sibirica was firstly erected by Sharov in 1968 based on both female and male forewings from the Lower Cretaceous Zaza Formation of Baissa, Siberia, Russia, and then discovered in the Jianshangou Bed, the lowermost fossil-bearing bed of the Yixian Formation in Liaoning and Hebei provinces, China dated at 124-123 Ma. After that P. sibirica Sharov (1968) was found in the Chijinbao Formation, the Jiuquan Basin, northwestern China.

Therefore we infer that it migrated to Sinuiju during the Aptian, so the age of the third member of the Sinuiju Formation is not Barremian, but younger than that of the Jianshangou bed of the Yixian Formation in northern Hebei and western Liaoning, China.

Our result published in the journal "Cretaceous Research" (2021) under the title of "Parahagla sibirica Sharov, 1968 (Insecta: Prophalangopsiae) from the Early Cretaceous of the Democratic People's Republic of Korea and its biostratigraphical significance" (https://doi.org/10.1016/j.cretres.2021.11.009) .