Parasyntexis Kopylov, 2019

Kopylov, Dmitry S., 2019, New anaxyelids (Hymenoptera: Anaxyelidae) from the Cretaceous of Asia, Zootaxa 4603 (2), pp. 341-353 : 346

Genus Parasyntexis Kopylov , gen. nov.

Etymology. From Greek para—close and generic name Syntexis Benson, 1935 . Gender masculine.

Type species. P. khasurtensis sp. nov.

Species included. Type species only.

Distribution. Lower Cretaceous of Transbaikalia, and, probably, North China (see below).

Diagnosis. Fore wing with costal area wide; pterostigma short and narrow; 1-R1 longer than pterostigma; both 1r-rs and 2r-rs developed, 1r-rs longer than 2r-rs; cell 2r wider than pterostigma; cell 3r significantly longer than pterostigma; Rs+M furcating after 1m-cu, 2Rs+M present, cell 1mcu pentagonal. Hind wing with cell r closed, Rs completely tubular; free endings of M, Cu, A developed; m-cu present. Ovipositor protruding beyond abdominal apex significantly.

Comparison. Parasyntexis differs from other genera in having narrow pterostigma and long 1-R 1 in fore wing and large body size. By the presence of 1r-rs, shape of cells 2r, 3r, 1mcu in fore wing, long ovipositor the new genus is the closest to recent genus Syntexis , but differs from it significantly in hind wing venation: presence of m-cu, tubular Rs and well developed free endings of M, Cu and A.

Remarks. A few specimens of Anaxyelidae belonging, obviously, to this genus, were noticed in Yixian collections of Nanjing Institute of Geology and Paleontology (NIGP): NNDL-0001, NNDL-0030, NNY-0095. The very similar specimen was also found in Baissa (PIN 4210/1834, Fig. 3B ), but the wings of that specimen are damaged badly and specific description is not possible.

By the fore wing venation Parasyntexis is closer to recent genus Syntexis than to previously known Cretaceous genera Eosyntexis and Cretosyntexis . However the presence of a sawfly with that type of venation in Cretaceous doesn’t seems surprisingly. Fore wing venation of Eosyntexis and Cretosyntexis looks apomorphic relatively to Syntexis . So the Syntexis type venation was expected in Mesozoic. Moreover, two new genera of Syntexinae described below have 1r-rs developed as well.

Unfortunately, there is almost no data on hind wing venation for Mesozoic syntexines Eosyntexis and Cretosyntexis . The only Cretaceous species with hind wing preserved was E. senilis Rasnitsyn, 1990 . Anyway, its hind wing was badly distorted. It was possible to conclude that hind wing venation of E. senilis is more complete comparatively to Syntexis , but the details of venation was lost ( Rasnitsyn 1990; Ortega-Blanco et al. 2008). P. khasurtensis is the first Cretaceous syntexine with well-preserved hind wing. The hind wing of Parasyntexis is much more plesiomorphic than hind wing of Syntexis : cell r is closed, Rs is completely tubular, free endings of M, Cu and A developed, m-cu present. The not described Yixian specimens mentioned above have the similar hind wing venation.

Figures

FIGURE 3. A—Brachysyntexis? sp., specimen PIN 3064/1939, Baissa, Russia, Lower Cretaceous; B—Parasyntexis sp., specimen PIN 4210/1843, Baissa, Russia, Lower Cretaceous; C—Dolichostigma tenuipes Rasnitsyn, 1968, specimen PIN 3064/1937, Baissa, Russia, Lower Cretaceous; D—Anaxyelidae subfam. indet., specimen PIN 923/728, Kempendyay, Russia, Lower Cretaceous or Upper Jurassic. Scale bars 5 mm.