Cretapristocera longiscapa, Jouault & Ngô-Muller & Pouillon & Nel, 2021

Jouault, Corentin, Ngô-Muller, Valérie, Pouillon, Jean-Marc & Nel, André, 2021, New Burmese amber fossils clarify the evolution of bethylid wasps (Hymenoptera: Chrysidoidea), Zoological Journal of the Linnean Society 191 (4), pp. 1044-1058 : 1047-1048

CRETAPRISTOCERA LONGISCAPA SP. NOV.

( FIGS 2–4 )

u r n: l s i d: z o o b a n k. o r g: a c t: 2 1 A 7 C A E C - 4 2 5 0 45A9-A3B3-28F099EAEC25.

Holotype: Female, accession number IGR.BU-009, nearly complete and well-preserved female specimen in a rectangular piece of amber measuring 9 × 7 × 2.5 mm, together with a small Hymenoptera : Chalcidoidea; housed in the amber collection of the Geological Department and Museum (IGR) of the University of Rennes, France.

Type locality and horizon: Noije Bum Hill, Hukawng Valley, Kachin State, Myanmar; Lower Cenomanian, Upper Cretaceous.

Etymology: The specific epithet is derived from Latin longus, long, and scapus, shaft, for the elongated scape of this species.

Description: Female; body 2.1 mm long (as preserved), not depressed, almost smooth and not strongly foveolate; LFW 1.5 mm; castaneous; wings setose. LH 0.43 mm; WH 0.5 mm; WF 0.26 mm; HE 0.11 mm; OOL 0.25 mm; WOT 0.16 mm; DAO 0.04 mm; VOL 0.1 mm. Head not pubescent, with small, dorsal, median depression, finely punctuated but not sculptured; mandible with one strong and sharp tooth, projecting forward; six maxillary palpomeres, three (?) visible labial palpomeres; clypeus spined; antenna with ten flagellomeres with cylindrical crosssection; scape 0.37 × 0.07 mm, pedicel 0.13 × 0.04 mm (all measurements refer to length × width), F1 0.07 × 0.05 mm, F2 0.05 × 0.05 mm, F3 0.05 × 0.06 mm, F 4 0.06 × 0.07 mm, F5 0.06 × 0.08 mm, F 6 0.08 × 0.08 mm, F7 0.08 × 0.08 mm, F8 0.08 × 0.07 mm, F9 0.09 × 0.06 mm, F10 0.17 × 0.06 mm; occipital carina strongly marked; compound eye without microsetae; ocellar triangle not equilateral, with two posterior ocelli more distant from each other than from anterior. Mesosoma with dorsum smooth, not roughly sculptured; femora strongly thickened, tibia thin, tarsal claws simple; tibial spur formula 1-2-2; notauli well marked, posteriorly convergent; parapsidal furrows weak; metanotum developed medially and overlapping mesoscutellum posteriorly; metapectal–propodeal complex rectangular, not foveolate, with marginal carinae and no posterior spines; posterior margin of propodeum straight. Forewing covered with microsetae and bordered with small setae; anterior border not angularly incurved anterior to pterostigma; costal vein present; only veins C, Sc + R, Rs + M, 2r-rs&Rs, M + Cu, Cu and cells C (hardly visible), R and 2R1 present; vein cu-a absent and cell Cu opened; cell 2R1 distally opened; no basal stub of Rs + M; pterostigma long and narrow; poststigmal abscissa of R1 short, spectral veins not visible. Hindwing with only veins C and Sc + R and with three hamuli. Metasoma with short petiole; six tergites present (including three preserved detached from the body), T2 enlarged, convex, partly covering sternites; sting not preserved; length of clearly visible tergites: T1 0.23 mm, T2 0.29 mm, T3 at least 0.19 mm.

Remarks: It seems that the internal musculature of the fossil was preserved during the fossilization process, especially those of the legs ( Figs 2–3 ). It could be interesting to compare the evolution of the musculature and the insertion of the muscles between the Cretaceous and extant Bethylidae in a future study, using 3D X-ray tomography.

Figures

Figure 2. Cretapristocera longiscapa, sp. nov. holotype IGR.BU-009. A, habitus, in dorsal view. B, habitus, in ventral view. Scale bars: 0.5 mm.

Figure 3. Cretapristocera longiscapa, sp. nov. holotype IGR.BU-009. A, detailed ventral head view. B, detailed dorsal mesosomal view. C, wings. D, detailed view of leg preserved muscles. Scale bars: 0.5 mm.

Figure 4. Cretapristocera longiscapa, sp. nov.holotype IGR.BU-009. Line drawing of habitus, in dorsal view. Scale bar: 0.5 mm.