Cretaxenomerus mirari Ulmer & Krogmann, 2023

UImer, Jonah M., Jansta, Petr, Azar, Dany & Krogmann, Lars, 2023, At the dawn of megadiversity - Protoitidae, a new family of Chalcidoidea (Hymenoptera) from Lower Cretaceous Lebanese amber, Journal of Hymenoptera Research 96, pp. 879-924 : 879

Cretaxenomerus mirari Ulmer & Krogmann sp. nov.

Fig. 12

Diagnosis.

Cretaxenomerus mirari differs from all other species in the genus by the following combination of characters: Head very transverse in dorsal view. Clypeus not as inflexed. Mesoscutum broader than long. Hind basitarsus with dense comb-like setation (Fig. 12D ). Syntergum straight, and longer than ¾ the length of the ovipositor (Fig. 12D ). Fore wing with a pronounced costal cell which is broader than the marginal vein, and cubital vein equal in length to distal tip of postmarginal vein (Fig. 12C ).

Description.

Female. Body length 1212. Coloration dark brown to black, slight metallic coloration on abdomen may be an artifact. Scape, legs and ovipositor sheaths dark brown, tip of ovipositor sheaths light brown. Wings lightly brownish infumated, wing venation brown. Head. Unusually long and low, about 1.5 × as wide as long and low, about 0.5 × as high as broad (Fig. 12A ). Eye broadly ovoid, but horizontally oriented (longer than height). Temple about ¼ as long as eye. Clypeus not deeply inflected. Epistomal sulcus and malar sulcus present. Toruli closer to inner eye margin than to each other. Antenna. Length 699, approximately 0.6 × as long as body. Scape 2.85 × as long as broad. All flagellomeres longer than wide, fu1-3 3.0 × as long as wide, fu4-10 about 2.0 × as long as wide (Fig. 12B ). Clava 2-segmented, length 88 (Fig. 12B ). MPS present on all segments, slightly askew, not extending beyond apical edge of segment. Micropilosity laterally on cl1-2 and fu9-10. Mesosoma. Length 342. Mesonotum wider than long and 0.6 × length of mesosoma. Prepectus narrow, dorsally hidden from dorsoposterior edge of lateral panel of pronotum. Axillae advanced. Mesopleuron obscured due to angle of specimen. Mesoscutellum short, 0.2 × as long as mesonotum (Fig. 12A :msct). Dorsellum narrow and band-like, ¾ length of mesoscutellum. Propodeum sloped, roughly 2 × as long as mesonotum (Fig. 12A :prp). Wings. Base of the fore wing including speculum with sparser pilosity than disc. Fore wing length 1046, 2.7 × as long as wide. Longest marginal seta of fore wing 39. Costal cell about 2 × as long as marginal vein and postmarginal vein (Fig. 12C ). Cubital vein very long, approximately ⅓ length of fore wing, strongly pigmented. Basal vein length 44, strongly pigmented. Submarginal vein length 367, costal cell of fore wing well developed. Marginal vein slightly longer than ¼ length of submarginal vein; strongly pigmented and broad, width 23. Stigmal vein short, length 33. Uncus with 4 uncal sensillae (Fig. 12C ). Postmarginal vein tapering towards wing margin, ⅔ length of marginal vein. Hind wing ⅗ length of fore wing, 6.7 × longer than wide. Longest marginal seta of hind wing 34. Venation and hamuli of hind wing not further than ½ length of wing (Fig. 12C ). Legs. Basitarsal comb present on fore leg. Basitarsomere equal in length to tarsomere 2-4 on fore leg. Dense setation along hind basitarsus (Fig. 12D ). Metasoma length 563, ≈1.6 × as long as mesosoma. Constricted petiole. Mt2-7 countable. Hypopygium elongate, reaching nearly to end of metasoma. Elongate, medial, longitudinal setal row down ventrum of metasoma. Syntergum about 0.5 × as long as metasoma and reaching up to about ¾ of ovipositor sheath length, broadened after insertion of cerci, spatulate (Fig. 12D ). Ovipositor ejected, about equal in length to metasoma; ovipositor tip with 3 teeth; ovipositor sheaths equal in length to ovipositor, stalk-like basally before widening distally and becoming spatulate with marginal setation (Fig. 12D ).

Male. Unknown.

Material examined.

Holotype: female, Hammana / Mdeyrij , Caza Baabda , Mouhafazet Mount Lebanon; lower Barremian. In amber mounted in Canada Balsam. Deposited at Natural History Museum of the Lebanese University, accession/specimen number: 157G.

Type condition.

Specimen complete, but terminal segments of the right antenna fragmented, and tarsal segments of the left fore leg longitudinally split; partial detachment from the amber along the right side of thorax and eye margin. Streaks in the amber make it difficult to clearly assess some characters.

Etymology.

The specific epithet is derived from the Latin ‘mirari’, which is the origin of the English ‘mirage’ in regards to the haziness of the specimen within the amber from the taphonomic process.

Notes.

Cretaxenomerus mirari shares several characters with P. curvus , namely the presence of 3 claval segments and a syntergal protrusion which is roughly ¾ of length of the ovipositor. While it is possible that P. mirari has an articulating syntergum which is simply not observable due to taphonomic processes, a postmarginal vein that is longer than the stigmal vein and a clear costal cell, would suggest that P. mirari is a distinct species for the sake of identification and until more specimens are discovered which may contradict its current placement.

Figures

Figure 12. Cretaxenomerus mirari, holotype A dorsal habitus with magnified view of clava B antenna, lateral C fore wing D ovipositor complex and terminal metasomal segments. Scale bars: 500 µm (A); 200 µm (C, D).