Preservation and occurrence of parasitoids

Externally, nearly all Quercy fly pupae were preserved as isolated endocasts, of which many were still covered by the puparium, the hardened skin of the last larval instar (Fig. 1a, j, Supplementary Fig. 1). Sometimes body parts of adult flies (especially legs) were recognizable through a partly translucent surface (Supplementary Fig. 1ay, be, Supplementary Table 1). Apart from legs and isolated bristles, remains of host flies (Fig. 1j–o) were rarly preserved and did not provide diagnostic characters. In 55 pupae (3.8%) of Eophora we identified parasitation events, which were mostly represented by adult wasps. Preservation of the parasitoids ranged from barely recognizable to well-preserved specimens (Supplementary Figs. 2–5, Supplementary Table 1). In most cases, sclerites were preserved as voids inside the mineralized matrix (Fig. 1c, g–i). Nineteen wasps had folded wings and showed the symmetric posture of a late wasp pupa (Fig. 1e), while 20 specimens were evidently hatched, as indicated by unfolded wings and an asymmetric body posture (Fig. 1f, Supplementary Table 1).

Fig. 1 X-ray tomography of fossils. a Host fly puparium (NRM-PZ Ar65720). b Volume rendering of a. c Longitudinal section of b. d Parasitoid wasp inside host (perspective view; Supplementary Movie 1). e Xenomorphia resurrecta, male (NRM-PZ Ar65720) in symmetric posture with folded wings. f X. resurrecta, female (NMB F2875) in asymmetric posture with unfolded wings. g–i Transverse sections of tomogram as indicated in b. j Host fly puparium (NRM-PZ Ar65810). k Volume rendering of j. l Longitudinal section of k. m Volume rendering of host fly (perspective view). n–o Transverse sections of tomogram as indicated in k. Scale bars: a–c, e, f, j–l = 1 mm; g–i, n, o = 250 µm Full size image

Systematic palaeontology

In order to assess the size variation within the species, we measured the length between the anterior margin of the propleurae and the anterior tip of the median keel of the propodeum. The reference lengths for holo- and paratypes are listed in Supplementary Table 1 along with information on the preservation of hosts and parasitoid wasps. All other measurements refer to holotypes only and are included in the species descriptions. Differences in size and preservation are further documented by surface renderings of 30 parasitoid heads covering all species (Supplementary Fig. 5).

Family Diapriidae Haliday, 1833 Subfamily Diapriinae Haliday, 1833 Tribe Spilomicrini Ashmead, 1893 Xenomorphia Krogmann, van de Kamp & Schwermann gen. nov.

Type species. Xenomorphia resurrecta Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The genus name refers to the endoparasitoid Xenomorph creature featured in the “Alien” media franchise.

Diagnosis. Antenna 14-segmented in both sexes, apical flagellomeres bead-like. Epistomal sulcus distinct and straight. Mandibles narrow, 2-toothed. Labrum exposed.

Xenomorphia resurrecta Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The specific epithet points out the “resurrection” of the extinct species by means of digital imaging.

Diagnosis. Malar sulcus distinct. Petiole cylindrical, 1.6–1.8 times as long as wide.

Referred material. Holotype ♀: NMB F2875. Paratypes ♀♀: NMB F2615, NMB F2822, NMB F2840, NMB F2856, NMB F2972, NMB F2982, NMB F3018, NMB F3103, NMB F3220, NMB F3389, NMB F3394, NMB F3477, NMB F3612, NRM-PZ Ar65771, NRM-PZ Ar65793, NRM-PZ Ar65913, and NRM-PZ Ar65938. Paratypes ♂♂: NMB F2557, NMB F2674, NMB F2732, NMB F2752, NMB F2831, NMB F2851, NMB F2854, NMB F2945, NMB F2985, NMB F3140, NMB F3146, NMB F3254, NMB F3278, NMB F3516, NMB F3562, NMB F3610, NRM-PZ Ar65720, NRM-PZ Ar65767, NRM-PZ Ar65772, NRM-PZ Ar65794, NRM-PZ Ar65800, NRM-PZ Ar65823, NRM-PZ Ar65895, and NRM-PZ Ar65948 (Figs. 1d–f, 2, 3, 4, Supplementary Fig. 2, Supplementary Fig. 3, Supplementary Fig. 5a–x, Supplementary Data 1 and 2, Supplementary Movies 1 and 2).

Fig. 2 Visualization and frequency of the four parasitoid species. A total number of 55 parasitation events were recognized. Xenomorphia resurrecta dominated with 18 females and 24 males. Xenomorphia handschini was represented by one female, three males, and one pupa of undetermined sex (not displayed), Coptera anka by three females and one male and Palaeortona quercyensis by a single female. Additionally, a single unidentified putative second instar larva and a set of last larval instar mandibles presumably left behind by an emerged parasitoid were identified. Scale bar: 1 mm Full size image

Fig. 3 Illustration of a female Xenomorphia resurrecta ovipositing into a puparium. The picture is directly based on tomography data of NMB F2875 (wasp; Figs. 1f, 2, 4a–m, Supplementary Figs. 1e, 2e, and 5b) and NRM-PZ Ar65767 (puparium; Supplementary Fig. 1aj). Colors and parts of pilosity are imaginary. Supplementary Movie 2 shows how the illustration was derived from original tomography data Full size image

Fig. 4 Digital reconstruction of Xenomorphia resurrecta gen. & sp. nov. (Diapriidae: Diapriinae: Spilomicrini). Female holotype NMB F2875 (a–m) and male paratype NRM-PZ Ar65720 (n–v). Habitus (a–d), head (e), left antenna (f), left foreleg (g), right midleg (h), right hind leg (i). Internal anatomical structures (j–m): mesonotum ventral view (j), propectus dorsolateral view (k), mesopectus anterior view (l), metapectal-propodeal complex anterior view (m). Habitus (n–q), head (r), left antenna (s), right foreleg (t), right midleg (u), right hind leg (v). Scale bar: a–i, n–v = 1 mm; j = 500 µm; k = 250 µm; l, m = 400 µm Full size image

Locality. The fossils originate from the phosphorite mines of the Paleogene fissure fillings of the Quercy region in South-Central France. The specimens were discovered near Bach18 (coordinates: 44°21′ N, 1°40′ E). More information on the exact locality, collection date and collector are unknown.

Description. Female (Figs. 1f, 3, 4a–m). Reference length: 824 µm. Head sculpture mainly smooth, frons with scattered setiferous punctures. Head height: 529 µm, head width: 533 µm, and head length: 435 µm. Ocelli large, ratio between interocellar distance and ocelloocular distance (IOD:OOD) = 0.58. Eyes large, 277 µm high and 215 µm wide. Malar space 91 µm, malar sulcus present. Occipital carina complete, horseshoe-shaped, anteriorly marked by small ridges. Clypeus narrow, laterally with enlarged anterior tentorial pits, dorsally marked by distinct and straight epistomal sulcus. Mandibles narrow, two-toothed, leaving large, semicircular area from ventral clypeal margin. Area covered by membranous labrum. Toruli oriented dorsally, positioned on distinct antennal shelf, about half-way upon face. Antennal shelf with transverse wrinkles. Antennal shelf connected to epistomal sulcus by two submedian frontal sulci. Supraclypeal area between sulci slightly expanded. Antenna: 14-segmented, elbowed with elongate scape. Scape reaching mid-height of lateral ocellus. Apical flagellomeres bead-like, with few scattered setae. First flagellomere cylindrical, distinctly longer than subsequent flagellomeres. Subsequent flagellomeres short, hardly longer than wide. Multiple setal bases present as pores on individual antennomeres. Pronotum with distinct neck, dorsal pronotal surface short, and pronotum adjacent to mesoscutum. Posterior pronotal margin with elongate setae. Lateral panel of pronotum large and triangular, adjacent to mesopleuron. Pronotal depression for accommodation of profemur absent. Pronotal neck with irregular sculpture, dorsal and lateral pronotal margin with indistinct foveae, rest of pronotum smooth. Hind corner of pronotum reaching tegula. Mesothoracic spiracles positioned at lateral margin of pronotum, posteriorly enclosed by prepectal shelf, dorsally reaching tegula. Mesothoracic spiracles nearly completely enclosed by cuticle, omitting just small membranous stripe dorsally. Prosternum subrectangular, transversely divided by complete cross carina. Three large profurcal pits present, one median in anterior half and two submedian in posterior half of prosternum. Profurca u-shaped, profurcal arms completely fused with prosternum. Position of articulation point between propleuron and profurcal arm at posterior end of propectus. Propleural arms anteriorly pointed.

Mesoscutum smooth, with few scattered elongate setae. Mesoscutal suprahumeral sulcus weakly developed. Notauli present as broad, curved sulci, which are slightly dilated posteriorly. Notauli anteriorly nearly reaching anterior mesoscutal margin and posteriorly nearly reaching transscutal articulation. Notauli internally preserved as rather sharp ridges. Transscutal articulation straight and complete. scutoscutellar sulcus marked by two large, ovoid pits, which are medially separated by straight ridge. Pits internally not well marked. Axillae narrow and smooth. Axillulae with two rows of short setae. Mesoscutellar disc laterally separated from axillula by short ridges. Hind margin of mesoscutellum distinctly foveolate. Mesopleuron smooth and glabrous, mesofemoral depression indistinct. Mesopleuron laterally divided by diagonal sulcus. Mesepisternum anteriorly with distinct procoxal depressions, which are medially separated by distinct carina. Acetabular and mesotrochantinal carina present, meeting medially on ventral mesopleuron. Mesodiscrimen complete and foveolate. Anterior mesofurcal pit inconspicuous, marked by anteriormost fovea of foveolate mesodiscrimen. Posterior mesofurcal pit present between mesocoxal foramina. Mesocoxal foramina not completely enclosed by cuticle. Mesodiscrimenal lamella not reaching anterior margin of mesopectus. Anterior mesofurcal base situated about mid-way through median mesopectal length. Mesofurcal bridge medially interrupted, situated only slightly above mid-height of mesofurca.

Metascutellum with two raised lateral and one raised median carina, and one less distinct transverse carina, metascutellum posteriorly expanded. Lateral panel of metanotum composed of anteriorly reduced foveae. Metapleuron subrectangular, coarsely reticulate. Metepisternum with distinct depressions for accommodating mesocoxae but without transverse or median carina. Single metafurcal pit present anteromedially of metacoxal foramina. Metafurca indistinct, u-shaped, basally fused to highly raised paracoxal ridge. Metadiscrimenal lamella reaching mid-level of metacoxal foramina.

Propodeum with coarse irregular sculpture, medially with anteriorly projecting keel. Plicae and median carina present. Hind margin of propodeum carinate. Petiole cylindrical, laterally with short pilosity, 1.64 times as long as wide. Petiole dorsally with multiple irregular longitudinal carinae, ventrally with fewer longitudinal carinae. Second metasomal tergum enlarged, anterior margin medially divided, overlapping petiole. Subsequent terga short. Second and third metasomal sternum enlarged, subsequent sterna short.

Wings: Forewing unfolded, venation not traceable, and outer wing margin with long pilosity.

Legs: Foreleg with elongate simple trochanter, protibial spur with distinct cleft. Midleg with elongate simple trochanter and two mesotibial spurs. Hind leg with two-segmented trochanter and two metatibial spurs.

Male (Figs. 1e, 4n–v). Measurements given for paratype: NRM-PZ Ar65720. Very similar to female but differs in following features. Reference length: 911 µm. Head height: 605 µm, head width: 599 µm, and head length: 481 µm. IOD:OOD: 0.70. Antenna: 14-segmented, but distinctly longer than in female. Scape, pedicel, and first flagellomere comparable to female, but subsequent flagellomeres cylindrical, i.e., distinctly longer than broad. Eyes 328 µm high and 260 µm wide. Malar space 82 µm. Petiole very similar in proportions (1.75 times as long as wide) and shape, but with more extensive pilosity, also extending to ventral surface. All legs with two-segmented trochanters.

Xenomorphia handschini Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The species epithet honors Swiss entomologist Eduard Handschin (1894–1962), who found the first traces of a parasitoid wasp in the Quercy fossils and recognized the scientific importance of these deposits.

Diagnosis. Malar sulcus distinct only in males, faintly indicated in females. Petiole distinctly broadened, subquadrate, 1.03–1.20 times as long as wide.

Referred material. Holotype ♀: NMB F3042. Paratypes ♂♂: NMB F2543, NMB F3192, NMB F3571, and NRM-PZ Ar65942. Pupa: NRM-PZ Ar65822 (Figs. 2, 5, Supplementary Fig. 4a–f, Supplementary Fig. 5y–aa, Supplementary Data 3, 4).

Fig. 5 Digital reconstruction of Xenomorphia handschini gen. & sp. nov. (Diapriidae: Diapriinae: Spilomicrini). Female holotype NMB F3042 (a–m) and male paratype NMB F2543 (n–v). Habitus (a–d), head (e), left antenna (f), right foreleg (g), right midleg (h), left hind leg (i). Internal anatomical structures (j–m): mesonotum ventral view (j), propectus dorsolateral view (k), mesopectus anterior view (l), metapectal-propodeal complex anterior view (m). Habitus (n–q), head (r), right antenna (s), right foreleg (t), right midleg (u), right hind leg (v). Scale bar: a–i, n–v = 1 mm; j = 500 µm; k = 250 µm; l, m = 400 µm Full size image

Locality. As for X. resurrecta.

Description. Female (Fig. 5a–m). Reference length: 734 µm. Head sculpture mainly smooth, frons with scattered punctures. Setae not preserved. Head height: 467 µm, head width: 483 µm, head length: 396 µm. Ocelli large. Eyes large, 242 µm high and 209 µm wide. Malar space 66 µm, malar sulcus absent. Occipital carina complete, horseshoe-shaped, anteriorly marked by small ridges. Clypeus narrow, laterally with enlarged anterior tentorial pits, dorsally marked by distinct and straight epistomal sulcus. Mandibles covered by numerous scattered punctures. Mandibles narrow, two-toothed, leaving large, semicircular area from ventral clypeal margin. Area covered by membranous labrum. Toruli dorsally oriented, positioned on indistinct antennal shelf, about half-way upon face. Antennal shelf with few indistinct oblique wrinkles. Antennal shelf connected to epistomal sulcus by two submedian frontal sulci. Supraclypeal area between sulci slightly expanded. Antenna: 14-segmented, elbowed with elongate scape. Scape reaching mid-height of lateral ocellus. Apical flagellomeres bead-like, with few scattered setae. First flagellomere longer than subsequent flagellomeres. Subsequent flagellomeres distinctly to slightly longer than wide. Multiple setal bases present as pores on individual antennomeres. Pronotum with distinct neck, dorsal pronotal surface short, pronotum adjacent to mesoscutum. Posterior pronotal margin with elongate setae. Lateral panel of pronotum large and triangular, adjacent to mesopleuron. Pronotal depression for accommodation of profemur absent. Pronotal neck with irregular sculpture, dorsal and lateral pronotal margin with indistinct foveae, rest of pronotum smooth. Hind corner of pronotum reaching tegula. Mesothoracic spiracles positioned at lateral margin of pronotum, posteriorly enclosed by prepectal shelf, dorsally reaching tegula. Mesothoracic spiracles nearly completely enclosed by cuticle omitting just small membranous stripe dorsally. Prosternum subrectangular, transversely divided by complete cross carina. Three large profurcal pits present, one median in anterior half and two submedian in posterior half of prosternum. Profurca u-shaped. Only bases of profurcal arms preserved. Propleural arms incompletely preserved.

Mesoscutum smooth, with numerous scattered elongate setae. Notauli present as very broad, curved sulci, which are slightly dilated posteriorly. Notauli anteriorly nearly reaching anterior mesoscutal margin and posteriorly nearly reaching transscutal articulation. Notauli internally marked by broad ridges. Transscutal articulation straight and complete. Scutoscutellar sulcus marked by two large semicircular pits, which are medially separated by straight ridge. Pits internally well marked. Axillae narrow and smooth. Axillulae with scattered short setae. Mesoscutellar disc laterally separated from axillula by short ridges. Hind margin of mesoscutellum distinctly foveolate. Mesopleuron smooth and glabrous, mesofemoral depression indistinct. Mesopleuron laterally divided by diagonal sulcus. Mesepisternum anteriorly with distinct procoxal depressions, which are medially separated by distinct carina. Acetabular carina only weakly indicated, mesotrochantinal carina distinct, both carinae meeting medially on ventral mesopleuron. Mesodiscrimen complete and foveolate. Single mesofurcal pit present between mesocoxal foramina. Mesocoxal foramina not completely enclosed by cuticle. Mesofurca not preserved.

Metascutellum with two raised lateral and one raised median carina, and one less distinct transverse carina, metascutellum posteriorly expanded. Lateral panel of metanotum mainly smooth with traces of reduced foveae. Metapleuron subrectangular, coarsely reticulate. Metepisternum with indistinct depressions for accommodating mesocoxae, and without transverse or median carina. Single metafurcal pit present anteromedially of metacoxal foramina. Metafurca not preserved.

Propodeum with coarse irregular sculpture, medially with anteriorly projecting keel. Plicae and median carina present. Hind margin of propodeum carinate. Petiole distinctly broadened, subquadrate, 1.03 times as long as wide, laterally with short pilosity. Petiole dorsally with multiple irregular longitudinal carinae, ventrally mainly smooth, longitudinal carinae only posteriorly indicated. Second metasomal tergum enlarged, anterior margin medially divided, overlapping petiole. Subsequent terga short. Second and third metasomal sternum enlarged, subsequent sterna short.

Wings: Folded but hardly traceable.

Legs: All legs with two-segmented trochanters. Protibial spur with distinct cleft. Midleg with two mesotibial spurs. Hind leg with two metatibial spurs.

Male (Fig. 5n–v). Measurements given for paratype: NMB F2543. Very similar to female but differs in following features. Reference length: 911 µm. Head height: 596 µm, head width: 608 µm, head length: 478 µm. IOD:OOD: 0.74. Frons with scattered punctures and elongate setae. Antenna: 14-segmented, but distinctly longer than in female. Scape, pedicel and first flagellomere comparable to female, but subsequent flagellomeres cylindrical, i.e., distinctly longer than broad. Multiple setal bases present as pores on individual antennomeres and distinct setation preserved. Eyes 321 µm high and 243 µm wide. Malar space 93 µm, malar sulcus present. Mandibles smooth, without scattered punctures. Antennal shelf with few oblique wrinkles. Scutoscutellar sulcus marked by two large irregular pits, which are medially separated by two oblique ridges. Axillulae with distinct short setation. Acetabular carina distinctly indicated. Petiole 1.20 times as long as wide, laterally with scattered elongate seta and ventrally with dense short setation. Few complete longitudinal carinae present ventrally.

Comments: Both species of Xenomorphia share 14-segmented antennae in both sexes with the extant genera Xenismarus Ogloblin and Chilomicrus Masner and García. These genera are restricted to South America and considered early lineages of Diapriidae22. Xenomorphia can be readily distinguished from Chilomicrus in a number of morphological characters, including presence of an exposed labrum (absent in Chilomicrus), apical flagellomeres bead-like (subquadrate in Chilomicrus) and scutoscutellar sulcus marked by two large, ovoid pits, which are medially separated by a straight ridge (not clearly separated in Chilomicrus). Xenomorphia appears morphologically very similar to Xenismarus but differs in having the upper tooth of the mandible shorter than the lower tooth and in the presence of plicae. As most shared characters seemingly represent symplesiomorphies, we here refrain from placing the fossil species in the extant genus Xenismarus based on the available morphological evidence, but it may turn out to be closely related or even congeneric.

Tribe Psilini Hellén, 1963 Coptera Say, 1836

Diagnosis. Body predomimantly smooth. Labrum exposed, subtriangular. Mandible long, falcate, projecting posteriorly. Postgenal cushion present. For full diagnosis see Masner and García22.

Coptera anka Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The specific epithet is the Swedish word for duck and refers to the duck-like appearance of the head and the origin of the holotype from the Swedish Museum of Natural History.

Diagnosis. Head distinctly elongate anteriorly with toruli at anteriormost position. Ocelli large, ratio between IOD and OOD 1.11. Mandible three-toothed.

Referred material. Holotype ♀: NRM-PZ Ar65897. Paratypes ♀♀: NMB F2848, NMB F2954. Paratype ♂: NMB F3154 (Figs. 2 and 6, Supplementary Fig. 4g–j, Supplementary Fig. 5ab, ac, Supplementary Data 5 and 6).

Fig. 6 Digital reconstruction of Coptera anka sp. nov. (Diapriidae: Diapriinae: Psilini). Female holotype NRM-PZ Ar65897 (a–f, k, l), female paratype NMB F2848 (g–j, m, n) and male paratype NMB F3154 (o–w). Habitus (a–d), head (e), left antenna (f), left foreleg (g), left midleg (h), right hind leg (i). Internal anatomical structures (j–m): mesophragma ventral view (j), mesonotum ventral view (k), propectus dorsolateral view (l), mesopectus anterior view (m), metapectal-propodeal complex anterior view (n). Habitus (o–r), head (s), right antenna (t), right foreleg (u), left midleg (v), left hind leg (w). Scale bar: a–i, o–w = 1 mm; j, k = 500 µm; l = 250 µm; m, n = 400 µm Full size image

Locality. As for X. resurrecta.

Description. Female (Fig. 6a–n). Reference length: 717 µm. Body predominantly smooth. Head distinctly elongate anteriorly. Head with deep punctures on antennal shelf and on frons anterior to ocelli. Head height: 523 µm, head width: 456 µm, head length: 592 µm. Ocelli large, IOD:OOD = 1.11. Eyes large, 261 µm high and 210 µm wide. Malar space 67 µm, malar sulcus absent. Occipital carina complete, semicircular, anteriorly not marked by small ridges or punctures. Clypeus convex, about as high as wide, laterally with distinct anterior tentorial pits, dorsally hardly marked by faint epistomal sulcus. Mandibles extremely narrow and elongate, not clasped, 3-toothed, projecting diagonally backward. Labrum triangular. Oral carina distinctly developed, postgenal cushion developed. Toruli at anteriormost position of head, on distinctly protruding antennal shelf. Antennal shelf without any wrinkles. Frons armed with two lateral projections about mid-way between levels of anterior ocellus and toruli. Anteriormost area of frons marked by carinae connecting antennal shelf, lateral projections and anterior ocellus. Additional lateral carina leading from this area diagonally to lateral ocelli and above eyes. Antenna: 12-segmented, elbowed with elongate scape. Scape highly modified, with distinct lateral projection and two sharp corners protruding insertion to pedicel. First flagellomere cylindrical, distinctly longer than subsequent flagellomeres. Clava elongate, distinctly longer than wide. Second and third flagellomere still cylindrical, subsequent flagellomeres spherical. Multiple setal bases present as pores on individual antennomeres. Pronotum adjacent to mesoscutum. Pronotum with long and distinct neck, dorsal pronotal surface short, but visible in dorsal view. Distinct transverse pronotal sulcus present between pronotal neck and dorsal surface. Pronotal neck with irregular striae in posterior half. Posterior margin of pronotum with transverse row of punctures with elongate setae corresponding to distinct internal ridge that articulates with anterior margin of mesoscutum and laterally connects with postspiracular apodemes. Pronotum laterally to neck with distinct patches of short setae. Lateral panel of pronotum large and triangular, adjacent to mesopleuron. Pronotal depression for accommodation of pro-femur absent. Hind corner of pronotum reaching tegula. Mesothoracic spiracles positioned at lateral margin of pronotum, on spike-like protuberances, spiracles posteriorly enclosed by prepectal shelf, dorsally reaching tegula. Mesothoracic spiracles completely enclosed by cuticle. Propleura smooth, posterior margin with narrow rectangular fields. Fields anteriorly and laterally carinate, serving as articulation point for anterior surface of procoxae. Articulation of procoxae further enhanced by two rounded impressions on rectangular prosternum, by distinct procoxal impressions on ventral mesopleuron and by ventrally flattened expansions of pronotum laterally to procoxal foramina. Prosternum transversely divided by complete cross carina. A single median profurcal pit present in extremely narrowed dorsal part of prosternum. Profurca u-shaped, profurcal arms only preserved as thin structures. Propleural arms incompletely preserved.

Mesonotum dorsally flattened. Mesoscutum wider than long, smooth, with very few scattered elongate setae arising from punctures. Notauli present as very broad, curved sulci, which are distinctly dilated posteriorly and deeply pitted anteriorly. Notauli anteriorly nearly reaching anterior mesoscutal margin and posteriorly nearly reaching transscutal articulation. Notauli internally rather weakly marked. Preaxilla smooth, deeply concave with two carinae on surface, arising from anterior and antemedian mesonotal wing processes. Anterior carina articulating with anterior margin of tegula. Tegula huge and rounded, posteriorly reaching posterior wing process. Tegula laterally expanded, with smooth and flattened anterior surface. Tegula with few elongate setae. Transscutal articulation straight and complete. Mesoscutellum with few scattered setae. Scutoscutellar sulcus marked by two large, ovoid pits, which are medially separated by broad straight ridge. Pits internally well defined. Axillae large, triangular, and smooth. Mesoscutellar disc laterally separated from axillula by distinct straight ridges, which are marked by lateral depressions. Hind margin of mesoscutellum distinctly foveolate. Posterior wing process short and broadened, blunt with smooth surface. Mesopleuron smooth and glabrous, mesofemoral depression absent. Mesepimeron with two longi-tudinal ridges connecting anterior and posterior mesopectal margin and separating long rectangular area. Epicnemial pit present with reduced, short pilosity. Sternaulus developed as complete carina connecting epicnemial pit with posterior margin of mesopectus. Mesepisternum anteriorly with distinct procoxal depressions, which are medially separated by short and indistinct carina. Raised acetabular and mesotrochantinal carinae present. On each side posterior margin of acetabular carina connected by longitudinal carina to anterior margin of mesotrochantinal carina. Mesodiscrimen hardly traceable. Two distinct mesofurcal pits developed. Round anterior pit present at acetabular carina, slit-like posterior pit present medially on mesotrochantinal plate just anterior to mesocoxal foramina. Mesocoxal foramina not completely enclosed by cuticle. Mesodiscrimenal lamella reaching close to anterior margin of mesopectus. Mesofurca with two solid bases, mesofurcal bridge complete with dorsal orientation.

Metanotum anteriorly overlapped by mesoscutellum. meta-scutellum with two distinctly raised lateral and distinct median carina. Lateral panel of metanotum composed of foveae. Metapleuron subrectangular, mainly smooth, with ventral row of foveae. Metepisternum with distinct depressions for accommodating mesocoxae, and with distinct median carina (corresponding to metadiscrimen). Single metafurcal pit present anteromedially of metacoxal foramina, posterior to raised carina. Metacoxal foramina with lateral projections. Metafurca indistinct, u-shaped, completely fused to highly raised paracoxal ridge. Metadiscrimenal lamella reaching nearly to mid-level of metacoxal foramina.

Median keel on propodeum formed by v-shaped median carina pointing anteriorly. Anterior margin of propodeum deeply excavate and smooth. Dorsal surface of propodeum with two submedian carinae (instead of single median carina). Plicae developed, dorsal propodeal surface between plicae and submedian carinae smooth. Posterior margin of propodeum deeply excavate, posterolateral corners strongly projecting and broadly bifurcate. Hind margin of propodeum carinate.

Petiole cylindrical, laterally with long pilosity, 1.49 times as long as wide. Petiole with three dorsal, three lateral and two ventral carinae. Second tergum greatly enlarged, anterior margin with deep and narrow median incision. Second tergum overlapping petiole. Subsequent terga extremely shortened. Second sternum greatly enlarged, covering subsequent three sterna. Second sternum with deep grooves filled with micropilosity.

Wings: Not traceable. Legs: All legs with elongate simple trochanters. Protibial spur with distinct cleft. Midleg with two mesotibial spurs. Hind leg with two metatibial spurs.

Male (Fig. 6o–w). Measurements given for paratype: NMB F3154. Very similar to female but differs in following features. Reference length: 652 µm. Head height: 468 µm, head width: 389 µm, head length: 507 µm. IOD:OOD: 0.90. Antenna: 14-segmented. Eyes 224 µm high and 192 µm wide. Foveae on lateral panel of metanotum hardly visible. Petiole 1.83 times as long as wide. T2 hardly overlapping petiole.

Comments: The new species agrees with nearly all generic characters listed by Masner and García22 for Coptera Say, many of which can be regarded as synapomorphies. The only observed morphological difference is the presence of three mandibular teeth in C. anka (two in Coptera), which we find insufficient to diagnose a new genus.

Palaeortona Krogmann, van de Kamp & Schwermann gen. nov.

Type species. Palaeortona quercyensis Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The genus name refers to the morphologically similar extant genus Ortona Masner and García.

Diagnosis. Body without hairy cushions or foamy structures. Labrum exposed, semicircular. Mandible small, not protruding, bidentate. Head not depressed. Oral carina distinct.

Palaeortona quercyensis Krogmann, van de Kamp & Schwermann sp. nov.

Etymology. The species epithet refers to the type locality.

Diagnosis. Level of toruli lower than midpoint of eye. Pronotal neck distinctly developed. Median ocellus nearly adjacent to lateral ocelli. Petiole cylindrical, 1.3 times as long as wide.

Referred material. Holotype ♀: NMB F2770 (Figs. 2 and 7, Supplementary Fig. 4k, Supplementary Fig. 5ad, Supplementary Data 7).

Fig. 7 Digital reconstruction of Palaeortona quercyensis gen. & sp. nov. (Diapriidae: Diapriinae: Psilini). Female holotype NMB F2770. Habitus (a–d), head (e), right antenna (f), right foreleg (g), right midleg (h), and right hind leg (i). Internal anatomical structures (j–m): mesonotum ventral view (j), propectus dorsolateral view (k), mesopectus anterior view (l), and metapectal-propodeal complex anterior view (m). Scale bar: a–i = 1 mm; j = 500 µm; k = 250 µm; l, m = 400 µm Full size image

Locality. As for X. resurrecta.

Description. Female (Fig. 7). Reference length: 810 µm. Head sculpture mainly smooth, frons, face, genae and clypeus with scattered punctures. Elongate setae only preserved on frons. Head height: 439 µm, head width: 490 µm, head length: 401 µm. Ocelli large and very close to each other: median ocellus nearly adjacent to lateral ocelli, lateral ocelli medially separated by about their own diameter. IOD:OOD = 0.71. Eyes large, with multiple scattered punctures, eye height: 243 µm, eye width: 192 µm. Malar space very narrow, 58 µm, malar sulcus absent. Occipital carina complete, horseshoe-shaped, anteriorly marked by small punctures. Clypeus narrow, laterally with enlarged anterior tentorial pits, dorsally marked by distinct and curved epistomal sulcus. Mandibles narrow, two-toothed, leaving small, semicircular area from ventral clypeal margin. Area covered by labrum. Toruli dorsally oriented, positioned on moderately protruding antennal shelf, about half-way upon face. Antennal shelf almost effaced between toruli. Antennal shelf completely smooth without any wrinkles. Antennal shelf not connected to epistomal sulcus by sulci. Supraclypeal area not defined and not expanded. Single median pit present behind toruli. Antenna incompletely preserved. Probably 12-segmented. Left antenna broken off after eighth antennomere, three additional antennomeres preserved. Right antenna broken off after pedicel, five additional antennomeres preserved. Antenna elbowed with elongate scape. Scape surpassing head height. First flagellomere cylindrical distinctly longer than subsequent antennomeres (except clava). Subsequent antennomeres narrowed at base and laterally rounded, each antennomere about as long as wide or slightly longer. Clava about twice as long as previous antennomere. Scape with multiple punctures and few preserved setae. Remaining antennomeres with few scattered punctures.

Pronotum adjacent to mesoscutum. Pronotum with long and distinct neck, dorsal pronotal surface short, not visible in dorsal view. Distinct transverse pronotal sulcus present between pronotal neck and dorsal surface. Pronotal neck with irregular striae in posterior half. Posterior margin of pronotum with transverse row of punctures corresponding to distinct internal ridge that articulates with anterior margin of mesoscutum and laterally connects with postspiracular apodemes. Pronotum laterally to neck with distinct patches of short setae extending to lateral surface of propleura. Lateral panel of pronotum large and triangular, adjacent to mesopleuron. Pronotal depression for accommodation of profemur present. Hind corner of pronotum reaching tegula. Mesothoracic spiracles positioned at lateral margin of pronotum, on spike-like protuberances, spiracles posteriorly enclosed by prepectal shelf, dorsally reaching tegula. Mesothoracic spiracles completely enclosed by cuticle. Propleura smooth, posterior margin with narrow rectangular fields. Fields anteriorly and laterally carinate, serving as articulation point for anterior surface of procoxae. Articulation of procoxae further enhanced by two rounded impressions on rectangular prosternum, by distinct procoxal impressions on ventral mesopleuron and by ventrally flattened expansions of pronotum laterally to procoxal foramina. Prosternum without cross carina. Two submedian pits present in dorsalmost part of prosternum. Profurca u-shaped, profurcal arms only preserved as thin structures. Propleural arms incompletely preserved.

Mesonotum dorsally flattened. Mesoscutum wider than long, smooth, with few scattered elongate setae arising from punctures. Additional setae arranged in lines flanking both sides of each notaulus. Notauli present as very broad, curved sulci, which are distinctly dilated posteriorly. Notauli anteriorly nearly reaching anterior mesoscutal margin and posteriorly nearly reaching transscutal articulation. Notauli internally rather weakly marked. Preaxilla smooth, with two carinae on surface, arising from anterior and antemedian mesonotal wing processes. Anterior carina articulating with anterior margin of tegula. Tegula huge and rounded, posteriorly reaching (and articulating with) axillular carina. Tegula laterally expanded, with smooth and flattened anterior surface. Transscutal articulation straight and complete. Mesoscutellum with few scattered setae. Scutoscutellar sulcus marked by two large kidney-shaped pits, which are medially separated by broad straight ridge. Pits internally rather weakly marked. Axillae narrow and smooth. Mesoscutellar disc laterally separated from axillula by distinct straight ridges. Hind margin of mesoscutellum distinctly foveolate. Posterior wing process broadened and blunt with smooth surface. Mesopleuron smooth and glabrous, mesofemoral depression absent. Mesepimeron with two longitudinal ridges connecting anterior and posterior mesopectal margin and separating long rectangular area. Epicnemial pit present and marked by carina, with dense pilosity. Sternaulus developed as medially interrupted carinate sulcus connecting epicnemial pit with posterior margin of mesopectus. Mesepisternum anteriorly with distinct procoxal depressions, which are medially separated by short and indistinct carina. Raised acetabular and mesotrochantinal carinae present, both medially interrupted. Each lateral portion of acetabular carina connected by faint longitudinal carina to lateral portion of mesotrochantinal carina. Mesodiscrimen not traceable. Two mesofurcal pits developed. Anterior pit present at interrupted area of acetabular carina, posterior pit present medially on mesotrochantinal plate just anterior to mesocoxal foramina. Mesocoxal foramina not completely enclosed by cuticle. Mesodiscrimenal lamella reaching close to anterior margin of mesopectus. Mesofurca with two solid bases, mesofurcal bridge complete with dorsal orientation.

Metascutellum with two distinctly raised blade-like lateral and less distinct median carina, metascutellum posteriorly expanded. Lateral panel of metanotum composed of anteriorly reduced foveae. Metapleuron anteriorly smooth, posteriorly coarsely reticulate. Metepisternum with distinct depressions for accommodating mesocoxae, and with distinct median carina (corresponding to metadiscrimen). Single metafurcal pit present anteromedially of metacoxal foramina, posterior to raised carina. Metacoxal foramina with lateral projections. Metafurca indistinct, u-shaped, completely fused to highly raised paracoxal ridge. Metadiscrimenal lamella reaching mid-level of metacoxal foramina. Median keel on propodeum formed by v-shaped median carina pointing dorsally. Anterior margin of propodeum deeply excavate and smooth. Plicae developed, dorsal propodeal surface between plicae and median carina smooth. Posterior margin of propodeum deeply excavate, posterolateral corners strongly projecting and bifurcate. Hind margin of propodeum carinate.

Petiole cylindrical, laterally with long pilosity, 1.31 times as long as wide. Petiole with three dorsal, three lateral and one ventral carinae. Second tergum greatly enlarged, anterior margin with deep and broad median incision. Second tergum hardly overlapping petiole. Third and fourth tergum completely covered by second tergum, subsequent terga visible but extremely shortened. Second sternum greatly enlarged, covering at least one of subsequent sterna.

Wings: Unfolded but hardly traceable. Legs: All legs with elongate simple trochanters. Protibial spur with two apices but without distinct cleft. Midleg with two mesotibial spurs. Hind leg with two metatibial spurs.

Male unknown.

Comments: The fossils shares a number of morphological characters with the genus Ortona Masner and García22, which is restricted to the New World. It differs in the following characters: head not depressed, level of toruli lower than midpoint of eye, oral carina distinctly developed, labrum semicircular (not transverse), clava not long ovoid, and pronotal neck distinctly developed. These characters support placement in a new genus.

Tribal placement

The current subdivision of Diapriinae into three tribes (Spilomicrini, Psilini, and Diapriini) is supported by morphological data22. Xenomorphia resurrecta and X. handschini can be readily placed in the tribe Spilomicrini based on the presence of a syntergite on the metasoma, the presence of a distinct malar sulcus (faintly indicated only in female of X. handschini), the absence of spike-like, protruding mesothoracic spiracles, and the presence of complete notauli. Both species have retained a number of plesiomorphic characters, such as the high number of antennomeres (14) in both sexes, which is otherwise only known from the extant genera Xenismarus Oglobin and Chilomicrus Masner and García. These genera are characterized by a restricted, putatively relictual, Valdivian distribution22. A macrotergite (second tergum), instead of a syntergite (fused second and third tergum), and the presence of spike-like, protruding mesothoracic spiracles characterize Coptera anka and Palaeortona quercyensis as members of Psilini, a small tribe that comprises only four extant genera. Only the tribe Diapriini, which is considered the most derived lineage of Diapriinae22, is not represented in the Quercy fossil parasitoid fauna.