The holotype is deposited in the Natural History Museum of the Lebanese University, Faculty of Sciences II, Fanar, Lebanon. The amber was cut, ground and polished and then included between two cover slips with Canada balsam medium as described by Azar et al. (2003). Terms for morphological structures follow Huber and Sharkey (1993). The descriptive terms “tubular”, “nebulous” and “spectral” for reduced wing venation are used in accordance to Mason (1986). In the descriptions, all veins are tubular veins unless otherwise noted. Measurements always refer to the maximum width or length of the respective body parts. Habitus images (Fig. 1 and Fig. 2) were taken with a Leica DXM 1200 digital camera attached to a Leica MZ 16 APO microscope and processed using Auto-Montage (Syncroscopy) software. Images of selected body parts (Fig. 2b,d) and all measurements were done under a Keyence VHX 600 digital microscope under the highest possible magnification for the respective measurement (up to 2.500 ×). Digital drawings of wing venation and habitus (Fig. 1 and Fig. 2) were done with a Wacom Bamboo Pen Tablet in Adobe Illustrator CS5 on the basis of digital photographs. Images were edited with Adobe Photoshop CS3 and figure plates assembled with Adobe Illustrator CS5.

Family Spathiopterygidae Engel and Ortega-Blanco, 2013.

Included genera: Diaspathion Engel and Huang, 2015; Mymaropsis Engel and Ortega-Blanco, 2013; Spathiopteryx Engel and Ortega-Blanco, 2013; Spathopria Engel, Ortega-Blanco and Grimaldi, 2013.

Diagnosis: See Engel et al. (2013) for male characters. Female characters: Antenna 14-segmented (female:male antennal segments 14:14), flagellomeres apically without curved trichoid sensilla. Metasoma distinctly longer than head plus mesosoma. Last tergum (Mt8) tubularly expanded with apical cerci. Hypopygium situated close to apex of metasoma.

Genus Mymaropsis Engel and Ortega-Blanco, 2013.

Type species: Mymaropsis turolensis Engel and Ortega-Blanco, 2013.

Diagnosis: Frontal shelf weakly developed. Forewing densely covered with short setae, with well-defined, tubular vein (M + Cu) near wing base, distally forked into an anterior (M + Rs) and a posterior branch (Cu). Hindwing with small portion of membrane and three distal hamuli. Metasoma with second tergum largest. See Engel et al. (2013) for full diagnosis.

Mymaropsis baabdaensis sp. n. (Fig. 1 and Fig. 2).

Holotype: ♀: No. 855, deposited in the Natural History Museum of the Lebanese University, Faculty of Sciences II, Fanar, Lebanon.

Age and outcrop: Lower Cretaceous, Ante-Jezzinian = pre-Upper Barremian–Lower Bedoulian (Maksoud et al., 2014), amber of Hammana-Mdeyrij, Caza Baabda, Mohafazat Jabal Loubnan, Central Lebanon, Lebanon.

Description: ♀: Specimen dark brown to black. Head, mesosoma and metasoma largely devoid of setation. Head and metasoma with fine reticulation, metasoma smooth. Total body length: 0.92 mm, head plus mesosoma: 0.42 mm. Head subglobose, head height 0.24 mm, head length 0.17 mm. Eye height 0.17 mm, eye width 0.12 mm. Antenna inserted low on head, slightly above level of ventral eye margin. Frontal shelf present but indistinct. Antenna 14-segmented, antennomeres densely covered with thin setae (Fig. 2b), longitudinal setae and curved trichoid sensilla absent. Scape ventrally slightly expanded, about twice the length of pedicel. F1-F4 thin and cylindrical, F5-F11 distinctly broader rectangular or subquadrate, F12 elongate, slightly pointed at apex. F5-F12 pedunculate. Length:width of individual antennomeres (in μm): scape 105:46, pedicel 54:37, F1 61:19, F2 59:20, F3 50:20, F4 52:22, F5 45:30, F6 42:31, F7 50:40, F8 49:42, F9 48:38, F10 49:40, F11 53:38, F12 90:32.

Mesosoma very stout, as long (0.27 mm) as high (0.27 mm): Pronotum extremely shortened, hardly visible in dorsal view. Mesonotum not flattened. Propodeum shortened.

Forewing hyaline with sparse setation (Fig. 1a). Outer margin with short fringe. Forewing length 1.05 mm, forewing width 0.44 mm. Stronger setation along spectral veins (Fig. 1b). Forewing venation reduced (Fig. 1b): C absent, Sc + R (“submarginal vein”) very close to basal part of anterior wing margin, leaving only very small membranous area between Sc + R and anterior wing margin. Pterostigma (Pst) present and evenly thickened (“marginal vein”), 112 μm long, 23 μm broad, appressed along anterior wing margin. A short vein R1 (“postmarginal vein”) emerges distally from pterostigma, 106 μm long. Radial cell (R) present; 150 μm long, posteriorly delimited by rather strong vein M + Cu, that forks into an anterior short vein M + Rs ending in the pterostigma and a posterior vein Cu of similar length terminating just before the posterior wing margin. More distally a spectral vein emerges from the point of separation between M + Rs and Cu. This spectral vein seems to correspond to Rs + M. It is distally forked into an anterior branch Rs and a posterior branch M, both being spectral. Two additional spectral veins of unknown origin are running parallel to M (marked with question marks in Fig. 1b). Posterior to M + Cu, is a short nebulous vein parallel to posterior wing margin that corresponds to vein A. Hindwing extremely shortened, with membrane, hindwing length 97 μm, hindwing width 10 μm. Hindwing without wing venation apart from Sc + R, three hamuli present (Fig. 2a).

Legs with all trochanters distinctly enlarged (Fig. 2c). Leg dimensions (in μm): Foreleg: coxa 90, trochanter 70, trochantellus 22, femur 77, tibia 93, tarsus 248 (basitarsus 94). Midleg: coxa 70, trochanter 52, trochantellus 20, femur 89, tibia 137, tarsus 252 (basitarsus 99). Hindleg: coxa 57, trochanter 84, trochantellus 41, femur 178, tibia 153, tarsus 307 (basitarsus 152). Protibial spur curved with distinct apical cleft (Fig. 2d), 46 μm long, protarsal comb well developed. Hindtiba with single hindtibial spur, 42 μm long.

Metasomal length 0.51 mm, metasomal height 0.26 mm. Metasoma not collapsed with eight visible tergites, 2nd metasomal tergite the longest and ovipositor slightly expanded (Fig. 2c). Last tergum (Mt8) tubularly expanded with apical cerci. Length of metasomal tergites in dorsal view (in μm): Petiole (Mt1) 93, Mt2 229, Mt3 32, Mt4 36 (separation line between Mt3 and Mt4 difficult to discern), Mt5 38, Mt6 53, Mt7 39, Mt8 61. Length of exposed part of ovipositor 43 μm. Hypopygium situated close to apex of metasoma.

♂: Unknown.

Etymology: The new species is named after the Baabda District in Lebanon where the amber specimen was found.

The superfamily Diaprioidea (sensu Sharkey, 2007) is a subunit of Proctotrupomorpha which has been consistenly retrieved by molecular data (e.g., Castro and Dowton, 2006, Dowton and Austin, 2001, Heraty et al., 2011 and Sharkey et al., 2012) but not in the morphological analysis of Vilhelmsen et al. (2010). Monophyly of Diaprioidea might be supported by the presence of a distinct frontal extension forming a shelf below the antennal foramina. This character was originally proposed by Early et al. (2001) as putative synapomorphy of Diapriidae, Maamingidae and Monomachidae, even though it is less distinctly developed in the latter family and lacking in the former diapriid subfamily Ismarinae, which was elevated to family rank by Sharkey et al. (2012). The frontal shelf is also not very distinct in Spathiopterygidae but its presence still seems to be the only character supporting a phylogenetic placement in or close to Diaprioidea. This placement is currently tentative and needs to be tested by future phylogenetic studies. Engel et al. (2013) suggested a sister group relationship between Maamingidae and Spathiopterygidae based on the absence of an occipital carina and the absence of an enlarged petiole. The phylogenetic significance of the petiole is limited due to its homoplastic nature and also the occipital carina (which we cannot exclude with certainty from our fossil due to its head orientation) was convergently reduced numerous times within Proctotrupomorpha, e.g., in Maamingidae, Mymarommatidae and several groups of Chalcidoidea and may or may not be indicative of a sister group relationship between Spathiopterygidae and Maamingidae. A careful comparative study of morphological characters throughout Proctotrupomorpha would be needed to better define Diaprioidea and to infer the phylogenetic position of Spathiopterygidae relative to other diaprioid and proctotrupomorphan lineages.

The forewing venation of Mymaropsis baabdaensis is similar to that of Mymaropsis turolensis in the presence of a well defined, tubular vein (M + Cu) near the wing base, distally forked into an anterior (M + Rs) and a posterior branch (Cu). These veins are spectral or absent in other Spathiopterygidae. Also vein A seems to be more sclerotized in Mymaropsis than in other Spathiopterygidae. Mymaropsis is also the only spathiopterygid genus with a membranous hindwing, which is completely absent or reduced to a veinal stub in the other genera. All of the above-mentioned wing characters seem to represent the plesiomorphic condition in Mymaropsis relative to the apomorphic reductions found in the other genera. The morphological evidence therefore agrees well with the fact that Mymaropsis is currently the earliest known genus of Spathiopterygidae.