The superfamily Mantispoidea ‌Leach, 1815 includes three extant families – Berothidae ‌Handlirsch, 1906, Rhachiberothidae ‌Tjeder, 1959, and Mantispidae ‌Leach, 1815 – along with one extinct family, Dipteromantispidae ‌Makarkin, Yang & Ren, 2013 (Engel et al. 2018; Ardila-Camacho et al. 2021; Li et al. 2023, 2024; Wang et al. 2024). The monophyly of Mantispoidea is well supported by phylogenetic analyses based on both morphological and molecular data. However, the phylogenetic relationships between its families remain contentious, particularly regarding the placement of Rhachiberothidae and Mantispidae (Liu et al. 2015; Wang et al. 2017; Engel et al. 2018; Winterton et al. 2018; Vasilikopoulos et al. 2020; Ardila-Camacho et al. 2021).

The fossil record of Mantispoidea is diverse, comprising over 80 species from the Lower Jurassic to the Miocene (Jepson et al. 2018; Lu et al. 2020; Nakamine et al. 2020; Baranov et al. 2022; Hart et al. 2024). This superfamily appears to have diversified rapidly during the Angiosperm Terrestrial Revolution (Benton et al. 2022), likely driven by an increase in prey abundance, particularly angiosperm-feeding insects. However, this hypothesis requires further testing, as the diversity dynamics of the superfamily are still poorly understood.

Among the raptorial mantispoids, Dipteromantispidae are exclusively known from Cretaceous deposits, with fossils recorded in China, Myanmar, and the United States (e.g., Makarkin et al. 2013; Liu et al. 2017; Azar et al. 2020). The greatest species diversity for this family comes from mid-Cretaceous Kachin amber (e.g., Li & Liu 2020). Rhachiberothidae have a fossil record extending from the Cretaceous to the Eocene, with their highest diversity also found in mid-Cretaceous Kachin amber (e.g., McKellar & Engel 2009; Makarkin & Kupryjanowicz 2010; Nakamine et al. 2020). The Mantispidae fossil record begins in the Jurassic, with the youngest occurrences documented in the Miocene (e.g., Khramov 2013; Hart et al. 2024). Like the other two families, Mantispidae fossil diversity is concentrated in mid-Cretaceous Kachin amber (e.g., Lu et al. 2020; Li et al. 2023). This exceptionally high diversity during the mid-Cretaceous likely reflects a Lagerstätte effect, influenced by the abundance of amber deposits worldwide and sedimentary deposits in Asia (e.g., Jepson et al. 2013; So & Won 2022; Delclòs et al. 2023).

The family Mantispidae includes two extinct subfamilies (Mesomantispinae Makarkin, 1996 and Doratomantispinae Lu, Wang, Zhang, Ohl, Engel & Liu, 2020) and four extant subfamilies (Symphrasinae ‌Navás, 1909, Drepanicinae Enderlein, 1910, Calomantispinae Navas, 1914, and Mantispinae Leach, 1815) (Lai et al. 2024). The taxonomic position of Symphrasinae has been debated for decades, with conflicting results in the literature. Some researchers have placed it within Rhachiberothidae (e.g., Ardila-Camacho et al. 2021), while others classify it under Mantispidae (e.g., Liu et al. 2015; Li et al. 2024), or alternate between both families depending on the dataset analyzed (Cai et al. 2023). In this study, we provisionally follow the classification of Symphrasinae within Mantispidae (e.g., Lai et al. 2024), but emphasize the need for increased sampling and the generation of genomic data for Mantispoidea to resolve this issue.

Additionally, the discovery of more fossil taxa could help clarify the placement of Symphrasinae by providing further morphological evidence. Describing new taxa from deposits outside the most commonly studied regions (e.g., Kachin or Baltic ambers) could shed light on the past diversity of the family, refine the boundaries of its constituent lineages, and assess the diagnostic characters used to distinguish crown and stem groups. Following this approach, we describe the first representative of Symphrasinae from Cenomanian Charentese amber.

The Charentes region in southwestern France has the highest concentration of amber deposits in France; most of them are of Albian or Cenomanian age (Perrichot et al. 2007a, 2010; Néraudeau et al. 2020). The piece of amber and specimen studied herein were found in the lignitic layers of the Font-de-Benon quarry, near the villages of Archingeay and Les Nouillers, which are dated as latest Albian-earliest Cenomanian (Néraudeau et al. 2002; Dejax & Masure 2005; Peyrot et al. 2019). The amber piece was collected from level A1sl-A (= A1sl2 sensu Néraudeau et al. 2002) of the ‘lithological subunit A1’, consisting of lignitic sand and clay lenses that range from 0.1 to 1 m in thickness (Fig. 1; see also ‘Arc1’ in Kania-Kłosok et al. 2022: fig. 1B). The resin pieces and the associated fossil woods were deposited, after short biostratinomic transport (parautochthony), in a coastal marine area, as indicated by sedimentary figures of tides and bioturbation, and the presence of oysters, teredinid bivalve holes in the woods, and marine foraminifera in the lignitic clay (Néraudeau et al. 2002; Perrichot 2005). However, the reduced abundance of burrows and oysters in amber levels suggests environments under continental influence (freshwater): the facies are compatible with those of an internal estuary (Dalrymple et al. 1992). Wood remains from Charentese amber outcrops have been associated with the morphogenera Agathoxylon ‌Hartig, 1848, Brachyoxylon ‌Hollick & Jeffrey, 1909, Podocarpoxylon ‌Gothan, 1905, and Protopodocarpoxylon ‌Eckhold, 1922, and the resin-producing tree has been related to Araucariaceae ‌Henkel & W.Hochst. or Cheirolepidiaceae ‌Turutanova-Ketova (Nohra et al. 2015).

The piece of amber was polished using thin silicon carbide papers on a Buehler Metaserv 3000 polisher and then embedded in epoxy resin (Araldite© 2020). The specimen was examined with a Zeiss Axio Zoom V16 stereomicroscope with an attached Zeiss AxioCam 512 color camera. All images are digitally stacked photomicrographic composites of several individual focal planes, which were obtained using Helicon Focus 6.7. The figures were composed with Adobe Illustrator CC2018 and Photoshop CC2018.

The nomenclature of the wing venation is adapted from Li et al. (2023), and the nomenclature of the legs follows Ardila-Camacho et al. (2024). The holotype IGR.ARC-399 is housed in the Geological Department and Museum of the University of Rennes, France (IGR).

We follow standard wing venation terminology and abbreviations, as follows:

The new fossil is readily assignable to the raptorial Mantispoidea (i.e. Rhachiberothidae, Dipteromantispidae, and Mantispidae) based on its distinct raptorial fore legs (Figs 2; 3). It can be excluded from Dipteromantispidae, as that family is characterized by reduced hind wings (only the fore wings are developed in Dipteromantispidae), whereas this specimen has fully developed fore- and hind wings (e.g., Makarkin et al. 2013; Li et al. 2020, 2023). Similarly, it cannot be placed in Rhachiberothidae (e.g., Jouault 2022; Li et al. 2023), which are currently divided into two valid subfamilies, Paraberothinae Nel et al., 2005 (paraphyletic) and Rhachiberothinae Tjeder, 1959. Paraberothinae can be distinguished from Rhachiberothinae by the presence of at least two (and usually numerous) spines on the inner edge of the protibia, and the absence of the crossvein 2scp-r on the fore wing (Nakamine et al. 2020). Thus, if the specimen belongs to Rhachiberothidae, it would likely be classified under Rhachiberothinae. However, the morphology and wing venation of the new specimen exclude this possibility. According to the recently revised diagnosis of Rhachiberothinae by Li et al. (2023), the new specimen differs in key features: its profemur stout (vs weakly incrassate in Rhachiberothinae), its protarsus 4-segmented (vs 5-segmented, although sexually dimorphic), its fore wing with more than one trichosors between each adjacent veinlets (vs only one), at least three ra-rp crossveins (vs one or two), M fused with R for a long distance distad 1m-cu (vs separated from R proximad 1m-cu), and the hind wing with a sigmoid 1r-m crossvein (vs upright). Therefore, the new specimen cannot be placed in either Paraberothinae or Rhachiberothinae.

The new specimen possesses most of the diagnostic character states proposed by Li et al. (2023) to delineate the mantispid subfamily Symphrasinae. It can be easily distinguished from Doratomantispinae by the configuration of its profemoral spines, which are extremely long and often bifurcated in doratomantispine species (e.g., Lu et al. 2020; Jouault et al. 2022; Li et al. 2020, 2022). Additionally, the new specimen differs from Mesomantispinae by the ScP and RA fused distally (vs not fused in Mesomantispinae) and by fewer branches on the CuA of the fore wing (vs profusely and pectinately branched) (Jepson et al. 2018; Lu et al. 2020). Affinities with Mantispinae and Calomantispinae are excluded due to the specimen’s broad wings, with numerous RP veins, the ScP not meeting C, and its overall pattern of the wing venation (e.g., Snyman et al. 2018; Reynoso-Velasco & Contreras-Ramos 2019). The diagnosis of Drepanicinae was recently revised (Lu et al. 2020), several diagnostic features for that subfamily are absent in the new specimen: fore femur with one row of integumentary processes present (vs with at least two rows of integumentary processes in the new specimen); trichosors usually absent or occasionally present and restricted to wing apex (vs trichosors present along the entire wing margin); fore wing at most with a suggestion of recurrent humeral veinlet (vs fore wing with a humeral veinlet). Therefore, the specimen cannot be assigned to Drepanicinae. Its classification within Symphrasinae is further supported by the configuration of its tarsomere I, which is spine-like, its tarsomere II arising midway, and the absence of a basal integumentary process (i.e., a prominent basal spine) (Lu et al. 2020; Ardila-Camacho et al. 2024).

Currently, the genera Sinomesomantispa, Parasymphrasites, Archaeosymphrasis, ‌Proplega, Parvosymphrasites, Symphrasites, and Habrosymphrasis are considered as part of the stem groups of Symphrasinae (Wedmann & Makarkin 2007; Lu et al. 2020; Shi et al. 2020; Li et al. 2023). In a recent cladistic analysis, the genus Clavifemora ‌Jepson, Heads, Makarkin & Ren, 2013, was found to be sister group to the rest of Symphrasinae (Li et al. 2024). However, it is currently classified within the subfamily Mesomantispinae ‌(Jepson et al. 2013). Only the genus Haplosymphrasites is classified within the crown group of Symphrasinae, due to the presence of two to four trichosors between longitudinal veins along the distal wing margin (Lu et al. 2020). This character, which is also found in the new specimen, supports its placement within the crown group of Symphrasinae (Fig. 3E). Thus, the crown group of Symphrasinae now includes Haplosymphrasites, the new genus described herein, and the extant genera Anchieta, Plega, and Trichoscelia ‌(Ardila-Camacho et al. 2024).

We are grateful for suggestions from three anonymous reviewers, which have improved the earlier version of the manuscript. We warmly thank the Marchand family for permitting access to the Font-de-Benon quarry and collection of amber. We are also grateful to Didier Néraudeau for his efforts and multiple contributions to the collection and study of Charentese amber.

The authors have declared that no competing interests exist.

No ethical statement was reported.

Partial support for fieldwork in Charentes was provided by the French National Research Agency (ANR) through project AMBRACE (no. BLAN07-1-184190 to D. Néraudeau, Géosciences Rennes).

Conceptualization: CJ and VP; Investigation: CJ and XL; Resources: VP; Writing – original draft preparation: CJ; writing – review and editing: CJ, XL, VP; visualization: CJ; supervision: VP; project administration: CJ and VP; funding acquisition: VP. All authors have read and agreed to the published version of the manuscript.