Research Article |
Corresponding author: Yingying Cui ( cuiying19860105@gmail.com ) Corresponding author: Dong Ren ( rendong@mail.cnu.edu.cn ) Academic editor: Hui-ting Wu
© 2024 Nan Yang, Yingying Cui, Ziqiang Xu, Yanqi Xu, Dong Ren, Olivier Béthoux.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Yang N, Cui Y, Xu Z, Xu Y, Ren D, Béthoux O (2024) The first Permian Diaphanopterodea (Insecta, Megasecopteromorpha) from China. Fossil Record 27(2): 247-258. https://doi.org/10.3897/fr.27.e128892
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A new Diaphanopterodea (Insecta, Palaeoptera, Megasecopteromorpha), Sinoelmoa yangquanensis gen. et sp. nov., is described based on a single specimen discovered from the Shuiquan Gully locality (Shanxi Formation; Permian, Cisuralian, Asselian; China). A broad comparative analysis of the wing venation of the known members of the diaphanopterodean families Parelmoidae and Elmoidae allowed assigning the new taxon to the former family. This new occurrence represents the first record of a Permian Diaphanopterodea from China, and both the earliest and most oriental record for the Parelmoidae. It sheds new light on the distribution and diversity of these extinct taxa.
Asselian, Cisuralian, China, Diaphanopterodea, Fossil insect, North China Block, Parelmoidae
The insect order Diaphanopterodea, a member of the broader taxon Megasecopteromorpha Béthoux, 2020 in
One of the best documented families is the Parelmoidae Rohdendorf, 1962, composed of various Cisuralian (i.e. lower Permian) genera and species from Czech Republic (Obora; Sakmarian), USA (Elmo & Midco; Artinskian), France (Lodève; Kungurian) and Russian Federation (Chekarda; Kungurian). Here, we describe a new, isolated wing discovered from the Shuiquan Gully, Shanxi Formation (China; Asselian), which can be confidently assigned to this family. Our broad comparative analysis suggests that it belongs to a previously unknown genus and species. It constitutes the first record of Permian Diaphanopterodea from China.
The new material (specimen YQZYW 15) was collected from the siltstone layer of the middle Shanxi Fm., in a rock profile at Duanjiabei District, Yanquan, Shanxi Province, North China (Fig.
Geographic and stratigraphic information on the Shuiquan Gully locality (red triangle). A–C. Location of the collecting site, on A. The palaeogeographic map of early Permian (Cisuralien); B. The map of Shanxi Province, China; C. The map of Shuiquan Gully locality, Yangquan City. D. Chronological framework of the Early Permian strata according to Shen S. et al. (2020), Shen B. et al. (2022) and
The new material (specimen YQZYW 15) is housed at Yangquan City Planning and Natural Resources Bureau (Geological Specimen Room). It was photographed using a Nikon SMZ25, and a Canon 5DS coupled with a Canon MP-E 65 mm macro lens, under both dry and ethanol conditions. Photographs of this specimen reproduced herein are the result of a combination of photographs taken under both dry (best-preserved side) and ethanol conditions (both sides) (‘eth-eth-dry’ composite).
New photographs of material housed at the Museum of Comparative Zoology (
Wing venation of representatives of Parelmoidae Rohdendorf, 1962. A–D. Representatives of the genus Parelmoa Carpenter, 1947. A. Parelmoa revelata Carpenter, 1947, holotype, specimen
New photographic data on the specimen Ld LAP 365 (Musée of Lodève, France) were also collected. Two reflectance transformation imaging (RTI) files were generated based on photographs taken using a ~30 cm diameter, automated light dome driving a Canon EOS 5DS digital camera, itself coupled to a Canon MP-E 65 mm macro lens. The first file provides an overview of the side Ld LAP 365a, while the second file is focused on the wing base of the side Ld LAP 365b (each based on a set of 42 photographs). Original photographs were optimized using Adobe Photoshop CS6 prior to RTI processing, itself achieved using the RTI builder software (Cultural Heritage Imaging). We provide an online Dryad dataset (
In addition to photographs, hand-drafted drawings were also produced. For the
We follow the serial insect wing venation groundplan and the associated wing venation nomenclature (
Taxon Rostropalaeoptera Kukalová-Peck, 2000 in Wootton & Kukalová-Peck (2000)
Taxon Megasecopteromorpha Béthoux, 2020 in
Commonly among Megasecopteromorpha, and more particularly in Diaphanopterodea, MA shows some degree of connection with RP. It ranges from a connection via a strong cross-vein, shortly after the origin of MA, to a full fusion with R, then continuing along RP, from which MA diverges at some stage. Because Diaphanopterodea also exhibit oblique cross-veins, it can sometimes be difficult to determine whether an oblique structure occurring between RP and MP is the genuine MA or a cross-vein. Unlike previous authors (
Wing venation of Elmoa trisecta Tillyard, 1937 (Elmoidae Tillyard, 1937). A. Specimen
Parelmoa Carpenter, 1947.
Diapha Kukalová-Peck, 1974; Elmodiapha Kukalová-Peck, 1974; Paradiapha Kukalová-Peck, 1974; Permelmoa Prokop & Nel, 2011; Permodiapha Kukalová-Peck, 1974; Permuralia Sinichenkova & Kukalová-Peck, 1997; Protodiapha Kukalová-Peck, 1974; Pseudelmoa Carpenter, 1947; Stenodiapha Kukalová-Peck, 1974; Sinoelmoa gen. nov.
ScP long, ending beyond the first fork of RP (plesiomorphy within Diaphanopterodea); near wing base, shortly after its origin, CuA fused for some distance with, or running closely along, R+M (apomorphy; as currently documented, shared with all Diaphanopterodea except Sinodiaphidae, in which CuA is connected with M by a short cross-vein, and Diaphanopteridae, in which the connection of CuA and M is very brief); first cross-vein in the CuA–CuP area very short and oblique, with CuA displaying a clear inflexion at the point of connection with this cross-vein [also present in Diaphanopteridae, Carrizodiaphanoptera and, to some extent, Elmoidae (Fig.
The combination of (i) an overall rich venation, (ii) a long fusion of CuA with R+M (or, CuA running very close to R+M for some distance), and (iii) a cua-cup cross-vein very short, is generally used to identify members of the Parelmoidae. The Pennsylvanian Diaphanopteridae differ from this family only by lacking character state (ii) (see
Notably, a distal fork of CuP is common in the Obora material, with some specimens displaying an early fork, and even a 3-branched CuP. The relation between RP and MA is also very variable across the corresponding species, ranging from a complete lack of fusion to a long one. In contrast, species of the genus Parelmoa Carpenter, 1947 (Fig.
Sinoelmoa yangquanensis Yang, Cui, Xu & Béthoux, sp. nov.
Named after the ancient Greek prefix Sino- (China), and the genus Elmoa.
Type species only.
By monotypy, same as for the type species.
YQZYW 15, part and counterpart.
Named after the Yangquan city where the Shuiquan Gully locality is located.
The specimen was collected at the Shuiquan Gully locality; Shanxi Formation, Permian, Cisuralian, Asselian (Shen S. et al. 2020; Shen B. et al. 2022); near Yangquan City, Shanxi Province, China.
Area between anterior wing margin and R/RA dark; ScP vanishing in the area between anterior margin and R/RA; MA/MP split opposite the RA/RP split (as opposed to MA/MP split well distal of RA/RP split); CuP forked; AA long (as opposed to AA short), ending on posterior margin beyond wing mid-length.
Positive and negative imprints of a right forewing, distal part missing; dark area between anterior margin and R/RA; near wing base, preserved anterior wing margin very oblique, suggestive of the presence of a short portion of ScA distinct from the anterior wing margin (see Fig.
Sinoelmoa yangquanensis gen. et sp. nov., holotype, specimen YQZYW 15. A. Overview, drawing and photograph (dry-eth-eth composite; dashed line delimiting the area missing on side a) of right forewing. B. Detail of the course of CuA, drawing and photograph (eth-eth-dry composite), as located in A.
Preserved wing length 15.4 mm, width 5.5 mm.
The presence of a very short cua-cup cross-vein allows assigning the new specimen to the Diaphanopterodea and, within this taxon, allows excluding affinities with the Sinodiaphidae. Furthermore, the derived state ‘long fusion of CuA with R+M (or, CuA running very close to R+M for some distance)’ allows excluding the new material from the Diaphanopteridae. Then, an assignment to the Parelmoidae as delimited above is straightforward. Nevertheless, a possible assignment to the family Elmoidae was also considered. Two main character states allow distinguishing members of this family (Fig.
Within the Parelmoidae, the extent of the AA area is a useful character to consider first. This area is distinctively long in the new material, a state shared with Elmodiapha (see
Permelmoa magnifica Prokop & Nel, 2011, from the Lodève locality (France; Cisuralian, Kungurian), is also currently assigned to Parelmoidae. To better assess the affinities of the new material we carried out new observations of the material of this species (Fig.
Wing venation of Permelmoa magnifica Prokop & Nel, 2011 (Parelmoidae Rohdendorf, 1962), holotype specimen Ld LAP 365, right forewing. A. Interpretative drawing under interpretation favoured herein (dotted line, twin imprints of vein sections; and see text), photograph (RTI extract), and normals visualization (RTI extract). B, C. Detail of the radial and median systems, as located in A, under the interpretation followed by
In summary, it is legitimate to erect a new genus and species for the new material.
Thanks to its good preservation, the material of Sinoelmoa yangquanensis gen. et sp. nov. allows addressing some uncertainty of the course of main veins near the wing base in Diaphanopterodea. Except for the Sinodiaphidae and Diaphanopteridae, the area between the Cu stem and R+M is very narrow in these insects; and, concurrently, the distal free portion of CuA clearly diverge in the close vicinity of the split of R+M (into R and M). Up to now, this situation made it difficult to clearly assess whether the entire stem of Cu, or CuA only, fuses with R+M (and, if so, at which point the (R+M)+CuA fusion takes place). In the newly described specimen a Cu stem independent from R+M is clearly visible; and a simple CuA diverges from it, runs along R+M for some distance, and then diverges abruptly opposite the bending of R+M, just basal of the R/M split (Fig.
The discovery of Sinoelmoa yangquanensis gen. et sp. nov. has also relevance regarding the age and distribution of the Parelmoidae. Being Asselian in age, it composes the earliest occurrence of the family, but also the most oriental one, along the eastern margin of the Palaeothetys, on the North China Block. This new record suggests that these rather infrequent insects may have had a large distribution, at least along the lower latitudes of the Northern Hemisphere.
Conceptualization, Y.C., D.R. and O.B.; investigation, N.Y., Z.X., Y.X. and O.B.; resources, D.R.; writing—original draft preparation, Y.C., N.Y. and O.B.; writing—review and editing, Y.C., N.Y., D.R. and O.B.; visualization, Y.C., N.Y., Z.X. and O.B.; supervision, Y.C.; project administration, Y.C.; funding acquisition, Y.C., D.R. All authors have read and agreed to the published version of the manuscript.
We are grateful to Markus Poschmann (Direktion Landesarchäologie/Erdgeschichtliche, Koblenz) and Pavel Sroka (Institute of Entomology, České Budějovice) for their constructive comments and to the editorial board of Fossil Record for handling the reviewing process. We are grateful to Zhijun Bai (Geological Hazard Prevention and Control Center of Yangquan City) for collecting the holotype and providing the paleogeographic information composing Fig.