Research Article |
Corresponding author: Michael S. Engel ( msengel@ku.edu ) Academic editor: Kees van Achterberg
© 2018 Michael S. Engel, Diying Huang, Chenyang Cai, Abdulaziz Alqarni.
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:
Engel MS, Huang D, Cai C, Alqarni AS (2018) A new lineage of braconid wasps in Burmese Cenomanian amber (Hymenoptera, Braconidae). ZooKeys 730: 75-86. https://doi.org/10.3897/zookeys.730.22585
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A new braconid wasp from the Upper Cretaceous (Cenomanian) amber of the Hukawng Valley in Kachin State, Myanmar is described and figured from a unique female. Seneciobracon novalatus Engel & Huang, gen. et sp. n., is placed in a distinct subfamily, Seneciobraconinae Engel & Huang, subfam. n., owing to the presence of a unique combination of primitive protorhyssaline-like traits, with an otherwise more derived wing venation. The fossil is discussed in the context of other Cretaceous Braconidae.
Cretaceous, Euhymenoptera , fossil, Ichneumonoidea , Myanmar, parasitoid, taxonomy, wasp
Although braconids are a frequently encountered lineage in the modern hymenopteran fauna (
Here we describe a new genus and species of braconid wasps in Burmese amber (Fig.
A small flake of Upper Cretaceous amber from Myanmar was discovered to contain a tiny braconid wasp, which is here designated as the holotype for the species described. The chip of amber is 8.9 mm at its maximum length, 5.4 mm in maximum width, and approximately 1.7 mm deep. While flat surfaces could be polished on the larger planes, permitting lateral views of the specimen, the narrow edges are rough and could not be cleaned further owing to the close proximity of the wasp’s anterior end near one border (Fig.
We document the present fossil in the interest of elaborating character combinations of Cretaceous Braconidae and in the hopes that these will ultimately aid our resolution of basal relationships among lineages of braconids, with descriptive work such as this forming the basis for such discovery (sensu
Seneciobracon Engel and Huang, gen. n.
Head orthognathous, cyclostome; clypeus shorter than wide, protruding; hypoclypeal depression deep (Fig.
Seneciobracon novalatus Engel & Huang, sp. n.
As for the subfamily (vide supra).
The new generic name is a combination of the Latin senecio, meaning, “old man”, and Bracon Fabricius, type genus of the family. The gender of the name is masculine.
♀ (Fig.
As for the subfamily (vide supra).
♀: Total length 2.0 mm (as preserved, excluding ovipositor); forewing length 1.50 mm, hind wing length 1.35 mm; integument dark brown (Fig.
Head apparently longer than broad (direct facial view not possible, observable in frontal-oblique view: Fig.
Mesosoma length 0.75 mm; pronotal collar distinct; pronotal surface smooth, dorsope and laterope absent; mesoscutum smooth, raised above pronotum; notauli deeply impressed, simple, percurrent but not meeting; lateral areas of mesoscutum (lateral to notauli) distinctly raised, convex; mesoscutellar sulcus deeply impressed, simple; mesoscutellum slightly raised, convex, smooth; mesopleuron smooth; propodeum areolate. Legs slender, with numerous setae; metafemur swollen; tibial spurs short, protibial calcar slightly curved, without comb; tibiae without spines or peg-like setae; metatibia length 0.63 mm; basitarsi largest tarsomeres, but shorter than combined length of remaining tarsomeres; pretarsal claws short, simple; arolium small. Forewing (Fig.
Metasoma length 1.0 mm; terga with integument transversely wrinkled, otherwise impunctate, with sparse, minute setae; sterna apparently smooth and impunctate; tergum I about as long as wide, terga II and III apparently longer than wide, fused; remaining terga transverse; dorsope of tergum I apparently absent; ovipositor long, straight, shorter than metasoma when exerted, length 0.80 mm; ovipositor sheaths slightly broader apically, with abundant minute setae.
♂: Latet.
The specific epithet is a combination of the Latin novus, meaning, “new”, and alatus, meaning, “wing”, and is a reference to the more derived wing venation relative to other Cretaceous amber Braconidae (e.g., the protorhyssalines and Aenigmabracon Perrichot et al.).
The new subfamily is most similar to the modern, putatively primitive Rhyssalinae, and the tribe Rhyssalini in particular (
Aside from S. novalatus, there have hitherto been 11 Cretaceous amber Braconidae described – Archephedrus stolamissus Ortega-Blanco et al. and Protorhyssalopsis perrichoti Ortega-Blanco et al. in Albian Spanish amber; Archaeorhyssalus subsolanus Engel and Rhetinorhyssalus morticinus Engel in Cenomanian Burmese amber, Protorhyssalodes arnaudi Perrichot et al. and Aenigmabracon capdoliensis Perrichot et al. in Cenomanian amber from France; Protorhyssalus goldmani Basibuyuk et al. and Rhetinorhyssalites emersoni Engel et al. in Turonian amber from New Jersey; and Diorhyssalus allani (Brues), ‘Pygostylus’ patriarchicus Brues, and ‘Neoblacus’ facialis Brues in Campanian amber from Canada (
Parasitoid wasps of the family Braconidae remain a rarity in Cretaceous amber, despite the growing number of deposits with abundant arthropod inclusions (e.g.,
The authors thank two anonymous reviewers and Kees van Achterberg for their informative critiques which aided the improvement of the final paper. This project was supported by the International Scientific Partnership Program (ISPP) at King Saud University through ISPP #0083 (A.S.A. and M.S.E.), as well as by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB18030501), and the National Natural Science Foundation of China (91514302) (both to H.D.-Y.).