Taxonomic review describes two new Episyron species and three new records for China

A specimen-based taxonomic review of Chinese spider wasps described two new species in the genus Episyron and documented three species as new records for China. The additions bring the country’s known inventory from three species and one subspecies to eight species and one subspecies. The new species are Episyron fulvimaculatus Song & Li and E. immaculatus Song & Ma.

E. fulvimaculatus was described from examined material collected in Yunnan, including Menghai County, Dehong State, Baoshan, Wenshan State and Yuxi. Females measured 9.2–13.5 mm in body length and 8.1–11.8 mm in fore-wing length; males measured 7.3–9.5 mm and 7.6–8.3 mm, respectively. E. fulvimaculatus has numerous fulvous markings, a largely fulvous mesosoma and tergites 4–6 that are almost entirely fulvous.

Its female first flagellomere measured 5.63–6.02 times its maximum width, while the male first flagellomere measured 1.42–1.64 times its maximum width. E. immaculatus was described from specimens collected at Helan Mountain in Inner Mongolia. Females measured 10.5–12.5 mm in body length and 8.1–9.8 mm in fore-wing length.

The name refers to the black metasoma, which lacks spots or bands. The authors distinguished it from E. rufipes using first-flagellomere proportions, postocellar and ocellocular distances, leg coloration, pterostigma shape and the absence of metasomal markings. The review also documented E. albonotatum, E. rufipes and E. rufotibius as new records for China.

Examined E. albonotatum and E. rufipes material came from Inner Mongolia, whereas examined E. rufotibius material came from Yunnan and Guangdong. The authors supplied descriptions, images and distribution information for these taxa. An illustrated key was provided for identifying Chinese Episyron species, with separate female and male pathways where males were known.

Diagnostic characters included body coloration and patterning, pterostigma form, fore-tarsal spines, antennal proportions, ocellar distances, wing structure and genital features. E. fulvimaculatus was compared with E. vagabundus hopponis using female first-flagellomere proportions, postocellar and ocellocular distances, pterostigma shape and the fore-metatarsal comb spine. This was a morphological examination of museum specimens rather than a field experiment.

Researchers used an Olympus SZ-series stereomicroscope with an ocular micrometer, photographed specimens using a Keyence VHX-5000 digital microscope system and edited the images in Adobe Photoshop 8.0. Wing-vein and cell terminology followed Day’s 1988 system. The occurrence records were based on examined material and cited reports, while broader geographic ranges were drawn from the literature.

The authors associated the expanded Chinese inventory with the country’s Palearctic and Oriental representation, extensive collection efforts, vegetation diversity, complex terrain and varied climatic conditions. These factors were presented as possible influences rather than experimentally tested causes of diversity. The revised Chinese total represented about 9% of the stated global inventory of 87 Episyron species and 13 subspecies.

Episyron species are small- to medium-sized predatory and parasitic wasps that prey on orb-weaver spiders. Previously cited biological research reported that females paralyze prey and move it to soil nests, while adults may visit flowers; these behaviors were not tested in the present morphological review.

Subject of Research: Taxonomic review of Chinese Episyron spider wasps

Article Title: Review and key of the Chinese species of the genus Episyron Schiødte ( Hymenoptera , Pompilidae ), including descriptions of two new species

Article References: Song, Z., Dong, L., Ma, L., & Li, Q. (2025). Review and key of the Chinese species of the genus Episyron Schiødte (Hymenoptera, Pompilidae), including descriptions of two new species. Deutsche Entomologische Zeitschrift, 72(2), 133-154. https://doi.org/10.3897/dez.72.138061

Image Credits: AI Generated

DOI: 10.3897/dez.72.138061

Keywords: Episyron, taxonomy, new species, China, spider wasps, Hymenoptera, Pompilidae, morphology, species identification, Review, Chinese, species