Field collection study documents Georgia’s first Ripiphoridae beetles

Field collections conducted in Georgia from 2021 to 2023 documented the country’s first recorded specimens of the beetle family Ripiphoridae. The collection included three species: Macrosiagon bimaculata, Ptilophorus dufouri and Ripiphorus subdipterus. The study reports collection localities, dates, habitats and photographs of the preserved specimens, establishing a new country record rather than a systematic inventory of the family.

The specimens were gathered during individual daytime forays to Gori and the vicinity of Tbilisi organized within the Caucasus Barcode of Life project. Collectors took the beetles by hand from the stems of weathered plants. The material was preserved in 96% ethanol and deposited in the ISU collection for subsequent genetic studies.

These collection details limit the work to targeted field encounters at three Georgian localities rather than a countrywide survey. Researchers identified the beetles using keys published by Iablokoff-Khnzorian and Batelka. Photographs of the preserved specimens were made with a Canon EOS 5D Mark II fitted with a Canon MP-E 65mm macro lens and a Canon Macro Twin Lite, with the system mounted on a Novoflex focusing rack.

Zerene Stacker and Adobe Photoshop CS6 were used to prepare the digital images. The reported material consisted of six specimens: three M. bimaculata, one R. subdipterus and two P. dufouri. Three female M. bimaculata were collected on 6 August 2022 in Shida Kartli near Gori, at 41.9811° N, 44.0921° E and 586 metres above sea level.

They were taken in a steppe locality associated with Eryngium. Earlier observations cited in the paper indicated that this species can occur on flowering Eryngium in July and August. M. bimaculata has a Western Palaearctic distribution and had been recorded in neighboring Armenia, Turkey and Ukraine, including Crimea, but not previously in Georgia.

The biology of M. bimaculata remains poorly understood. More generally, members of Macrosiagon are known to parasitize a broad range of wasps and bees. Within Ripiphorinae, eggs are laid on plant surfaces, and newly hatched first-instar larvae, or triungulins, attach to host wasps or bees and are carried to the host nest.

A study cited by the paper associated particular Macrosiagon species or species complexes with different bee or wasp groups. The Georgian specimens provide a geographical record and do not document parasitism, host use or development by M. bimaculata. A single male R. subdipterus was collected on 24 July 2021 in Dighomi Village, Tbilisi, at 41.7799° N, 44.7092° E and 657 metres above sea level.

It was found in shrubland dominated by Paliurus spina-christi on dried Achillea. The species had previously been recorded in neighboring Armenia and Azerbaijan. A historical observation cited in the study identifies the solitary bee Halictus sexcinctus as the host of its first-instar larva, and that bee is known to occur in Georgia.

The specimen record itself does not establish a new host association or show an interaction between the bee and beetle at the Tbilisi locality. Two female P. dufouri were collected on 27 April 2023 in Dighomi Village, Tbilisi, at 41.7781° N, 44.7003° E and 476 metres above sea level. The specimens were taken from twigs in shrubland dominated by Paliurus spina-christi.

This species, a member of Pelecotominae, had previously been reported from neighboring Armenia, Turkey and Ukraine, including Crimea, but not Georgia. Unlike most wedge-shaped beetles, its adults have mouthparts adapted for feeding on liquid food, although its feeding behavior has not been observed. The host of P. dufouri remains unknown.

Its larvae were long unknown, and their weakly sclerotized, very small bodies and simplified mouthparts suggest a parasitic lifestyle and consumption of liquid food, but the paper presents this as an inference rather than a directly observed behavior. Ripiphoridae larvae more broadly develop, at least partly, within other animals. Host preferences differ among subfamilies: Ripiphorinae typically target aculeate Hymenoptera, some Ripidiinae attack cockroach nymphs, and Pelecotominae species target beetle larvae.

The paper notes that approximately 60 species have been documented in the Palaearctic region. It also cautions that the absence of earlier Georgian finds does not necessarily indicate inadequate study of the country. Many wedge-shaped beetles are known to have short adult lifespans, leaving them available for collection and observation only during limited periods.

Because the reported sampling involved individual forays at a limited set of localities and dates, the observations demonstrate the presence of three species but do not establish the size or composition of Georgia’s Ripiphoridae fauna. The authors therefore leave the total number of species in Georgia undefined and expect further investigation to yield additional discoveries.

Subject of Research: First country records of three Ripiphoridae beetle species collected in Georgia in 2021–2023

Article Title: The first record of Ripiphoridae ( Coleoptera , Cucujiformia , Tenebrionoidea ) family in Georgia

Article References: Iskandarova, T., Japarashvili, S., Bulbulashvili, N., & Seropian, A. (2024). The first record of Ripiphoridae (Coleoptera, Cucujiformia, Tenebrionoidea) family in Georgia. Caucasiana, 3, 19-23. https://doi.org/10.3897/caucasiana.3.e115578

Image Credits: AI Generated

DOI: 10.3897/caucasiana.3.e115578

Keywords: Ripiphoridae, Georgia, beetles, Coleoptera, field collections, taxonomic records, Macrosiagon bimaculata, Ptilophorus dufouri, Ripiphorus subdipterus, Caucasus, first, record