Prehistoric nests of Mud Dauber Wasps (Hymenoptera: Sphecidae) discovered in Transylvania, Romania

Fragments of mud dauber wasp’s nests dating from the Bronze Age (Noua culture, about 1500–1200 BC) from a Romanian archaeological site are described. The present discovery represents, to our knowledge, the first reported fragments of mud dauber nests recuperated from an archaeological site in Romania and probably among the rare ones from Europe. The archaeological site called Zoltan-“Nisipărie” is placed in the Covasna County, south-eastern Transylvania. The five fragments belong to two nests made by Sceliphron sp. wasps genus and they were described in terms of general and detailed morphology and morphometry. Two nest fragments preserve in situ secondary cells, showing evidence of nest reoccupation by other insects. Another important aspect of this discovery is the opportunity to extract and analyse a whole secondary cell from the original nest fragment. Various impressions of vegetal material (grass, straws etc.) and a seed on the nest fragments’ surface were observed using microscopic techniques. The preserved pieces recovered from archaeological investigations provide important data regarding the local environmental conditions during the recent period of Bronze Age in an anthropized environment of the Noua culture.

OM, SEM-EDX, and micro-FTIR analysis of the Bronze Age pottery from the Băile Figa salt production site (Transylvania, Romania)

This article presents the results of analyses carried out on a lot of 11 fragments of Bronze Age ceramics discovered in the site from Băile Figa (Beclean town, Transylvania, Romania), where salt exploitation occurred. The samples were analyzed by means of optical microscopy, on the basis of which the morphology and distribution of the inclusions in the ceramic paste was established. Likewise, the samples were analyzed by scanning electron microscopy with energy-dispersive X-ray spectrometry, producing microphotographs for each sample, and on the basis of the X-ray spectra, the elemental composition in gravimetric percentages was established. Through the micro-Fourier-transform infrared spectroscopy analysis, on the basis of characteristic group vibrations, it was possible to ascertain the nature of the compounds from the ceramic samples. These analyses will contribute to the reconstruction of the prehistoric technologies for salt exploitation.