Feeding of Natirrica humeralis (Linnaeus, 1758) (Coleoptera: Mordellidae) on nectar from extrafloral nectaries of red elderberry (Sambucus racemosa L.)

Abstract

The article suggests that substances with a high sugar content, which are produced by plant secretory structures and are easily accessible to digestive enzymes, are of significant importance for tumbling flower beetles. The results of observations of feeding of Natirrica humeralis (Linnaeus, 1758) on nectar produced by extrafloral nectaries of red elderberry (Sambucus racemosa L.) are analyzed. The observation was carried out in July 2021 in the Baranovichi district of the Brest region (Belarus). The feeding of tumbling flower beetles on nectar from extrafloral nectaries is indicated for the first time. It is emphasized that red elderberry plants actively secreting nectar from extrafloral nectaries can be considered as one of the microstations occupied by the N. humeralis adults. The results obtained can be used to study microstationary ecological dispersion among tumbling flower beetles, especially considering the presence of a species morphologically and ecologically close to N. humeralis, such as Natirrica rufifrons (Schilsky, 1894). Photographs of the N. humeralis adult feeding on nectar from extrafloral nectaries of red elderberry, a general view of the plant, and weather conditions on the day of observation are given in the article. Brief data on the ecology of N. humeralis are also given. The dynamics of N. rufifrons distribution in Belarus in connection with climate change, which distinguishes this species from N. humeralis, is mentioned. A list of other insects attracted by the nectar of the extrafloral nectaries of this plant is also given. Rhagonycha fulva (Scopoli, 1763), Propylea quatuordecimpunctata (Linnaeus, 1758), Harmonia axyridis (Pallas, 1773) and also ants of the genus Myrmica belong to them. It is proposed to designate the scientific study of tumbling flower beetles as Mordellidology.