Syninclusions of the Eocene winter ant Prenolepis henschei (Hymenoptera: Formicidae) and Germaraphis aphids (Hemiptera: Eriosomatidae) in the Late Eocene Baltic and Rovno ambers: some implications

摘要

Prenolepis-Germaraphis syninclusions are reported for the first time from the Baltic and Rovno ambers. The number of syninclusions of those taxa in the representative Kalandyk collection of the Baltic amber (half of all samples with Prenolepis) indicates close lifetime relationship between Germaraphis and Prenolepis. We hypothesize that ants Prenolepis henschei were not dendrobiotic, i.e. they foraged on the resin-producing trees mainly looking for homopter-ans, particularly aphids which they did notkeep in their nests. The relationship between P. henschei and Germaraphis was not obligatory since it depended on the abundance of the aphids. Activity of the resin traps in the amber forests is supposed to be time-limited, and we hypothesize that the resin traps in the Baltic amber forest were active at lower temperatures if compared to the forests that produced the Scandinavian and Rovno ambers. This hypothesis explains the low proportion of workers and the high numbers of sexuals of P. henschei in the Scandinavian and Rovno ambers as compared to the Baltic one.