A new species of acorn barnacle, Actinobalanus? sloveniensis, is recorded from Oligocene and Miocene deposits in Slovenia, representing the first record of extinct balanoids attached to plant remains from this country, and in fact from the entire central Paratethys. Assemblages available include more than 200 specimens attached to tree branches and/or roots from a cypress forest (Tavodioxylon) and from estuarine mangroves (Carapoxylon).
A taphonomic interpretation is provided, suggesting that some of these remains represent fragments that were dislodged during a storm event and quickly embedded in what were likely to have been anoxic sediments.