An in situ preserved moss community in Eocene Baltic amber

We describe a bryophyte community in a piece of Eocene Baltic amber housed in the American Museum of Natural History in New York. Five gametophytic plant fragments with zig-zagged stems, rounded-obtuse, bordered leaves with shortly and narrowly decurrent bases, non-mamillose, rhomboidal or elongate-hexagonal cells and a single costa are described as Rhizomnium dentatum, sp. nov., differing from extant species by some leaves with shortly-dentate margins. Syninclusions are Pyrrhobryum sp. and a pleurocarpous moss of the order Hypnales. The ecology of the extant representatives of these taxa and the presence of a chilopod suggest that the preserved bryophyte community grew in short distance to the amber-procucing tree or on its root plate, rather than epiphytically.