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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.

We describe a sterile gametophyte fragment of a leafy liverwort preserved in Cretaceous amber from Myanmar, and place it in the extant genus Gackstroemia, as G. cretacea sp. nov., representing the second extant genus of leafy liverworts reported from the Mesozoic. The complicate bilobed leaves of the fossil have a ventral lobule forming a ciliately toothed, Frullania-type water sac, and a dorsal lobe carrying a single apical cilium, as well as bifurcate underleaves being either flat or developed as a pair of ciliately toothed water sacs. Gackstroemia cretacea is the first fossil record of Lepidolaenaceae, a family being at the present time confined to the southern temperate zone. The new fossil adds to growing evidence that southern disjunctions cannot exclusively be explained by Gondwanan vicariance and that the range of Lepidolaenaceae once included parts of Laurasia.

Examination of two pieces of amber from the mid-Cretaceous of Myanmar revealed seven inclusions of leafy liverworts that we assign to the extinct Frullania cretacea Hentschel et al. 2009. These inclusions show a suite of characters that were not visible in the type specimen of F. cretacea . The new gametophytes consistently display rectangular to ovate underleaves that have two long-ciliate apical teeth in addition to 0–2 blunt lateral teeth. A narrow stylus is present on at least some leaves. The lobules usually form water sacs that are 1.2–2.3 times longer than wide, and are arranged at some distance from the stem. The observed combination of character states is not present in extant crown group lineages of Frullania . A syninclusion in one of the amber pieces is interpreted as a detached gynoecium of a second Cretaceous Frullania species and is described as F. baerlocheri , sp. nov. The subgynoecial underleaves of the syninclusion are suborbicular in shape, and allow for a separation of this species from F. cretacea . The described amber inclusions are the oldest representatives of an extant genus of leafy liverworts known so far.

Mesozoic bryophyte fossils are rare and often assigned to form genera only. Here, we describe a fragment of a leafy liverwort preserved in Cenomanian amber from northern Alaska, and place it in a new genus, Kaolakia. The extinct species Kaolakia borealis resembles the extant Frullaniaceae in having perianths with a beak, as well as complicate-bilobed incubous leaves with a Frullania-type water sac; however, two water sacs are consistently present on each side of the stem. This character resembles Lepidolaenaceae and Goebeliellaceae, although the extant members of these families have coelocaules or truncate perianths. Thus our fossil likely represents an extinct lineage with affinities to Porellales, the primarily epiphytic clade of the leafy liverworts, and is possibly closely related to Frullaniaceae.