A Grammatical Dictionary of Botanical Latin

frondose: “leafy; frond-like or bearing fronds” (Fernald 1950); “leaf-like; resembling a fern frond, that is, with a distinct rhachis; in ferns, the frond is the stipe and lamina together; (in mosses) closely and regularly branched in one plane (pinnate); e.g. Thuidium; (in liverworts) a thallus that is crisped or lobed” (Magill 1990): frondosus,-a,-um (adj.A), q.v.; cf. ‘dendroid’ where branches radiate from the apex of a trunk or stipe; cf. foliaceous.

Frondose Ferns, or Club Mosses = Lycopodium (Paxton).

In liverworts, the vegetation may be divided into two groups: thallose and leafy liverworts. In older texts the thallose liverworts were called “frondose” and the leafy ones “foliaceous;” as by Sullivant (1856):

1. Vegetation frondose (stem and leaves confluent in a frond) [genera such as Marchantia, Metzgeria, Anthoceros]

2. Vegetation foliaceous (leaves and stem distinct) [genera such as Lophocolea, Jungermannia, Chiloscyphus].

In lichens: frondose thallus = “same as ‘foliaceous thallus’ (S&D).