Peltastaceae Kraft & G.W.Saunders, 2025

Peltastaceae Kraft & G.W.Saunders , fam. nov.

Type: Peltasta J.Agardh.

Thalli either multiaxial or uniaxial, terete to compressed, the medulla of narrow, darkly pigmented filaments or consisting of a single stout central-axial filament, each cell of which produces a single periaxial cell (rarely two) and cortical filament. Anchorage by basal haptera or stolons. Tetrasporangia zonate, basally pit-connected, scattered or in nemathecia. Thalli monecious, the spermatangia in ampullae sunken in the cortex or in cavities borne in extensive outgrowths from the cortex surface. Carpogonial branches three-celled, the auxiliary cell procarpic in the generitype ( Peltasta australis ), the gonimoblast initials and filaments radiating in all directions from a complex of the auxiliary cell and fused adjacent vegetative cells, deeply embedded beneath a down-growing ostiole and ultimately basally and interiorly placentate. Carposporangia borne singly on parallel filaments across the surface of the placenta.

Notes

This group of two genera sits as a well-delimited group next to members of the former Dicranemataceae assigned below to the new family Tylotaceae ( Fig. 8 View Fig ). Sister to the generitype of the family ( Peltasta australis ) is the new genus and species Peltastanomala virantra . The separate but deeply rooted, non-reproductive Chambersius thyrsus and Huismanophycus marinus have virtually no habit or anatomical features in common with the more distantly clustered Peltastaceae and Tylotaceae and are hence treated as incertae sedis until such time as cystocarpic features and molecular studies of additional, related taxa may better clarify the family affinities.