Morphology, anatomy and vegetative reproduction of Fosliella paschalis (Corallinaceae, Rhodophyta)

Abstract

The morphology, anatomy and vegetative reproduction have been examined in the holotype collection of Fosliella paschalis (Lemoine) Setchell & Gardner (Corallinaceae, Rhodophyta) and in new material of this species from the Canary Islands. All attributes characteristic of Fosliella Howe, with the exception of conspicuous spore germination discs, are present in the holotype. Morphologically, the type material is characterized by the coexistence of creeping filamentous thalli, minute suborbicular crustose thalli and larger crustose thalli. Loosely and closely coalescent hypothallial filaments occur in different thallus types. Sporangial conceptacles occur on minute orbicular thalli that develop on top of crustose thalli but are not in cellular connection with them. Vegetative propagules occur on some plants. In the Canary Islands plants, propagules arise from non-trichocytic, apparently unmodified hypothallial cells, and at maturity they form plano-convex discs that are attached by a unicellular stalk.