Morphological studies of members of the tribe Agardhielleae (Solieriaceae, Rhodophyta)

Abstract

Abstract Sarcodiotheca furcata and S. dichotoma grow multiaxially with a single periaxial cell cut off from each succeeding axial cell in an orthostichous file. Branching of primary apices is dichotomous, apparently resulting from division of the apical cells into two equal initials, whereas lateral branches are formed adventitiously from surface cortical cells. The auxiliary cell complex, consisting of the auxiliary cell and surrounding darkly-staining inner cortical cells, is recognizable prior to diploidization. Typically, two unbranched and non-septate connecting filaments are formed from each fertilized carpogonium. Fusion of a connecting filament with an auxiliary cell stimulates development of the involucre. A gonimoblast initial is cut off from the auxiliary cell and divides forming a compact cluster of gonimoblast cells. In the first phase of carposporophyte development the gonimoblast radiates out and fusions occur between gonimoblast and vegetative cells producing a central placenta. In the sec...