The distinction between Chondrophycus patentirameus and C. paniculatus (Ceramiales, Rhodophyta)

Abstract

The red algae Chondrophycus patentirameus (Montagne) Nam (‘patentiramea’) and L. paniculata (C. Agardh) J. Agardh were investigated on the basis of type material and recent collections. Both species show the following features: (i) production of two vegetative pericentral cells from each axial segment; (ii) absence of secondary pit connections between cortical cells; (iii) lack of projecting cortical cells near the apex; (iv) absence of lenticular thickenings in the walls of medullary cells; and (v) perpendicular arrangement of tetrasporangia, each of which is produced from the second pericentral cell in each fertile segment with no additional tetrasporangial pericentral cells. However, C. patentirameus has a stoloniferous holdfast, divaricate branching (with branches arising at angles up to 90°) and non-palisade-like superficial cortical cells, whereas L. paniculata has a discoid holdfast, non-divaricate branching and a palisade-like cortical layer. From this study it is concluded that C. patentirameus (here lectotypified) is distinct from L. paniculata. The latter species is here transferred to the genus Chondrophycus (Tokida & Saito) Garbary & T. Harper as follows: Chondrophycus paniculatus (C. Agardh) G. Furnari.