M. Masuda et K. Kogame, AHNFELTIOPSIS TRIQUETRIFOLIA SP. NOV. (GIGARTINALES, RHODOPHYTA) FROMJAPAN, European journal of phycology, 33(2), 1998, pp. 139-147
The marine red alga Ahnfeltiopsis friquetrifolia sp. nov. (Phyllophora
ceae, Gigartinales) is described from Japan. Foliaceous unisexual game
tophytes are characterized by having three-edged axes, and crustose te
trasporophytes are distinguished by the following combination of featu
res: tightly coalescent perithallial filaments, nemathecial sori, smal
l numbers of both tetrasporangia (3 or 4) and sterile cap cells (1 or
2) in each fertile filament, and the absence of hypobasal tissue. Goni
moblast filaments develop from the auxiliary cell after it has fused w
ith a carpogonium. Carposporangia develop from gonimoblast cells, from
medullary cells contacted by the gonimoblast filaments, and from the
cells produced by such medullary cells. Mature, compact cystocarps are
immersed within the medullary layer and discharge carpospores through
carpostomes formed in the thickened cortex. Cultured tetrasporophytes
were induced to sporulate by transfer from a long-day to a short-day
regime at 20 degrees C, and one single short-day cycle was effective f
or tetrasporangial induction. Tetraspore germlings gave rise to basal
discs from which upright axes developed. The upright axes showed a mor
phology similar to that of field-collected gametophytes, although they
remained vegetative during 18 months in culture.