Abstract
Kikuchi N. and Shin J.-A. 2011. Porphyrostromium japonicum (Tokida) Kikuchi comb. nov. (Erythropeltidales, Rhodophyta) from Japan. Phycologia 50: 122–131. DOI: 10.2216/10-06.1
The morphology and life history of Erythrotrichia japonica Tokida (Erythropeltidales, Rhodophyta) from Japan have been investigated, and its taxonomic placement is discussed. The monospores released from the field-collected erect foliose thalli grew into discoid bases that produced many erect foliose thalli similar to field thalli within 3 d. Vegetative cells of the middle to upper portion of erect thalli divided into two unequal cells, and the smaller pale cell was released as a spermatium at 15–20°C. Spermatia attached to cells of foliose thalli allowing for fertilisation. Presumed zygotes were formed and divided, releasing a cell that grew into a discoid thallus. Discoid thalli grew and released monospores. The monospores grew into additional discoid thalli. At 15–25°C under 10L∶14D, a few erect branches were produced from central parts of discoid thalli. Monospores from the erect branches grew into foliose thalli with a small base. Porphyrostromium japonicum (Tokida) Kikuchi comb. nov. was proposed based on this morphology and life history.
ACKNOWLEDGEMENTS
We are grateful to Prof. John A. West, University of Melbourne, for his critical reading of the manuscript and helpful suggestions and Prof. Michael J. Wynne, University of Michigan Herbarium, for his kind advice on the treatment of the type. We also thank Drs K. Kogame and T. Abe, Hokkaido University, for allowing us to examine specimens deposited in TI herb. Yendo in SAP and Dr H. Yasui, Hokkaido University, for allowing us to examine specimens deposited in herb. Tokida in HAK.