The genus Synarthrophyton (Corallinaceae, Rhodophyta) in southern Australia

Abstract

The genus Synarthrophyton (Corallinaceae, Rhodophyta) is represented in southern Australia by one species, S. patena (Hooker et Harvey in Harvey) Townsend. New data have shown that cell fusions vary in size and occur in both anticlinal and periclinal cell walls, and as a result can no longer be used to delimit Synarthrophyton from other genera of Melobesioideae. Male conceptacle development is described for the first time. Spermatangia are overlain by protective cells during early stages of development. Mature spermatangial branches may be either dendroid or both dendroid and simple. Growth-form is more varied than hitherto thought and includes specimens previously identified as Lithothamnion muelleri Lenormand ex Rosanoff. An updated description of Synarthrophyton is presented and the relationships of Synarthrophyton to other genera of the subfamily Melobesioideae are considered. New information is provided on host range, seasonal and geographic distribution in southern Australia.