A fungal gall of Catenella nipae (Caulacanthaceae, Rhodophyta) and a review of Catenellocolax leeuwenii

Growths were found on the surface of Catenella nipae at Patonga, New South Wales, Australia. Morphologically similar growths on C. impudica from Indonesia have been reported as the red algal parasite Catenellocolax leeuwenii. The internal anatomy of the Australian growths showed that they all contained septate fungal hyphae. The hyphae formed spherical clusters that, in larger galls, produced inwardly directed hyphae terminating in spores. It is proposed in this paper that these galls are caused by fungal infection, as is the case in other algae. The lack of sexual structures precludes identification of this fungus to any definite species, although it is probably an ascomycete. Inspection of the type material of C. leeuwenii did not reveal any parasites. The limited description of the parasite of C. impudica, the proposed growths induced by fungi in C. nipae, and the lack of holotype specimens, warrants treating the generic name Catenellocolax with caution until more collections from the type locality can be made.