The red algal genus Predeea (Nemastomataceae, Gigartinales) in Australia

Abstract

Abstract Four species of the genus Predaea from tropical and warm-temperate regions of eastern and western Australia are treated. Three of the taxa (P. incraspeda, P. huismanii, P. laciniosa) are newly described, while the fourth, P. weldii Kraft & Abbott, is recorded for the first time outside its Hawaiian type locality. Predaea incraspeda, from Lord Howe I., NSW, and P. huismanii, from Rottnest I., WA, are unique within the genus in displaying ‘shaggy’ outer cortices of exserted fascicles of unevenly long cortical filaments and in producing nutritive filaments on cells other than those immediately contiguous to the auxiliary cell. Predaea laciniosa, from the Great Barrier Reef, is one of the few Predaea species with compact submoniliform cortical filaments in which conspicuous intercalary gland cells occur. Predaea weldii appears to be widespread down the Australian east coast to the vicinity of 31° S lat. The earlier claim by Kraft and Abbott that P. weldii encompasses two distinct forms of greatly dif...