The marine Acrochaetiaceae (Rhodophyta) of southern Africa

An investigation of the hitherto little explored red algal family Acrochaetiaceae on the southern African coast has yielded a total of 20 species so far. They are representatives of the genera Acrochaetium (7 species), Audouinella (6 species), Colaconema (6 species) and Rhodothamniella (1 species). Of these, 4 species are described as new to science, viz., Acrochaetium hlulekaense n. sp., Audouinella balliae n. sp., Audouinella occulta n. sp. and Colaconema monorhiza n. sp. Descriptions and illustrations of all species are given, primarily based on field-collected material, but often completed from observations on culture-obtained material. It appears that, broadly speaking, the genera Acrochaetium, Colaconema and Rhodothamniella are found in the lower eulittoral and in the sublittoral fringe, whereas most Audouinella species occupy deeper sublittoral sites. With the exception of the epilithic Rhodothamniella floridula, all species usually grow on plant and animal substrates, with quite a number of them (semi-)endophytic or (semi-)endozoic. Apart from the newly described species, the western Cape acrochaetioid flora has many similarities with other temperate floras throughout the world, notably western Europe, while the Transkeian acrochaetioid flora is transitional between the temperate and known tropical/ subtropical types. S. Afr. J. Bot. 1985, 51: 291–330 ‘n Ondersoek is gedoen na die tot dusver weinig bestudeerde rooiwierfamilie Acrochaetiaceae aan die kus van suidelike Afrika, ‘n Totaal van 20 spesies is gevind, met verteenwoor-digers van die genera Acrochaetium (7 spesies), Audouinella (6 spesies), Colaconema (6 spesies) en Rhodothamniella (1 spesie). Hiervan word 4 spesies as nuut vir die wetenskap beskryf: Acrochaetium hlulekaense n. sp., Audouinella balliae n. sp., Audouinella occulta n. sp. en Colaconema monorhiza n. sp. Beskrywinge en illustrasies van al die spesies word gegee, in die eerste plek gebaseer op veldmateriaal, maar dikwels aangevul met waarneminge aan gekweekte materiaal. In die algemeen word spesies van die genera Acrochaetium, Colaconema en Rhodothamniella in die laer getysone en in die boonste sublitoraal-sone gevind, terwyl Audouinella-spesies in dieper water voorkom. Met uitsondering van die epilitiese Rhodothamniella floridula, groei die spesies ge-woonlik op ander plante en diere, terwyl sommige (half)endo-fities of (half)endosoies is. Die Wes-Kaapse Acrochaetiaceae (met uitsondering van die nuutbeskrywe spesies) vertoon, wat spesiesamestelling betref, baie ooreenkoms met die floras van ander gematigde streke in die wêreld, merkbaar met dié van Wes-Europa. Die Transkeise flora vertoon ‘n oorgangstipe tussen die gematigde en tropiese/subtropiese flora. S.-Afr. Tydskr. Plantk. 1985, 51: 291–330