RESUMO
Non-indigenous bryozoans are frequent components of biofouling assemblages in harbour environments worldwide. We performed a survey of artificial hard substrates in six harbours spanning 16 degrees of latitude along the coast of Argentina, from Ingeniero White (38º47' S) to Ushuaia (54º48' S). Microeciella argentina n. sp., distributed in warm-temperate waters of northern Patagonia and Buenos Aires Province, is described. The non-indigenous species (NIS) Callopora dumerilii, Smittoidea spinigera and Stephanollona boreopacifica are recorded here for the first time in the Southwest Atlantic. Their occurrence in fouling assemblages of warm-temperate harbours and their previous absence in these areas suggest that they probably arrived in Argentina by international shipping traffic. Callopora dumerilii is native to Europe and the northeast Atlantic. Smittoidea spinigera and Stephanollona boreopacifica are native to China and Korea, respectively. The morphological differences between S. spinigera and the Californian species S. prolifera, which is invading European harbours in the North Sea, are discussed. Bugula neritina, Bugulina flabellata, Cryptosula pallasiana and Fenestrulina delicia, common in harbours of Buenos Aires Province, are here recorded in Patagonia, highlighting the importance of regional shipping traffic to secondary spread of NIS. Arachnidium fibrosum, Buskia socialis, Anguinella palmata, Aetea cultrata, Bicellariella edentata and Exochella moyanoi, previously known from Brazil, and Hippothoa divaricata, are here recorded in Argentina. This study shows that warm-temperate harbours in Buenos Aires Province and northern Patagonia are particularly prone to the introduction of non-indigenous bryozoans.
Assuntos
Briozoários , Animais , NaviosRESUMO
The family Calloporidae occupies a basal position in the classification of the Cheilostomata, the relatively simple calloporid morphology seeming to be the basic pattern for the adaptive radiation of cheilostome bryozoans. The ovicells of the Calloporidae may be formed by the maternal zooid or the distal zooid, which can be an autozooid, a vicarious avicularium or a kenozooid. Examination of new calloporid material from the southern Patagonian shelf revealed the existence of two new species and a new genus. Kenoaplousinafissurata gen. nov., sp. nov. is characterized by its distinctive kenozooidal ooecium. The new genus is also deemed to include Aplousina grandipora Moyano, an allied species from the Chilean continental slope. Alderina simplicissima sp. nov., is also described from the Magellanic region.