CECOAL   02625
CENTRO DE ECOLOGIA APLICADA DEL LITORAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Diversity of basic morphological unities of Xanthophyceae from Argentina
Autor/es:
PIZARRO, H.N., ZALOCAR DE DOMITROVIC, Y. & TELL, G.
Lugar:
Joao Pessoa, Brazil
Reunión:
Simposio; Plankton Symposium IV; 2007
Institución organizadora:
Universidade Federal of Paraíba
Resumen:
This work deals with the morphological diversity of coccoid Xanthophyceae from North East Argentina’s large wetlands. Phytoplankton from shallow lakes, lagoons, relictual oxbow lakes and other water bodies of humic characteristics was analysed from samples taken over 20 years. Microscopic algal species may be mainly classified following three concepts: morphological, biological and molecular species. It is not always possible to apply the three concepts together, and frequently taxonomist select only one technique. Due to the long period of sampling and the few individuals of each form found, only morphological studies are possible to apply in our samples. Moreover, sexual reproduction is unknown in coccoid Xanthophyceae, therefore biological methods are impossible to use. The term Basic Morphological Unities (BMU) for defining each one of the different observed morphological type is proposed. Only 18 from the 74 recognized BMU coincide with previously described taxa (genus Tetraedriella, Tetraplektron, Goniochloris, Isthmochloron and Psedostaurastrum). We consider that it is impossible to create new taxa for each one of these morphological type because the limits of the morphological variability are unknown. The value of the term BMU from the taxonomical and ecological point of view is discussed.