Type analysis of Aulacoseira gessneri (Hustedt) Simonsen (Bacillariophyceae) from South America

Autor(es)

Wetzel, Carlos E. ; Ector, Luc ; Bicudo, Denise C.

• Tipo de documento: Artigo Científico
• Fonte: NOVA HEDWIGIA; v. N/A, p. 10-pg., 2014-01-01.

Resumo

Melosira gessneri, a colonial planktonic diatom, was first described from tropical South America (Tapajos River, Brazilian Amazon) and was later transferred to the genus Aulacoseira without detailed analysis of the type material. The species is reported in recent literature, mainly from pristine areas of Brazil like the Pantanal region and the Amazon basin in high abundances. Besides its occurrence in the type locality, Aulacoseira gessneri was reported in one sample from the lower reach of the Amazon River (Gurupa River) in the 1960's and more recently from the Pantanal region in central-western region of Brazil (La Plata basin). The objectives of this work are to analyse using light and scanning electron microscopy the type material described by Hustedt, as well as to verify the current distribution of the species. Confusion of this taxon with other common species such as A. muzzanensis and A. islandica are likely to be related to a poor knowledge of tropical South American planktonic diatom species. The presence of A. gessneri in large hydrographic basins such as distinct tributaries of the Amazon River and massive abundance records from the Pantanal region suggests that the species has been overlooked in other geographic areas and is probably more widely distributed in the South American continent. (AU)

• Processo FAPESP: 07/51360-6 - Biodiversidade e padrões de distribuição de diatomáceas (Ochrophyta: Bacillariophyceae) na Bacia Hidrográfica do Rio Negro, Amazonas, Brasil
• Beneficiário: Carlos Eduardo Wetzel
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto