Taxonomy and ecology of Achnanthidium (Bacillariophyta, Achnanthidiaceae) from southeastern Brazil with the description of six new species

Autor(es)

Costa, Livia F. ; Wetzel, Carlos E. ; Maquardt, Gisele C. ; Zanon, Jaques E. ; Ector, Luc ; Bicudo, Denise C.

• Tipo de documento: Artigo Científico
• Fonte: PHYTOTAXA; v. 575, n. 3, p. 37-pg., 2022-12-13.

Resumo

The present study aims to expand the knowledge on Achnanthidium species occurring in tropical areas of southern Brazil. For this purpose, 345 samples from 179 sampling sites distributed throughout the state of Sao Paulo were analyzed for 'monoraphid' diatom diversity. This paper focuses on samples with a high abundance of Achnanthidium species. The permanent slides and stubs were observed using light and scanning electron microscopy. Morphometric analysis was performed to discriminate between similar species through the Elliptical Fourier Descriptors analysis. For this, valve outlines from Brazilian species were compared to those from type material available from the literature. The ecological optimum and tolerance was calculated for taxa that presented more than 10 % of occurrence per habitat. In total, 12 Achnanthidium species were observed. Six are described as new: Achnanthidium acutum sp. nov., A. brasiliense sp. nov., A. parvicapitatum sp. nov., A. paulistanum sp. nov., A. ritae sp. nov. and A. vandevijveri sp. nov. The morphometric analysis supported the differentiation between some taxa. Nine species, with occurrences of at least 10 % per habitat, had their ecological optimum and tolerance calculated. In general, these species prefer slightly acidic to neutral pH, medium electrolyte cond. and mesotrophic water conditions. (AU)

• Processo FAPESP: 09/53898-9 - Reconstrução paleolimnológica da Represa Guarapiranga e diagnóstico da qualidade atual da água e dos sedimentos de mananciais da RMSP com vistas ao gerenciamento do abastecimento
• Beneficiário: Carlos Eduardo de Mattos Bicudo
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 17/04806-0 - Taxonomia e ecologia de Achnanthidium (Bacillariophyceae) no estado de São Paulo, Brasil
• Beneficiário: Lívia Franco da Costa
• Modalidade de apoio: Bolsas no Brasil - Doutorado