Sellaphora tropicomadida sp nov., a new freshwater diatom species (Bacillariophyta) from a tropical Brazilian reservoir

Author(s)

Marquardt, Gisele C. ; Bicudo, Carlos E. de M. ; Ector, Luc ; Wetzel, Carlos E.

• Document type: Journal article
• Source: Rev. bras. Bot.; v. 40, n. 4, p. 12-pg., 2017-12-01.

Abstract

A new periphytic freshwater diatom species belonging to the genus Sellaphora Mereschkowsky has been recorded from a reservoir in Sao Paulo (Southeast Brazil) and is described as S. tropicomadida Marquardt and C.E. Wetzel, sp. nov. The new species most distinctive feature is the areolae internal ultrastructure, composed of large occlusions laid very close to the raphe, restricting an almost absent central area. Sellaphora madida (Kociolek) C.E. Wetzel in Wetzel et al. originally described from the USA. (Oregon) has been recently collected from locations different from the type locality and presents a disjunct distribution, with confirmed records in subtropical regions of South America (southern Brazil) and Europe (Bulgaria). These specimens were compared with those of S. tropicomadida sp. nov. to highlight the differences between them. All populations are illustrated in detail with light microscope (LM) and scanning electron microscope (SEM). Further comparisons of S. tropicomadida with similar species based on the literature and information about their ecology are also provided. We suggest careful examination of the small size dominant diatoms with SEM in routine monitoring, to get better results and increase taxonomic accuracy for ecological assessment, mainly concerning species with distinct ecological preferences, despite their morphological resemblance. (AU)

• FAPESP's process: 13/10314-2 - Comparison of biodiversity and distribution of planktonic diatoms, periphytic and surface sediments in six reservoirs in the southern state of São Paulo
• Grantee: Gisele Carolina Marquardt
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 09/53898-9 - Paleolimnological reconstruction of Guarapiranga Reservoir and diagnosis of water and sediment current quality of SPMR water supply reservoirs facing their management
• Grantee: Carlos Eduardo de Mattos Bicudo
• Support Opportunities: Research Projects - Thematic Grants