Document of bibliographic reference 339627

BibliographicReference record

Type

Bibliographic resource

Type of document

Journal article

BibLvlCode

AS

Title

Planothidium scrobiculatum sp. nov. (Bacillariophyta), a new monoraphid diatom from freshwater Pleistocene deposits of South America

Abstract

A new monoraphid diatom species appeared successively in paleolimnological records from a Quaternary sediment core (1.5±0.1 Ma) retrieved from Colônia basin (Brazilian Coastal Plain, Atlantic Forest, São Paulo Metropolitan Region), and is formally described as Planothidium scrobiculatum sp. nov. We studied the new species through light and scanning electron microscopy and discussed its similarity to other members of the genus. The new species has a unique combination of morphological features that allow its separation from all other species in the genus: (1) lanceolate valve outline with cuneate apices, (2) multiseriate striae composed of two to four rows of irregular sized areolae on the rapheless sternum valve (SV), not interrupted at the valve mantle junction, and (3) arrangement of areolae on the valve mantle, grouped in 3 or 4 rows, each composed of 2 to 3 areolae on the SV. Nevertheless, the new species main diagnostic feature is the occurrence of numerous, unusual, small shallow depressions externally located on the SV along the axial area, cavum, and virgae. As a result, P. scrobiculatum is different from similar species under LM and SEM by some evident characters or a combination of characters. This study contributes to the knowledge of the so far understudied biodiversity of microorganisms of tropical regions. In addition, the above-mentioned diversity patterns and the wealth of new diatom taxa inside and around the Colônia basin (many yet to be described) suggest that further samplings from other localities may provide an insight into its habitat preferences and range, since this area is an exceptional biological entity, worthy of further study.

WebOfScience code

https://www.webofscience.com/wos/woscc/full-record/WOS:000636787100006

Bibliographic citation

Marquardt, G.C.; Bicudo, D.C.; de Bicudo, C.E.M.; Ledru, M.-P.; Ector, L.; Wetzel, C.E. (2021). Planothidium scrobiculatum sp. nov. (Bacillariophyta), a new monoraphid diatom from freshwater Pleistocene deposits of South America. Fottea 21(1): 53-61. https://dx.doi.org/10.5507/fot.2020.016

Topic

Marine

Is peer reviewed

true

Access rights

open access

Is accessible for free

true