Fine-structural characterization and phylogeny of Sphaerodinium (Suessiales, Dinophyceae), with the description of an unusual type of freshwater dinoflagellate cyst.
Eur J Protistol
; 78: 125770, 2021 Apr.
Article
em En
| MEDLINE
| ID: mdl-33549968
ABSTRACT
Two strains of Sphaerodinium were established from two mountain areas in Portugal and examined by light microscopy, scanning and transmission electron microscopy, and sequence analyses of nuclear-encoded SSU, ITS1-5.8S-ITS2 and LSU rDNA. Both strains were identified as S. polonicum var. tatricum on the basis of comparison with the original taxonomic descriptions within the genus. The two strains were nearly identical in morphology and ultrastructure, except for the presence of pseudograna-like thylakoid stacks within more rounded chloroplast lobes in one of them. Sexual reproduction occurred in culture batches and resting cysts with single or grouped processes with wide bases and distal platforms with slightly recurved margins were seen to develop by sudden retraction of planozygote cytoplasm. Morphological, fine-structural and molecular characters were compared with previously available information from S. cracoviense, allowing for a more robust characterization of the genus. Important characters include a type F eyespot, a pusule canal linking the transverse flagellar canal to a collecting chamber connected to regular pusular tubes, a ventral fibre extending from the proximal-right side of the longitudinal basal body, and a membranous, lamellar body with a honeycomb pattern near the flagellar base area. The latter two features are shared with Baldinia anauniensis.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Filogenia
/
Dinoflagellida
Idioma:
En
Revista:
Eur J Protistol
Assunto da revista:
BIOLOGIA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Portugal