Studies on woloszynskioid dinoflagellates VI: description ofTovellia aveirensissp. nov. (Dinophyceae), a new species of Tovelliaceae with spiny cysts

Abstract

A new species of Tovellia, T. aveirensis, is described on the basis of light (LM) and scanning electron microscopy (SEM) of motile cells and resting cysts, complemented with transmission electron microscopy (TEM) of flagellate cells and phylogenetic analysis of partial sequences of the large subunit ribosomal rRNA gene. Both vegetative cells and several stages of a life cycle involving sexual reproduction and the production of resting cysts were examined in cultures established from a tank in the University of Aveiro campus. Vegetative cells were round and little compressed dorsoventrally; planozygotes were longer and had a proportionally larger epicone. Chloroplast lobes were shown by TEM to radiate from a central, branched pyrenoid, although this was difficult to ascertain in LM. The amphiesma of flagellate cells had mainly 5 or 6-sided vesicles with thin plates, arranged in 5-7 latitudinal series on the epicone, 3-5 on the hypocone. The cingulum had 2 rows of plates, the posterior row extending into the hypocone and crossed by a series of small projecting knobs along the lower edge of the cingulum. A line of narrow amphiesmal plates extended over the cell apex, from near the cingulum on the ventral side to the middle of the dorsal side of the epicone. Eight or 9 narrow amphiesmal plates lined each side of this apical line of plates (ALP). Resting cysts differed from any described before in having numerous long, tapering spines with branched tips distributed over most of the surface. Most mature cysts showed an equatorial constriction. Neither cysts nor motile cells were seen to accumulate red cytoplasmic bodies in any stage of the cultures. The phylogenetic analysis placed, with high statistical support, the new species within the genus Tovellia; it formed a clade, with moderate support, with T. sanguinea, a species notable for its reddening cells.

Morphology and phylogeny of a new woloszynskioid dinoflagellate Tovellia paldangensis sp. nov. (Dinophyceae)

“…In particular, T. paldangensis differs from T. apiculata, T. aveirensis and T. stoschii in terms of the plate series on the cell surface (von Stosch 1973;Shyam & Sarma 1975;Pandeirada et al 2014). T. apiculata, T. aveirensis and T. stoschii have many plate series in the cell surface.…”

“…At present, six species of Tovellia are known to have resting cysts. The cyst of each species has a constriction or paracingulum in the middle; some species have pre-and post-cingular rows of roundish protuberances and other species have straight or somewhat conical protuberances (Lindberg et al 2005;Pandeirada et al 2014). Five species have bipolar horns that extend from the apex and antapex, and one species has numerous branched processes.…”

“…The Tovelliaceae includes Tovellia, Esoptrodinium, and Jadwigia (Lindberg et al 2005;Moestrup et al 2006;Pandeirada et al 2014). The addition of T. paldangensis to the Tovelliaceae supports this as monophyletic group, with the genus Tovellia grouped with Esoptrodinium gemma.…”

Studies on Woloszynskioid Dinoflagellates X: Ultrastructure, Phylogeny and Colour Variation in Tovellia rubescens n. sp. (Dinophyceae)

“…The new species is the third species of Tovellia to be reported from continental Portugal (Pandeirada et al. , , ).…”

Studies on woloszynskioid dinoflagellates VII. Description ofBorghiella anderseniisp. nov.: light and electron microscopy and phylogeny based on LSU rDNA

“…Lindberg et al, 2005). The systematics and evolutionary history of these dinoflagellates have recently been examined in detail and they were shown to comprise a highly polyphyletic assemblage (Lindberg et al, 2005, Moestrup et al, 2006, 2009a, 2009b, Pandeirada et al, 2014. Hence, polygonal plates in latitudinal series have evolved multiple times during the evolution of dinoflagellate lineages, and this morphological feature should not be regarded as an indicator of relationships.…”