Alexandrium gaarderae Nguyen-Ngoc et Larsen

Hernández-Becerril, David U., Pichardo-Velarde, Jorge G., Alonso-Rodríguez, Rosalba, Maciel-Baltazar, Ebodio, Morquecho, Lourdes, Esqueda-Lara, Karina, Barón-Campis, Sofía A. & Quiroz-González, Nataly, 2023, Diversity and distribution of species of the planktonic dinoflagellate genus Alexandrium (Dinophyta) from the tropical and subtropical Mexican Pacific Ocean, Botanica Marina (Warsaw, Poland) 66 (6), pp. 539-557 : 542

3.1.2 Alexandrium gaarderae Nguyen-Ngoc et Larsen ( Figures 9–11 )

References: Nguyen and Larsen 2004, 90, pl. 6, figs 1–8; Menezes et al. 2018, 4.

Synonyms = Goniodoma concavum Gaarder , Gonyaulax concava (Gaarder) Balech , Alexandrium concavum (Gaarder) Balech.

Reference: Balech 1995, 60, pl. XVII, figs 24–29.

A very characteristic species with solitary and large cells, pentagonal in shape ( Figure 9 ). Epitheca irregularly conical with somewhat sinuous margins, hypotheca more rounded, flattened at the posterior margin, wide and excavated cingulum, and wide and deep sulcus ( Figures 9 and 10 ). Apical pore (Po) large and conspicuous ( Figure 11 ).

Measurements: 58–68 μm L, 48–55 μm W (Table 1).

Toxicity: this species is not considered to be toxic ( Long et al. 2021).

Distribution: in the Gulf of Tehuantepec.

Figures

Figures 9–11: Alexandrium gaarderae, LM. (9, 10) Two different focal planes of a solitary cell in ventral view, showing the cell outline, cingulum and sulcus. (11) A cell in dorsal view.