Diversity and distribution of species of the planktonic dinoflagellate genus Alexandrium (Dinophyta) from the tropical and subtropical Mexican Pacific Ocean Author Hernández-Becerril, David U. Author Pichardo-Velarde, Jorge G. Author Alonso-Rodríguez, Rosalba Author Maciel-Baltazar, Ebodio Author Morquecho, Lourdes Author Esqueda-Lara, Karina Author Barón-Campis, Sofía A. Author Quiroz-González, Nataly text Botanica Marina 2023 Warsaw, Poland 2023-11-06 66 6 539 557 http://dx.doi.org/10.1515/bot-2023-0037 journal article 10.1515/bot-2023-0037 1437-4323 11000291 3.1.5 Alexandrium margale fi i Balech ( Figures 22–24 ) References: Hallegraeff et al. 1991 , 580, figs 10–16; Balech 1994 , 220, figs 12–15; Balech 1995 , 78, pl. XVI, figs 19–32; Hallegraeff et al. 2010 , 186, figs 4.18F, 4.19D. Figures 22–24: Alexandrium margale fi i , LM.(22) General outline of a cell. (23) An empty cell in ventral view showing 1′ and 6″ and the ventral pore (arrow) in the first apical plate (1′). (24) Hypotheca with plate tabulation. Solitary cells of medium-size, subspherical shaped, longer than wide ( Figure 22 ). The epitheca is convex ( Figure 23 ), wide and excavated cingulum, and the hypotheca is convex ( Figure 24 ). The first apical plate (1′) is not connected with Po, is quadrilateral and has a small ventral pore on its upper margin ( Figure 23 ). The posterior sulcal plate (Sp) has an oblique anterior border. Measurements: 26–36 μm L, 26–35 μm W (Table 1). Toxicity: this species is not considered to be toxic ( Long et al. 2021 ). Distribution: in the middle of the Gulf of California .