Protoperidinium pallidum (Ostenfeld) Balech 1973

Krakhmalnyi, Aleksandr F., Krakhmalnyi, Maxim A., Terenko, Galyna V. & Goncharenko, Igor V., 2023, Dominant Species Of The Genus Protoperidinium Bergh (Peridiniales: Protoperidiniaceae) In The Black Sea, Zootaxa 5339 (5), pp. 427-448 : 439

Protoperidinium pallidum (Ostenfeld) Balech 1973 . Revta Mus. Argent. Cienc Nat. “ B. Rivadavia ”, Hidrobiol. 3 (5): 365, pl. 6, Figs. 101–110. ( Figs. 35–43 ) .

References: Lebour 1925: 134, Pl. XXVIII, Fig. 1 a–d ; Schiller 1937: 209, Fig. 206 a–m; Kiselew 1950: 188, Fig. 313 a–v; Wood 1968: 106, Fig. 318 (as Peridinium pallidum ); Krakhmalnyi 2011: 203, Table 85: 1–15.

Basionym: Peridinium pallidum Ostenfeld 1899 . Plankton i 1898, Jagttagelser etc., Kbhvn.: 60.

Description: Cells rhomboid or pentagonal, slightly dorsally compressed, with straight lateral sides. The apical pore structure of Bʹ– type ( Toriumi & Dodge 1993). The epithecal plate pattern comprises seven precingular plates (7ʹʹ), four apical plates (4ʹ), three anterior intercalary plates (3a), 1ʹ plate – “para”, 2a – “hexa”. The thecal surface reticulated. The cingulum median, ascending (displaced by 1.0 cingular width), bordered. The hypotheca with two short slightly divergent antapical spines. The plate 1ʹʹʹ bears the hypothecal pore ( Abé 1981; Dodge 1987; Okolodkov 2003). The sulcus broad, expanding, left sulcal list larger, protruding at the base of the left antapical spine. The cells contents pink. Dimensions: 51.1–96.7 μm long and 33.0–88.9 μm wide.

Distribution: Coastal and oceanic from cold temperate to warm temperate waters; worldwide distribution ( Steidinger & Tangen 1997). Data on the distribution of P. pallidum are given from the GBIF.org (2022) ( Fig. 91 ).

Figures

FIGURES 35–46. Protoperidinium of the Black Sea. 35–43—P. pallidum; 44–46—P. leonis. Designations: 1ʹ—first apical plate, 2a—second intercalary plate. Hypothecal pore in plate 1ʹʹʹ is marked with an arrow (35, 36, 38). 38–40—DIC; 35–37, 45—epifluorescence; 41–43—FE-SEM; 44, 46—transmitted light. Scale bars: 20 µm.

FIGURES 1–10. Protoperidinium of the Black Sea. 1–2—P. achromaticum; 3–4, 7—P. brevipes; 5, 10—P. quadrioblongum; 6, 8–9—P. excentricum. Designations: 1ʹ—first apical plate, 2a—second intercalary plate. 4, 6–9—epifluorescence; 5, 10— transmitted light. Scale bars: 10 µm.

FIGURES 86–94. Global distribution maps of some Protoperidinium species. 86—P. excentricum; 87—P. granii; 88—P. knipowitschii (Krakhmalnyi, 2011); 89—P. leonis; 90—P. mediterraneum; 91—P. pallidum; 92—P. pellucidum; 93—P. pentagonum; 94—P. pyriforme.