Pseudictyota reticulata (Roper) Sims & Williams

Joh, Gyeongje, 2021, Distribution and frequent occurrence of diatom taxa (Bacillariophyta) inhabiting warmer oceans in Seogwipo coast of Jeju Island, southernmost Korea, Phytotaxa 517 (1), pp. 1-67 : 16-18

19. Pseudictyota reticulata (Roper) Sims & Williams ( Figs 12, 18, 19 , 180, 181 )

Basionym: Biddulphia reticulata Roper.

Synonym: Triceratium dictyotum (Roper) Sims & Ross.

Syntype localities: Trincomalee , Sri Lanka ; Natal, South Africa; New Zealand .

Reference: Lobban et al. 2012, p. 250, pl. 6, figs 3, 4;

Morphometrics: Valves 69–122 (70–132) μm long, 40–66 (35–82) μm wide, and areolae 3–4 in 10 μm.

Remarks: Valves are bipolar, and rimoportulae with long external tubes near the base of the ocelli are characteristic of this taxon ( Lobban et al. 2012). Pseudictyota reticulata has been reported from some islands of the Pacific Ocean ( Ricard 1977, Foged 1987, Lobban et al 2012), and from the Caribbean Sea ( Navarro 1981), southern China and Taiwan ( Li 1978, Jin et al. 1985), in addition to Thursday Island of Queensland in Australia, New Hebrides, and Philippines ( Sims et al. 2018). Based on its distribution, it is considered as a taxon preferring warmer marine water. It is encountered frequently as an epiphyte on seaweeds in the Seogwipo coast, representing a new record for South Korea.

Figures

FIGURES 12–21. Diatom taxa of Seogwipo coast in Jeju Island (2). Figs 12, 18, 19. Pseudictyota reticulata. Figs 13–15. Biddulphia gruendleri. Figs 16, 17. Isthmia minima. Figs 20, 21. Biddulphia tridens. Scale bars = 10 μm.

FIGURES 176–184. Diatom taxa of Seogwipo coast in Jeju Island (18). Fig. 176. Auricula complexa. Fig. 177. A. flabelliformis. Figs 178, 179. A. intermedia. Figs 180, 181. Pseudictyota reticulata: external view of valves, and large ocellus and a rimoportula tube (Fig. 180). Figs 182, 183. P. dubium: internal (Fig. 182) and external view (Fig. 183) of valve. Figs 176–179: LM, Figs 180–184: SEM. Scale bars = 10 μm (Figs 176–179, 181, 183, 184), 5 μm (Fig. 182), 2 μm (180).