Achnanthes trachyderma (Meister) Riaux-Gobin, Compère, Hinz & Ector

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 : 24-25

32. Achnanthes trachyderma (Meister) Riaux-Gobin, Compère, Hinz & Ector ( Figs 75–77 )

Basionym: Cocconeis trachyderma Meister.

Type locality: ‘ Shell of a marine snail from Nagasaki’, Nagasaki, Japan .

Reference: Riaux-Gobin et al. 2015, p. 108, figs 19, 20, 27–29.

Morphometrics: Valves 33–37 (24–32) μm long, 16–18 (12–18) μm wide, transapical striae 8–11 (10–12) in 10 μm of sternum valve, and 21 (23–26) in 10 μm of raphe valve. Local specimens are a little larger than the type specimens.

Remarks: Achnanthes trachyderma was reported from a few regions, such as Tahiti and Moorea Islands of the southern Pacific Ocean ( Riaux-Gobin et al. 2015), and Rodrigues Island of the western Indian Ocean ( Al-Handal et al. 2016). It is a typical tropical taxon inhabiting warmer coasts. This taxon is rare epiphyte on seaweeds along the Seogwipo coast in Jeju Island, and is a new report to South Korea.

Figures

FIGURES 69–77. Diatom taxa of Seogwipo coast in Jeju Island (8). Figs 69–72. Hyalosynedra lanceolata. Figs 73, 74. Cocconeis heteroidea. Figs 75–77. Achnanthes trachyderma. Scale bars = 10 μm.