Biddulphia gruendleri A. Schmidt

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 : 9

4. Biddulphia gruendleri A. Schmidt ( Figs 13–15 )

Synonym: Biddulphia pulchella var. grundleri (A. Schmidt) Cleve.

Type locality: Yokohama.

References: Schmidt 1888, pl. 118, figs 22–24; Skvortzow 1932. p. 152, pl. 1, fig. 11, pl. 2, figs 2, 3; Jin et al. 1985, p. 57, pl. 15, figs 109–111.

Morphometrics: Valves 72–117 (52–244) μm long, 44–51 μm wide, girdle view 72–117 (66–84) μm high, transapical striae 3–4 (3–4) in 10 μm.

Remarks: Valves are strongly elevated with a hump in the middle, and transverse grooves are deep on the central hump bilaterally. Compared to its nominate variety, Biddulphia pulchella Gray , it is distinguished from the deep grooves and by the presence of two instead of four or more ribs.

This taxon was reported from the type locality, Yokohama of Japan ( Schmidt 1888), from the coasts of Fuzhou and Xiamen of Fujian province, China ( Skvortzow 1932, Jin et al. 1985), and from the western coast of the Baja California Peninsula, Mexico ( Siqueiros-Beltrones et al. 2016). According to Skvortzow (1932), it is distributed in the Sea of Japan, China, Philippines and the Adriatic Sea. However, the nominate variety, Biddulphia pulchella , differs in terms of widespread distribution in the temperate coasts as well as in tropical regions. It occurred infrequently with Biddulphia biddulphiana (J.E. Smith) Boyer as an epiphyte along the Seogwipo coast in Jeju Island. This taxon was reported the East Sea (the Sea of Japan) ( Skvortzow 1932), but was not found in Korean waters, and is new to 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.