Tryblionella hyalina, T.Ohtsuka, 2005

Im, Ari & Park, Jong Seong Khim and Jinsoon, 2020, Taxonomy and distribution of two small Tryblionella (Bacillariophyceae) species from the Northeast Asian tidal flats, Journal of Species Research 9 (3), pp. 191-197 : 194-195

Tryblionella hyalina

(Amossé) Ohtsuka 2005 ( Figs. 3, 4 )

Reference. Amossé 1924, p. 165, fig. 1.

Description. Valves are broadly lanceolate with acute apices, length 13.3 - 38.6 μm, width 7.3 - 13.3 μm. Fibu- la is extremely eccentric to the valve margin, indistinct. Valve face has a broad hyaline area along the apical axis. Striae are composed of distinct coarse puncta, irregularly scattered at the margin, 7 - 9 in 10 μm.

Taxonomic remarks. Tryblionella hyalina is similar to Nitzschia navicularis (Brébisson) Grunow , which also exhibits punctate areolae as well as transapical hyaline area. However the former has monoseriate striae yet the striae of N. navicularis are biseriate. In addition, T. hyalina is a marine species while N. navicularis is a freshwater species. For example, Choi (1988) has reported N. navicularis from the Songdo tidal flats in Korea, however the species should be identified as N. granulata var. hyalina considering its monoseriate striae.

a b c d e g h i f

Distribution. T. hyalina has been recorded from the mudflats of China ( Jin et al., 1985; Jin et al., 1991) and Japan (Ohstuka, 2005; Park et al., 2012a). In the present study, this species was observed from the Buno tidal flat of Ganghwa Island (2006, October), Oji tidal flat of Garorim Bay (2007, June), and Manpung tidal flat of Hampyeong Bay (2005, May). In the present study T. hyalina was observed from four locations along the Chinese coast of the Yellow Sea ( Fig. 1 ).

Figures

Fig. 4. Scanning electron microscope photographs of two newly recorded species. (a-d) Tryblionella adducta (a: external view of the whole valve, b: external view of the valve apex with slightly radiating striae, c: internal view of the whole valve, d: internal valve of valve apex with conspicuous fibulae); (e, f) Tryblionella hyalina (e: internal view of the whole valve, f: internal view of valve apex).

Fig. 1. Map showing the sampling locations along the coasts of the Yellow Sea where Tryblionella adducta and T. hyalina were observed.