Tryblionella cf. jelineckii (Grunow) D.G.Mann Figs 107–110

Ref. illus.: Peragallo & Peragallo 1897 –1908 p. 268, pl. 69, fig 19, Hein et al. 2008, p. 84, pl. 58, fig. 19 (both as Nitzschia jelineckii Grunow); J.S. Park et al. 2022, p. 20, fig. 58.

Samples: GU52X-5

Dimensions: Length 121–158 µm, width 22 µm; striae 12–14 in 10 µm, fibulae 7 in 10 µm.

Diagnostics: Large panduriform species with prominent external costae running the width of the cell.

Comments: Similar to T. plana (W.Smith) Pelletan [Peragallo & Peragallo 1897 –1908 p. 270, pl. 70, fig. 18; Sims 1996, pl. 194, fig 2; Lopez-Fuerte et al. 2010, pl. 38, fig. 1 (all as Nitzschia plana W.Smith)], but that has 19–20 striae in 10 µm. Not clear from literature that either species has external costae. Montgomery (1978) has two images (pl. 160C and 161D) labeled as “ Nitzschia jelinecki ” but neither has external costae. Peragallo & Peragallo (1897 –1908) commented that they had only seen it in “exotic” samples, the one figured from Java; type was from the Nicobar Islands. This species needs much more study before we can say whether the Guam specimens belong in it or elsewhere.