Mastogloiaceae Mereschkowsky

Al-Handal, Adil Y., Compère, Pierre & Criobe-Usr, Catherine Riaux-Gobin, 2016, Marine benthic diatoms in the coral reefs of Reunion and Rodrigues Islands, West Indian Ocean, Micronesica 2016 (3), pp. 1-78 : 14

Family Mastogloiaceae Mereschkowsky

Mastogloia affirmata (Leudiger-Fortmorel) Cleve (Pl. 14, Fig. 10) References: Hustedt 1931 -59, p. 528, fig. 962; Witkowski et al. (2000), p. 237, pl. 82, figs 2-4. Featurs: Apical axis: 34 µm, transapical axis: 14 µm, striae 12 in 10 µm.

Remarks: Only very few specimens were observed under SEM showing external valve face. This species however can be recognized by the strongly wavy raphe and the shape and arrangement of the areolae as well as the assymetric central area.

Occurrence: Rare in Rodrigues Island.

Mastogloia angulata Lewis (Pl. 5, Fig. 3) References: Hustedt 1931 -59, p. 465, fig. 885; Foged 1987, p. 56, pl. 11, figs 4-6; Witkowski et al. 2000, p. 238, pl. 80, figs 1, 2; Lobban et al. 2012, p. 266, pl. 23, figs 1, 2.

Features: Apical axis: 38-42 µm, transapical axis: 18-21 µm, striae 12-14 in 10 µm, areolae 16 in 10 µm. Partecta 6, with two large central ones, 2 in 10 µm, 3-4 µm wide.

Remarks: Stria density slightly higher than those reported in the bibliography (ca. 9-12 in 10 µm). Widespread species in the marine littoral of warm waters.

Occurrence: Frequent in Reunion and Rodrigues Islands.

Mastogloia binotata (Grunow) Cleve (Pl. 5, Fig. 13) References: Hustedt 1931 -59, p. 471, fig. 889; Witkowski et al. 2000, p. 240, pl. 75, figs 15-18; Lobban et al. 2012, p. 266, pl. 23, figs 3, 4.

Features: Apical axis: 18-22 µm, transapical axis: 14-18 µm, striae striae 13-15 in 10 µm, areolae 12 in 10 µm. Valves broadly elliptical. Raphe straight, central area distinct, variable in width and forming fascia extending to valve margin. Areolae hexagonal and appear in lines crossing each other. Valves with a single central partectum.

Remarks: M. binotata can be easily distinguished by the single elongated partectum which occupy almost a third of valve face. Widely distributed in warm waters.

Occurrence: Frequent in Reunion and Rodrigues Islands. Previously reported from Seychelles (G).

Mastogloia cf. citrus (Cleve) De Toni (Pl. 14, Fig. 11) References: Hustedt 1931 -59, p. 519, fig. 952; Wikowski et al. 2000, p. 241, pl. 78, figs 3, 4, 13, 14).

Features: Apical axis: 23-28 µm, transapical axis: 14-18 µm, striae 20 in 10 µm. Valves broadly elliptic with sub-rostrate rounded apices. Partecta rectangular and of the same size, 2.5 µm wide. Remarks: Specimens observed only showed internal side of the valve which is very similar to that of M. citrus .

Occurrence: Rare in Rodrigues Island.

Mastogloia corsicana Grunow (Pl. 5, Fig. 14) References: Hustedt 1931 -59, p. 454, fig. 966; Witkowski et al. 2000, pl. 77, figs 15-18; Lobban et al. 2012, p. 269, pl. 26, figs 1-3.

Features: Apical axis: 25-30 µm, transapical axis: 12-16 µm, striae 18-20 in 10 µm, partecta equal in size, 8-10 in 10 µm. Valves elliptical with rostrate apices. Raphe undulated, central area narrow and asymmetrical, axial area narrow. There are two to three longitudinal ribs interrupting the transapical striae. Partecta end shortly before valve poles.