Mastogloia affirmata (Leuduger-Fortmorel) Cleve Figs 49, 50

Section: Undulatae

Ref. illus.: Hustedt 1931 –1959, fig. 962.

Samples: GU44AX-1

Dimensions: Length 39 µm; width 22 µm; transapical striae 14 in 10 µm, longitudinal striae 10 in 10 µm except for the wider row adjacent to axial area; partecta 3.3 µm wide, 13 in 10 µm.

Diagnostics: Coarsely areolate, those along the raphe notably elongated; apices produced; longitudinal ribs almost straight; partectae very narrowly rectangular.

Comments: Distinguished from the very similar M. bahamensis Cleve (Hustedt 1931 –1957, fig 963, Hein et al. 2008, pl. 34, fig. 6 and pl. 36, fig. 10), which has irregularly wavy longitudinal ribs, according to Hustedt, and from M. subaffirmata Hustedt (see below) by the much coarser striae. Record based on a single specimen from Guam, but also seen in samples from Yap (unpublished).