Aequitriradites sp. (Fig. 12E)

OCCURRENCE. — Ashikajima Fm.

DESCRIPTION

Zonate trilete microspore. Amb rounded subtriangular. Central body subcircular. Laesurae are not visible. Central body verrucate; verrucae are very small and contiguous (about 1-2 µm in diameter). The exine thickens near the periphery of the central body (about 3-3.5 µm). The zona is thin, granulate, radially folded, with irregular and more or less transparent margins. It is wider in three areas (about five times wider), which gives to the spore a subtriangular shape. No hilum is visible. Equatorial diameter = 45-70 µm; zona width = 2-12 µm.

BOTANICAL AFFINITIES

Bryophyta, Marchantiopsida.