Distaltriangulisporites, Singh, 1971

Legrand, Julien, Pons, Denise, Nishida, Harufumi & Yamada, Toshihiro, 2011, Barremian palynofloras from the Ashikajima and Kimigahama formations (Choshi Group, Outer Zone of south-west Japan), Geodiversitas 33 (1), pp. 87-135 : 110-112

Incertae sedis sp. 1 ( Fig. 13N, O )

OCCURRENCE. — Ashikajima Fm.

DESCRIPTION

Microspore? Amb circular. The proximal face is not seen. The exine is reticulated with a mesh polygonal, of various shapes and sizes (lumina 1-5 µm in

diameter). The exine is about 1.5 µm thick. Equatorial diameter = 20-25 µm.

REMARKS

Only a group of these elements was observed, and isolated ones must be found to permit an observation of the two faces and propose an identification.

BOTANICAL AFFINITIES

Unknown.

Figures

FIG. 13. — Pollen grains, alga and fungus from the Barremian of south-west Japan: A, Pityosporites sp. cf. P. constrictus Singh, 1964, lateral view, Ashikajima Fm, II2b-J34/1; B, Alisporites thomasii (Couper, 1958) Pocock, 1962, polar view, Ashikajima Fm, II2b-O42/3; C, Incertae sedis sp. 2, Ashikajima Fm, II2c-W65/4; D, Balmeiopsis limbatus (Balme, 1957) Archangelsky, 1977, Ashikajima Fm, II2d- N41/2; E, Inaperturopollenites sp., Kimigahama Fm, I1b-U64/4; F-H, Classopollis torosus (Reissinger, 1950) Couper, 1958 emend. Burger, 1965 (F, distal polar view, Ashikajima Fm, SEM-II2a; G, distal polar view, Ashikajima Fm, II2c-H32/1; H, tetrad, Ashikajima Fm, SEM-II2a); I, Cycadopites minimus (Cookson, 1947) Pocock, 1970, Ashikajima Fm, II2e-U64; J, Cycadopites sp., Kimigahama Fm, I1a-X30; K, Ephedripites montanaensis Brenner, 1968, Ashikajima Fm, II2c-N35/4h; L, Gnetaceaepollenites sp., Ashikajima Fm, II2a-S47/1a; M, Corollina sp.,tetrad,Kimigahama Fm, I1a-X42; N, O, Incertae sedis sp. 1, group with detail,Ashikajima Fm,SEM-II2a; P, Pterospermella sp., Ashikajima Fm, II2b-O65; Q, Microthyriacites sp., Ashikajima Fm, II2e-R63/4. Scale bars: 10 μm.