Nodosisporites makotoi Legrand, Pons, Nishida & Yamada n. sp.

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 : 106

Nodosisporites makotoi Legrand, Pons, Nishida & Yamada n. sp. ( Fig. 10 A-F)

Nodosisporites sp., Legrand, Palynologie des dépôts Jurassique supérieur et Crétacé inférieur du Japon, et provinces paléofloristiques du sud-est asiatique: 166, 167, pl. XIII, figs 1, 2, 4, 7; pl. XIV, fig. 7 (2009).

TYPE MATERIAL. — Site II, horizon 2, slides a, b; holotype ( II2 a-L58/2; Fig. 10A, D ) ; paratypes ( II2 b-E56/3, II2b-U33; Fig. 10B, C, E, F ). Collection de Paléobotanique-UPMC, Paris, France.

ETYMOLOGY. — The species is named in honour of Prof. Makoto Nishida, who first studied fossil plants from the Choshi Group.

OCCURRENCE. — Ashikajima and Kimigahama formations.

TYPE LOCALITY. — Hatoyama, SE Choshi Peninsula, Chiba Prefecture, Japan.

STRATIGRAPHIC HORIZON. — Ashikajima Formation (Barremian).

DIAGNOSIS

Tetrahedral trilete microspore. Amb rounded triangular. Proximal face slightly flattened, with a psilate contact area followed by 1 or 2 muri parallel to the equator. The laesurae are relatively narrow, raised (about 3 µm), undulating, and extend to the 3/4 of the spore radius or to the equator; they are smooth or ornamented by small spines (0.5-1 µm high and 1-3 µm in basal diameter). Near the apices, 5-6 big spines (3-5 µm high) are present. A translucent equatorial zona with a dentate margin can be seen. The exine is cicatricose. The distal face shows 3 sets of 3-4 muri sinuous but parallel to the equator. One of these sets goes on to form a triangle (sometimes, more or less a network) centered on the distal pole ( Fig. 11 ). The ornamentation of this form corresponds to the type I-A defined by Krutzsch (1963). Equatorial diameter = 40-45 µm.

REMARKS

Appendicisporites dentimarginatus Brenner, 1963 shows similarities with Nodosisporites makotoi , but lacks spines on the apices.

BOTANICAL AFFINITIES

Schizaeales , Anemiaceae ( Dettmann & Clifford 1992) . The ornamentation shows similarities with that of Anemia phyllitidis (Linnaeus) Swartz from Brazil, figured by Tryon & Lugardon (1991).

Figures

FIG. 10.— Spores from the Barremian of south-west Japan:A-F, Nodosisporites makotoi n. sp.(A, D, proximal and distal faces,Ashikajima Fm, II2a-L58/2; B, E, proximal and distal faces, Ashikajima Fm, II2b-E56/3; C, F, proximal and distal faces, Ashikajima Fm, II2b-U33); G-K, Nodosisporites choshiensis n.sp.(G, H, lateral view,Ashikajima Fm,II2b-K22/2;I, lateral view,Ashikajima Fm,II2b-E40b;J, proximal face, Kimigahama Fm, SEM-I1a; K, distal face, Kimigahama Fm, SEM-I1b); L-N, Cingulatisporites sp. 1 (L, proximal face, Kimigahama Fm,I1b-R41;M, N, proximal and distal faces, Ashikajima Fm,II2c-J26/3);O, P, Cingulatisporites psilatus Groot & Penny,1960,proximal and distal faces, Kimigahama Fm, I1a-W67g; Q, Cingutriletes sp., proximal face, Ashikajima Fm, II2a-H67g. Scale bar: 10 μm.

FIG. 11. — Ornamentation of the schizaealean forms corresponding to new species or taxa placed in open nomenclature.