Zamites bayeri J. KVAČEK

Greguš, Josef & Kvaček, Jiří, 2015, Revision Of Cenomanian Flora From The Maletín Sandstone, Acta Musei Nationalis Pragae Series B 71 (3 - 4), pp. 315-364 : 320

cf. Zamites bayeri J. KVAČEK in KNOBLOCH et J. KVAČEK

Pl. 3, Fig. 2–7

1900 Podozamites latipennis HEER ; Bayer, p. 26, pl. 2, fig. 3.

1914 Podozamites latipennis HEER ; Bayer, p. 23, text-fig. 11.

1920 Podozamites latipennis HEER ; Bayer, p. 26, text-fig. 11.

1997 Zamites bayeri J. KVAČEK in KNOBLOCH et J. KVAČEK, p. 569, text-fig. 2a.

H o l o t y p e: NM-F2353, Knobloch and J. Kvaček

1997, p. 569, text-fig. 2a.

P a r a t y p e: NM-F2167, Knobloch and J. Kvaček 1997,

p. 569, text-fig. 2b.

T y p e l o c a l i t y: Praha-Malá Chuchle.

S t r a t i g r a p h y: Peruc-Korycany Formation, Cenomanian, Upper Cretaceous.

O c c u r r e n c e: Maletín, Velké Opatovice.

D e s c r i p t i o n. Studied specimens from Maletín are represented by four partially preserved, simply pinnate leaf impression, with rachis and several fragments of isolated leaflets. On approximately 5 mm wide rachis, there are leaflets arranged sub-alternately. The best preserved specimen, no. GBA_4 (Pl. 3, Fig. 2b) shows leaflets up to 165 mm long. Leaflets are lanceolate, up to 11 mm wide, and 5–10 mm apart. Their apex is rounded or slightly narrowing, frequently seemingly missing; base is slightly constricted (Pl. 3, Fig. 2a). Simple veins run parallel with leaflet margin; they are typically 2–3 per mm. Two poorly preserved specimens show pinnate leaves (GBA_134, Pl. 3, Fig. 5; MMT(M)/G_431, Pl. 3, Fig. 6), with leaflets typically constricted in basal parts. Despite the missing apex, leaflets are up to 90 mm long. Other specimens show fragments of leaflets up to 12 mm wide, with parallel venation. An isolated fragment of leaflet (MZM/118_18, Pl. 3, Fig. 4) and its negative MZM/118_23 show a preserved rounded to obtuse apex. Specimen no. GBA_66 (Pl. 3, Fig. 3) shows a well preserved base with typical basal constriction.

D i s c u s s i o n. Zamites bayeri is similar to Dioonites cretosus (REICH) SCHIMPER (= Pterophyllum saxonicum REICH ) from the Cenomanian of Saxony (Schimper 1870). In the Bohemian Cenomanian, this type of foliage was first discovered by Bayer (1900) in sandstones from Hořice. D. cretosus has folioles more regularly, densely arranged, with the base gradually narrowing and more decurrent ( Viniklář 1933). Distance between leaflets on the rachis is only 2 mm; for Z. bayeri it is up to 10 mm. Leaflets of C. cretosus are 15–20 mm wide, showing only 11–13 veins, while leaflets of Z. bayeri are 10–12 mm wide and show 30–36 veins. Zamites cf. bayeri is known from the locality Velké Opatovice (Knobloch and J. Kvaček 1997), which is close to the locality Maletín. Also, this specimen lacks anatomical evidence, and its determination is based only on morphological characters.

Specimen no. GBA_5 (Pl. 3, Fig. 7) is rather different from the rest of the material, having decurrent bases of leaflets. Based on this character, we assign this specimen to cf. Zamites bayeri with question mark.