Geinitzia formosa Heer, 1871

Heřmanová, Zuzana, Kvaček, Jiří, Dašková, Jiřina & Halamski, Adam T., 2020, Plant reproductive structures and other mesofossils from Coniacian / Santonian of Lower Silesia, Poland, Palaeontologia Electronica (a 61) 23 (3), pp. 1-23 : 7-8

Geinitzia formosa Heer, 1871

Figure 3 D-F

v 1871 Geinitzia formosa Heer , p. 6, pl. 1, fig. 9, pl. 2,

figs. 1-6

v.1999 Geinitzia formosa Heer, Kunzmann , p. 114, pl.

26, figs. 1-8, pl. 27, figs. 1, 5-10, pl. 28, figs. 1-6 2003 Geinitzia formosa Heer, Kunzmann , p. 13, fig.

4A-D, pl. 4, figs. 1-9

Lectotype. No. UW 3936 , designated by Zijlstra et al. (2010), based on Kunzmann (1999), pl. 27, fig. 1, coll. University of Würzburg , Germany, Late Cretaceous, Santonian, Quedlinburg.

Description. Fragments of sterile twigs 1.0–2.0 mm broad, 4.0–13.0 mm long, with helically arranged needle-like leaves ( Figure 3D ), 1.5–4.5 mm long and 0.6–0.8 mm broad. Leaves triangular in cross section, showing a conspicuous keel ( Figure 3E ). Sometimes amber droplets preserved adhering to twigs. Abaxial cuticle shows two bands of stomata 200–500 µm broad ( Figure 3F ), the same arrangement is on abaxial cuticle. Stomata surrounded by 5–6 subsidiary cells. Stomatal axes irregularly orientated. Ledges of guard cells sunken in shallow stomatal chambers, sometimes surrounded by a slightly raised stomatal rim.

Remarks. We assign the studied material to Geinitzia formosa , as described from the type locality at Quedlinburg by Kunzmann (1999), particularly on account of leaves that are amphistomatic and triangular in cross section in terminal parts. G. formosa differs from G. reichenbachii in having shorter needles, which are frequently s-shaped. The needles of G. formosa are rhomboidal only in their basal parts, they are triangular terminally. G. formosa differs from Cunninghamites cf. squamosus , in having more three dimensional leaves. Leaves of Cunninghamites cf. squamosus are flattened in cross section, and their cuticle shows irregularly orientated stomata forming two bands. We also collected Seletya seeds in association, similarly to the situation described by Kunzmann (1999). However, Kunzmann did not make the nomenclatorial distinction between seeds and twigs, assigning seeds described herein under Seletya directly to Geinitzia (Kunzmann, 1999) along with sterile shoots.

Range. Late Coniacian or early Santonian age.

Occurrence. Żeliszów locality.

Material studied. NMP K 2933-5, 2942-6, 2947, 2955, 2958, 3009; the material is housed in the National Museum Prague.

Division ANGIOSPERMAE Brown and Doell ex Doell, 1857

Class Dicotyledoneae de Candolle, 1824

Order FAGALES Engler, 1892 s.l.

Genus CARYANTHUS Friis, 1983

Type species. Caryanthus knoblochii Friis, 1983, p. 172 , pl. 5, 6, 7, figs. 1-4

Remarks. Fruits of the genus Caryanthus are small, ribbed, bisymmetrical and epigynous, nuts supported by a bract showing single erect seed ( Friis, 1983; Friis et al., 2011, 2006; Heřmanová et al., 2016). In some cases, remains of perianth are preserved. They show a perianth consisting of four tepals arranged in two decussate pairs. The androecium is built of six to eight stamens. The gynoecium is bicarpellate, with a unilocular ovary and two free styles. Pollen is triaperturate and triangular in equatorial outline. A distinct Y-shaped mark extends between the apertures over the pole.

Figures

FIGURE 3. Conifers (A) Cunninghamites cf. squamosus terminal fragment of twig, no. K2948, scale bar 1 mm (B) Cunninghamites cf. squamosus isolated leaf with leaf cushion, no. K2956, scale bar 1 mm (C) Cunninghamites cf. squamosus adaxial cuticle showing two bands of stomata, no. K2956, scale bar 100 µm (D) Geinitzia formosa, fragment of twig, no. K2958a scale bar 1 mm (E) Geinitzia formosa, isolated leaf with keel, no. K2958b scale bar 1 mm (F) Geinitzia formosa, detail of abaxial cuticle showing two irregular stomatal bands, no. K2958b scale bar 100 µm (G) Alapaja sp. seed, no. K2962 scale bar 1 mm (H) Seletya sp. seed no. K 3012 scale bar 1 mm (I) Seletya sp. seed no. K 3013, scale bar 1 mm. All specimens from Żeliszów locality.