Folia Historico-Naturalia Musei Matraensis - A Mátra Múzeum Természetrajzi Közleményei 17. (1992)

Bužek, Č.–László, J.: Contribution to the Upper Pannonian flora from Visonta, northern Hungary

CYPERACEAE Carex sp. (PI. IX, Figs. 1-4): Description: Utricles, thin, rather elongated, more than 6 mm long and about 2 mm wide with many longitudinal strise (vascular bundles), gradually narrowed to the base, stalked; a few utricles show nut inside nuts are small, regularly spindle-like, with rather long (incomplete) style, triangular. long-stalked (stalk incompletely preserved), about 2 mm long (with cut stalk and style) and 1.5 mm wide; surfece with very fine pits arranged longitudinally. Remark: We have been unable to identify this material with any extant or fossil species of Carex. Material: 5 utriculi with nuts, 4 isolated nuts, 3 incomplete utriculi and their fragments. Inventorized under Nos BK-5460, BK-5483, BK-5529 ZINGIBERACEAE Spirematospermum wetzleri (HEER) CHANDLER (PI. VIII, Fig. 11): Description: 5 to 8 cm long, 1.2 to 1.8 cm wide capsular fruit, with elongated, oval shape with the bottom and attenuated into a stem, and the top part rounded. On the edges blunt ribs are found which become smooth when reaching the stem . In longitudinal direction a fine fibrous arrangement can be observed on the external surface. The light setting of aligned seeds can be observed in the form of undulations and elevations visible on the capsule surface. Fruit finds were rather frequently damaged when embedded. Seeds are 0.9 to 1 cm long, 3 to 4 mm wide, dark brown and have bright seed-coat. The bottom part ends with an oval germgate with a diameter of 0.5 mm, whereas the upper part ends with a spiked tip. They are characterized by a twisting of 45 along the longitudinal axis, which represents a mark excellent for identification. Remark: The seeds with characteristic surface structure are rathnr common in the Pontian of southern Moravia (BUZEK 1962). From the Visonta region (Thorez, Keleti and Nyugati mines) they were already described by LÁSZLÓ 1991b). Material: 5 seeds. Inventorized under Nos BK-5477, BK-5510 ECOLOGICAL INTERPRETATION The plant association is very complex and influenced by many biotic and abiotic factors. Some species are restricted in area and adapted to certain ecological conditions while the others have much wider ecological range and easily penetrate from their typical vegetation units into the transitional communities. In addition, fossil evidence from the studied washings is rether limited by a small number of preserved and or determinable plant remains. Therefore, reconstruction of vegetation in the Visonta region may be now given only in general terms. Generally, the plant assemblages obtained from washings of this region represent wetland forest including open water vegetation only with some influence of mesophytic forest, which may be explained by certain drift from outside into the basin. Such inset must be considered as allochthonous component in the studied more or less autochthonous assemblages. The vegetation of wetland forest was rether diverse and differentiated horizontally in the landscape of different physiognomy. That is why almost all found assemblages reflect all 3 main types of the wetland vegetation marginal riparian, swamp and open water vegetation. In the Visonta region, coal-forming swamps are evidenced by Glyptostrobus europaeus which is very common and present in large numbers of twigs, cone-scales and seeds. Swampy plants as Texodium sp., Nyssa disseminata and Helisoma aff. wetteraviensis also occurred, however, they ere rare in our material. Spirematospermum wetzleri belongs together with the latter to the low tree and shrub zone of the swamp forest. Hydrophyte herbs are represented here by Caldesia aff. cylindrica and Oenanthe sp. 61