Acta Biologica Tomus XXIII. Fasciculi 1-4. [antikvár]

Acta Biologica Szeged. 23 (1—4), pp. 3—17 (1977) GLEICHENIACEAE SPORES FROM LOWER CRCTACEOUS DEPOSITS OF HUNGARY M. Juhász Department of Botany, Attila József University, Szeged (Received September 30, 1976) Abstract The present palynological study discusses Gleicheniaceae-type spores isolated from the Lower Cretaceous sediments of Hungary. Twenty species were identified and placed into the following organgenera as follows: Gleicheniidites (11 species), Clavifera (4 species), Plicifera (2 species), and Ornamentifera (3 species). Stratigraphically the Gleicheniaceae spores play an important part in the spore-pollen complexes of the Upper Barremian to Lower Aptian deposits of the Mts Bakony, and Albian sediments of the Mts Villány, where mainly species of the Gleicheniidites and Plicifera organgenera predominate. Both the actual number of spores and the number of species decreases for the Gleicheniaceae spores in the Albian assemblages of the Transdanubian Central Mts, but here appear the typical forms of the Ornamentifera and Clavifera species. Introduction The Gleicheniaceae is one of the FiUcales order widest known ancient fern famihes. The recent Gleicheniaceae species number about 160. Their zone of distribution ranges from the Korean pensinula and Florida to New Zealand (Seward, 1912). The shoots of recent species usually crawl on the ground or are slightly raised; in the latter instances they climb on shrubs or trees. Their sori are arranged in row, lack indusia, and have few (2—8) sporangia. The spores are trilete or monolete homoiospores. The Gleicheniaceae ancestral representatives have been traced from the Carboniferous age, but significantly they became widespread only in the Mesozoic. The number of fossil leaf records traced from Jurassic and Cretaceous is large. We can find the tabulated summary of these megafossils in the excellent work of Bolchovitina (1968). The associated and dispersed „gleicheniid" spores of Lower Cretaceous rocks are very similar to modern Gleicheniaceae spores. Shared characteristics of the modern and fossil „gleicheniid" spores are the following: triangular equatorial outline; interradial crassitudes at the equator; presence of arcuate folds on the distal surface; usually smooth, rarely ornamented exosporium.