Vascular Plant Systematics Dept.

A single, unusual, but highly informative specimen of Trapa LINN• 1753 from Pliocene sediments collected in a gravel-pit within the Zennern Depression, near Fritzlar (Hesse, Germany), has been subjected to detailed investigation. This specimen possesses a unique combination of morphotogical characters when compared to known fossil and extant representatives of the genus Trapa L. and has led to the erection of a new species, Trapa fritzlariensis W£162 et WILDE sp. nov. This species shares se,Jeral characters with the ctosely related genus Hemitrapa MIKI 1941 and appears intermediate to Trapa and Hemitrapa in several ways. In particular, its features fill a gap between the ranges of variability known from the "Trapa" and "Hemitrapa" morphotypes. TrapaJHtzlariensis sp. nov. may prove to be of significance in understanding the evolution of the Trapa-Hemitrapa-eomplex, as it suggests that the two genera are closer than previously recognised and have evolved from a shared cOn]lTl OD ancestor.

A fossil flora is described from the opencast mine Heissler near Hinterschlagen in the Hausruck lignite area (Upper Austria, Late Miocene, Pannonian). The plant remains derive from the top of a clayey seam parting and indicate (shallow) aquatic habitats and species-poor, swampy floodplain forests. Salix hausruckensis Kovar-Eder sp. nov. (leaves) and Trapa ungeri Wójcicki & Kovar-Eder sp. nov. (fruits) are described for the first time.

Fruits of Hemitrapa heissigii Gregor (Trapaceae) have been recognized in the weathered Lom Coal Seam in the northern part of the Most Basin, North Bohemia. This is one of earliest records of this species in Eurasia. The fossil-bearing level is assumed to be of late Early Miocene age (approximately late Eggenburgian to Karpatian of the Paratethys regional stratigraphy). All the other megafossils from the Most Basin, which have been determined as belonging to Trapa, are either poorly preserved, not determinable to the generic level, or not belonging to the Trapaceae.

Fossil fruits of Trapa from the Late Miocene sediments of Soś nica (SW Poland), described by Goeppert as Trapa silesiaca and T. bifrons, are revised and re-illustrated. The discovery of additional morphological features has enabled a precise characterization of T. silesiaca to be realized with resultant emendation of its diagnosis. The lectotype of T. silesiaca is formally designated and an epitype selected for the purpose of providing a precise application of the name T. silesiaca. Studies of specimens from the original collection determined by Goeppert as T. bifrons confirmed earlier suggestions that this species is conspecific with T. silesiaca. The correct citation of Trapa assmanniana (Goeppert) Gothan in Potonié described and illustrated by Goeppert from Sośnica as Populus assmanniana is provided. The taphocoenosis of fossil plants from Sośnica is also briefly characterized.

The plant remains from a hydrophyte-bearing pelite of the sedimentary sequence at Pellendorf, Lower Austria (Miocene, Pannonian "zone" C) are investigated taxonomically. Mikia pellendorfensis Kovar-Eder & Wójcicki gen. et sp. nov. most probably represents floating leaves of a rooted aquatic plant. These leaves possibly belong to the plant that produced Hemitrapa trapelloidea Miki fruits. Trapa pellendorfensis Wójcicki & Kovar-Eder sp. nov. (fruits) co-occurs with H. trapelloidea even on the same bedding planes. The lower, approximately 2.7 m thick part of the investigated pelite is characterized by a mass-occurrence (monodominant) of Decodon leaves. In the upper approximately 1.1 m species are more diverse in aquatic plants: Nitellopsis majoriformis (Papp) Schwarz comb. nov., Stephanochara aff. rochettiana (Heer) Feist-Castel, Ceratophyllum schrotzburgense Hantke, Ceratophyllum sp. (fruits), Nymphaeaceae (rhizome fragments), Hemitrapa trapelloidea, Trapa pellendorfensis, Mikia pellendorfensis, and Potamogeton sp. (fruits) are documented there. The presented results here are fundamental for the palaeoecological interpretation of the whole sedimentary sequence at Pellendorf.

Fossil fruits of Trapa L. and Hemitrapa Miki (Trapaceae) known from eight late Miocene Austrian localities are characterized. Fruits morphologically intermediate between Trapa ungeri Wójcicki & Kovar-Eder and T. srodoniana Wójcicki from Hinterschlagen (Upper Austria, Pannonian) are described as a new species T. spectabilis Wójcicki & Kovar-Eder sp. nov. Additional morphological characteristics of T. srodoniana are provided and the species description is emended. The description of T. silesiaca Göpp. emend. Wójcicki & Zastawniak is supplemented and numerous specimens from Austria are fi gured. Fossil fruits and pollen of defi nite Trapaceae (Trapa L., Hemitrapa Miki) and leaves of probable Trapaceae affi nity (Mikia Kovar-Eder & Wójcicki)