Vine- to lianalike growth habits have to date been documented for a number of late Paleozoic pteridosperm taxa; only a few scrambling and/or climbing taxa, however, have been reconstructed in detail. Pseudomariopteris busquetii (Zeiller) Danzé-Corsin, emend. Krings et Kerp, a (?callistophytalean) taxon that was quite common in the European late Paleozoic, was a medium-sized, vine- to lianalike plant with slender stems to which small bipartite fronds were attached. The growth habit of P. busquetii is reconstructed, based on compression material from the Upper Carboniferous of France and Lower Permian of Germany. P. busquetii utilized two different strategies to both anchor and support the plant body. Most specimens possess specialized climber hooks developed from apical extensions of the pinna axes, indicating that the fronds were used to attach the plant. A few specimens suggest that the stem may also have had some capacity for attachment. In the absence of suitable supports, however, P. busquetii may also have grown in thickets in which the individual plants supported each other. The reconstruction of P. busquetii presented here depicts a growth form which was apparently widely distributed among mariopterid pteridosperms. Several gross-morphological features, which are characteristic of P. busquetii and important for our understanding of its growth form, have also been documented for other mariopterid taxa. Based on local abundance in the fossil record, mariopterid pteridosperms may have played an important role in some of the Upper Carboniferous and Lower Permian coal swamp forest ecosystems. They may have represented part of a rather vigorously growing, sprawling, scrambling and/or climbing type of vegetation that may be structurally comparable to vegetation often found at edges or in disturbed areas (e.g., treefall gaps) of contemporary forest ecosystems.

Key words: climber hooks, growth habit, late Paleozoic, Pseudomariopteris busquetii, Pteridosperms, Reconstruction