Ecology And Growth Habit Of Laveineopteris: A Gymnosperm from the Late Carboniferous Tropical Rain Forests

Abstract

ABSTRACT. Cyclopterid leaves were borne on the same Late Carboniferous medullosalean plants that bore the pinnate fronds currently known as Laveineopteris. They were morphologically and anatomically different from the pinnate foliage, and presumably were also physiologically different. The cyclopterids are here interpreted as having been shade leaves and the pinnate foliage sun leaves. The juvenile Laveineopteris plant probably consisted of a monopole sapling bearing only cyclopterid leaves, which optimized growth in canopy shade conditions. On reaching the canopy level, the plant produced a crown of pinnate sun leaves. Cyclopterids were also borne epiphyllously in the proximal parts of the pinnate fronds; this may have represented a transitional light-level between canopy and subcanopy conditions. Thus, in this reconstruction, the cyclopterid leaves were complementary to the pinnate foliage of the adult Laveineopteris plant, and played a key role in its growth habit and ecology.

T0 peat-forming plant assemblage preserved in growth position by volcanic ash-fall: A case study from the Middle Pennsylvanian of the Czech Republic

“…It is assumed that this species was relatively a small tree, and that a main stem 80 mm wide may well have been that of a fully mature plant. Paralel explanation that it was a small, prereproductive, juvenile plant does not seem correct since Shute & Cleal (2002) suggested that juvenile Laveineopteris had cyclopterid rather than pinnate foliage. However, no cyclopterids have been found.…”

Palaeoecology of Macroneuropteris scheuchzeri, and its implications for resolving the paradox of ‘xeromorphic’ plants in Pennsylvanian wetlands

“…However, not all pteridosperms were xeromorphic. Some, such as Laveineopteris rarinervis, lack xeromorphic characteristics and may have been understory/ subcanopy plants (Shute and Cleal, 2002), which would have buffered their physiologies to some degree from the potential CO 2 -O 2 interaction.…”

Systematics of the Late Carboniferous Medullosalean Pteridosperm Laveineopteris and Its Associated Cyclopteris Leaves

“…We have prepared cuticles from a number of cyclopterids and their associated laveineopterid fronds, some of which were described by Shute and Cleal (2002). The others were not included in our earlier paper as they did not signi®cantly improve our understanding of the functional signi®cance of cyclopterids.…”

“…Nowadays, however, it tends to be used only for leaves attached to a group of Late Carboniferous medullosalean trees that also had fronds referred to as Laveineopteris, Callipteridium and Margaritopteris. In a recent paper, we described some exceptionally well-preserved cyclopterid cuticles that helped to explain the functional signi®cance of these enigmatic foliar organs (Shute and Cleal 2002). We argued that the cyclopterids were shade leaves on juvenile trees growing through the dense undergrowth, or were attached to those parts of the adult trees that were not fully exposed above the canopy.…”

“…We therefore document these cuticles here and use them as an opportunity to revise the systematics of both Cyclopteris and Laveineopteris. Cuticles were prepared using the same method as in Cleal and Zodrow (1989), Cleal and Shute (1992), and Shute and Cleal (2002). The phytoleim was released from the rock matrix using hydro¯uoric acid, and then macerated using Schulze's Solution.…”