Pertica, a New Genus of Devonian Plants From Northern Maine

Abstract

A new genus of Devonian age fossil plants is described from the Trout Valley Formation of northern Maine. Abundant compression material permits a rather complete understanding of its morphology. Pertica quadrifaria Kasper and Andrews, gen. et sp. nov., was an erect plant, perhaps a meter tall, with a pseudomonopodial main axis and dichotomous side branches. The side branches were arranged in a clockwise spiral (from base to apex) and were tetrastichous. They dichotomized numerous times, with the intervals between dichotomies decreasing distally. The ultimate branchlets bore numerous sporangia in dense clusters. Other side branches were completely sterile. Pertica quadrifaria is classified in the Subdivision Trimerophytina of Banks. Its evolutionary significance rests in the fact that it is a link in the chain of increasingly complex early vascular land plants.

The oldest flora of the South China Block, and the stratigraphic bearings of the plant remains from the Ngoc Vung Series, northern Vietnam

“…The oldest plant displaying axis around 1.5 cm thick is Pertica Kasper and Andrews, 1972. Pertica is a basal euphyllophyte from the Trout Valley Formation, Maine, USA, which is LateEmsian-Early Eifelian in age (Kasper and Andrews, 1972).…”

Tenuisa frasnianagen. et sp. nov., a Plant of Euphyllophyte Affinity from the Late Devonian of China

“…Pertica is composed of three species, P. quadrifaria (Kasper and Andrews 1972), P. varia (Granoff et al 1976), and P. dalhousii (Doran et al 1978). Although P. varia has fertile lateral units with pseudomonopodial branching and subopposite arrangement, Pertica as a whole differs from the Chinese plant in the distinct main axis, helical laterals, and erect sporangia that are sessile and of larger size (2-5 mm long and 1-1.5 mm wide vs. 0.9-[1.3]-1.6 mm long and ca.…”

Plant Paleoecology in Deep Time1

“…Such reconstructions have been effected directly and most often from compression fossils, some of which also have anatomical details preserved via permineralization. A few examples include the enigmatic fungus Prototaxites Dawson (Hueber, 2001;Boyce et al, 2007), the lycopsid Sawdonia ornata (Dawson) F. M. Hueber (Hueber, 1971), the trimerophyte Pertica quadrifaria Kasper & Andrews (Kasper & Andrews, 1972;Gensel & Andrews, 1984), and numerous plants from the classic Rhynie Chert in Scotland, which usually have been reconstructed by finding parts attached in series rather than as single whole plants (Paleobotanical Research Group, University of Mü nster, 2007). One of the most puzzling nearly whole plants is Cooksonia W. H. Lang, often touted as the earliest vascular land plant but known only from aerial parts (Edwards et al, 1992).…”