Early land plants from the Lower Devonian of central Victoria, Australia, including a new species of Salopella

Abstract

Early land plants with elongate sporangia held in the palaeobotanical archives of Museums Victoria were examined. The fossil plants are from Yea (?upper Silurian) and near Matlock (Lower Devonian) in central Victoria, and are of interest because they contribute to our understanding of the evolution of early land plants in a region in which research has been limited. Both Salopella australis and Salopella caespitosa were originally described over 30 years ago and this reinvestigation has resulted in the emending of the diagnosis of Salopella australis and the erection of a new morphotaxon Salopella laidae sp. nov. based primarily on differing branching architecture and sporangial morphology. Salopella laidae comes from Yea Formation and possesses regular isotomous branching over at least two orders of branching, terminating in elongate sporangia that are wider than their subtending axes, differing from S. australis, which possesses only one dichotomy emanating from at least two erect parallel parent axes with sporangia that are the same width as their subtending axes. A recently collected specimen of Salopella caespitosa was also examined and adds to our understanding of this taxon, which was previously only known from one specimen. Consideration is given to the possible sources of these early land plants based on other early land plants with a similar grade of organisation.

Lower Devonian Zosterophyllum-like plants from central Victoria, Australia, and their significance

“…Following her thesis, she described two rhyniophytoids, Salopella australis and S. caespitosa, and the trimerophyte Dawsonites subarcuatus as occurring in the Wilson Creek Shale at Frenchmans Spur Track, about 10 km west of Matlock (Tims and Chambers, 1984). Recently, Salopella laidae was described from Limestone Road by McSweeney et al 2021c. In the first half of the twentieth century, the lithological sequence that would be later assigned to the Wilson Creek Shale (Edwards et al, 1997;Thomas, 1953;VandenBerg, 1975 was believed to be early Ludlow, upper Silurian, based on Elles's assignation (Lang and Cookson, 1935: 422). Jaeger (1966) reassigned the graptolites to the Lower Devonian based on the occurrence of the monograptids Uncinatograptus thomasi (=Monograptus thomasi thomasi) Jaeger, 1966, throughout the formation, and Neomonograptus notoaequabilis (=M.…”