Five dispersed medullosalean male organs, one species? Late Pennsylvanian Sydney Coalfield, Canada

Abstract

Dispersed medullosalean male organs are found relatively often in the sedimentary record in Pennsylvanian deposits. Specimens are mostly represented by organs which are of the same/very similar shape and size, and preserved are one or more individuals on a single slab, e.g., Laveine (1971) or Schultka (1995). From the Sydney Coalfield, Canada, ten isolated medullosalean male organs of one species are on record all of them collected by first author of this paper from the shale roof of the Lloyd Cove Seam, basal Cantabrian (Fig. 1). Four specimens are described by Zodrow et al. (2017), and one by Zodrow & Mastalerz (2019). Five medullosalean male organs are described in this paper whose exposed compression features differ in size and shape, and who are embedded within a few centimeters of each other. Two interrelated questions arise: (1) What is the reason for the different settling positions in such a limited physical space? As comparison, for example, Barthel & Brauner (2015, fig. 66) and Schultka (1995, pl. 1) confirmed the tendency of the seed-fern organ Whittleseya Newberry to be flatly preserved. (2) More import antly, do these five organs represent one species in five different settling positions, or five different organ species, implying diversity of seed ferns in this Coalfield? Based on their dissimilar appearances, assignment to five different medullosalean male organ species is, perhaps, taxonomically not unreasonable. However, the answer to (2) is revealed by detailed micromorphological study of crucial organ parts. The authors use the generic name Dolerotheca established by Halle (1933). Historically, the specimens of Do le ro theca that consist of four synangial units were se parated and assigned to the new genus Bernaultia by Rothwell & Eggert (1986). However, the complex of inter nal synangial organization of the presented material is unknown in detail; therefore the described material cannot be seriously compared or even placed under the genus Bernaultia sensu Rothwell & Eggert (1986). The authors submit that the present study probably represents one of the more detailed investigation/expe rimentation to date of North American compressions

Polish Palaeobotany: 750 Million Years of Plant History as Revealed in a Century of Studies. Palaeozoic Macrofossils

“…They confirmed the model for the evolution of medullosalean pollen organs proposed by Taylor et al (2009) and placed the new taxa described within it. This paper is an important contribution to knowledge of Carboniferous seed fern pollen organs, cited widely in the international literature (e.g., Serbet et al, 2016;Šimůnek, 2020;Zodrow & Mastalerz, 2019;Zodrow & Pšenička, 2021). Pacyna (2012) critically reviewed studies of Carboniferous and Lower Permian plant reproductive organs from Poland, gave a comprehensive list of taxa published so far, provided a useful dictionary of locality names before and after the border changes of 1945, and clarified the nomenclature and synonymy of taxa described so far from Poland.…”