Rodeites Sahni reinvestigated-I

Abstract

A detailed investigation of Rodeites Sahni from nearly 100 specimens collected from the Deccan Intertrappean beds of India has brought to light some new important facts: (1) The sporocarp wall is thicker and the spores within it are larger than hitherto described. (2) The mode of sorus attachment, observed for the first time, is similar to that of Marsilea rather than Regnellidium. (3) The presence of a distinct cellular gametophyte inside some megaspores is an entirely new finding for the family Marsileaceae. The presence of a male prothallus inside smaller microspores is also newly observed. (4) The occurrence of sporocarps in groups and their attachment are unique. (5) The prismatic layer is distinct in the sporocarp wall of Rodeites The above observations help in reconsidering the position of Rodeites in the Marsileaceae.

Marsileaceae Sporocarps and Spores from the Late Cretaceous of Georgia, U.S.A.

“…Dijkstra (1959) also considered the sporocarp Rodeites to be closely related to Regnellidium. Subsequent work has suggested that although in situ megaspores conform to M. lobata, Rodeites shares several features with Marsilea and is perhaps closer to that genus (Chitaley and Paradkar 1972). Hall (1967) mentioned that he found Crybelosporites microspores associated with Molaspora but did not state with which species and did not illustrate the spores.…”

“…Rodeites dakshini Sahni, emend. Chitaley and Paradkar, from the Deccan Intertrappean Series (latest Maastrichtian?-early Paleocene) of India, is presently the only fossil sporocarp with in situ spores that is attributed to Marsileaceae (Chitaley and Paradkar 1972). Chitaley and Paradkar (1972) argued that this sporocarp most closely resembles Marsilea because of its bilateral symmetry and the attachment of the sori.…”

“…Chitaley and Paradkar, from the Deccan Intertrappean Series (latest Maastrichtian?-early Paleocene) of India, is presently the only fossil sporocarp with in situ spores that is attributed to Marsileaceae (Chitaley and Paradkar 1972). Chitaley and Paradkar (1972) argued that this sporocarp most closely resembles Marsilea because of its bilateral symmetry and the attachment of the sori. Rodeites contains megaspores identical to Molaspora lobata (Dijkstra) Hall, which is distinguished by its baculate perine and acrolamella (Dijkstra 1949;Kovach and Dilcher 1988).…”

Pteridology in the New Millennium

“…Fossil records of Marsileales in India are very poor. After restudy of the specimens, Chitaley and Paradkar (1972) suggested some differences from the modern genus by soral attachment and lack of terminal papilla in the microspores. Courtillot et al (1988) suggested the probable position of the chert bed near the K-T boundary.…”

Cenomanian florule of Nammoura, Lebanon

“…In the lack of well-preserved structural details its taxonomic assignment is admittedly ambiguous. A comparison with aquatic ferns is based on the morphology of both the sterile pinnule and hirsute bodies that resemble, respectively, the floating leaf segments and sporocarpia of extant Marsilea and Regnellidium, as well as those of fossil Rhodeites and Hydropteris (Chitaley & Paradkar, 1972;Rothwell & Stockey, 1994). In these ferns sporocarpia typically attach at the branching nodes of the rhizome.…”