Shaila Chandra

The genus Glossopteris from the Late Permian beds of Handapa, Orissa, India

Forty two species of the form genus Glossopteris have been reported from Hinjrida Ghati section, near Handapa village in Dhenkanal District of Orissa. This is the first report of such a large number of species of this genus from a single locality and formation from India and perhaps from the Southern Hemisphere. The huge collection of Glossopteris specimens, with a great diversification of species, clearly indicates that the genus Glossopteris grew as luxuriantly in the Kamthi Formation as in the equivalent Raniganj Formation, both of Late Permian age. Abundant leaves of Glossopteris in the fine sediments indicate seasonal falling and favourable conditions for plant growth. A vegetational reconstruction of the Handapa area representing Late Permian time is attempted. It is assumed that the thick forest must have been dominated by a variety of Glossopteris trees and shrubs with small patches of open area for the development of pteridophytic plants as undergrowths as shown by the composite fossil flora of the beds.

Reinvestigation of the coniferophyte morphospecies Buriadia heterophylla Seward and Sahni, with reinterpretation of vegetative diversity and putative seed attachments

Abstract The Gondwana coniferophyte Buriadia heterophylla Seward and Sahni is reinvestigated from newly discovered material in eastern India, from previously described specimens of Buriadia florinii Maithy, and from specimens of B. heterophylla and Birsinghia florinii Pant, Nautiyal and Chaturvedi that previously were described as having attached seeds. Vegetative morphology and cuticular features for all of these Permian specimens from India conform to unimodal ranges of variation, and are reinterpreted as a single species. Horned seeds are commonly associated with the vegetative remains at most localities, but re-examination of specimens previously described as having attached seeds reveals that no seeds are preserved in organic connection to shoots. All of the specimens of vegetative remains are recognized as belonging to a single morphospecies, B. heterophylla Seward and Sahni that consists of compressed leafy shoots displaying distinct cuticular features as well as larger stems with some wood anatomy. The reproductive structures of B. heterophylla are unknown.

The Late Permian sporangiate fructification Nesowalesia edwardsii Pant, 1977, from Katoomba, New South Wales, Australia

Abstract Additional information is presented concerning Nesowalesia edwardsii Pant, 1977, a peltate discoid structure of unknown affinity bearing numerous Arberiella sporangia based on specimens from the Late Permian Illawarra Coal Measures of the western Sydney Basin, New South Wales. Sporangia contain the taeniate bisaccate pollen Striatopodocarpites solitus (Bharadwaj and Salujha) Foster, 1979. The fructification may have been part of a plant that bore leaves of Glossopteris .

Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya

Cleal, C.J., Bhat, G.M., Singh, K.J., Dar, A.M., Saxena, A. & Chandra, S., February 2016. Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya. Alcheringa 40, xxx–xxx. ISSN 0311-5518. The Sepukhovian fossil floras of the northern margins of Gondwana, on the shores of the Palaeotethys, are dominated by remains of an eligulate, mainly monopodial lycopsid with persistent leaves. The stems show considerable morphological and preservational variation that has historically resulted in the fossils having been assigned to many fossil-species and -genera. However, there is now clear evidence that this simply reflects variation within a single fossil-species, reflecting biological variation and the effects of variable taphonomy, for which the correct taxonomic name is Spondylodendron pranabii (Pal) comb. nov. Part of this morphological variation might have been due to variations in growth rate during the life of the individual plants, which in turn might reflect stressed growing conditions in a wetland habitat. The systematic position of Spondylodendron remains uncertain, owing to the lack of unequivocal evidence of reproductive structures, but it might have affinities with the Sublepidodendraceae. Christopher J. Cleal [chris.cleal@museumwales.ac.uk], Department of Natural Sciences, National Museum Wales, Cathays Park, Cardiff CF10 3NP, UK; G.M. Bhat [bhatgm@jugaa.com] and A.M. Dar, Department of Geology, University of Jammu, Jammu, India; Kamal Jeet Singh, [kamaljeet31@hotmail.com] and Anju Saxena [anju_saxena2002@yahoo.co.in], Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, (U.P.) India; Shaila Chandra, Flat Number 105, Beverly Park Apartment 422, New Hyderabad, Lucknow-226007, (U.P.) India.

Carboniferous floras in siliciclastic rocks of Kashmir Himalaya, India and the evolutionary history of the Tethyan Basin

The Fenestella Shale Formation of Jammu and Kashmir Himalaya comprises latest Visean or Serpukhovian siliciclastic deposits formed along the southern margins of the Palaeotethys Ocean. A sequence of shallowing upward and deepening upward units indicates changes from shoreface to offshore and deeper shelf conditions, probably controlled by eustatic changes in an otherwise passive depositional system. Some of the finer-grained, shallow marine deposits have yielded fossil floras dominated by sub-arborescent lycopsids ( Sublepidodendron , Lepidodendropsis ) sphenophytes ( Archaeocalamites ) and pteridophylls ( Nothorhacopteris , Triphyllopteris ). The assemblage compares with other Gondwanan floras of this age that have been assigned to the Paraca floral realm, and are taken to indicate relatively warm climatic conditions that existed just prior to the onset of the Carboniferous–Permian ice-age.

Spore tetrads, possible indicators of intense climatic regimes: case study from an early Permian stratum of Singrauli Coalfield, Son-Mahanadi Basin, India

A large number of naked, fossil spore tetrads assignable to the dispersed microspore genera Indotriradites, Microbaculispora and Microfoveolatispora are reported for the first time from an early Permian stratum (Lower Barakar Formation) of Singrauli Coalfield, Son-Mahanadi Basin, Central India. This is also the first record of tetrads from any Artinskian strata in the world. There is no evidence of any kind of sporangia or related plant parts in the present investigation that could ascertain the affinity of these tetrads; however, the presence of a trilete mark in the spores of the tetrads demonstrates their alliance at least with the pteridophyte group. The present study suggests possible factors affecting the sporogenesis process in the past, considering other available global records pertaining to fossil spore tetrads. The results of significant physiological and biochemical analyses performed on the anthers of modern plants related to reproductive biology, in order to understand the conditions and changes responsible for the formation of tetrads, are also considered. We analysed the globally occurring fossil tetrads and the palaeoclimates prevailing during their deposition. A correlation between extreme climatic conditions, specific pH values inside microsporangium and the formation of tetrad is envisaged. It is deduced that extreme climatic conditions (extreme cold/extreme hot) might have triggered some sort of malfunctioning in the sporogenesis process that altered the specific pH values inside the microsporangium. Any restraint of the activity of the callase enzyme, responsible for dissolution of callose walls laid between the individual spores, may therefore have apprehended the dissociation of tetrads into individual spores.