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AbstractA monolete spore from the upper Permian Raniganj Formation strata of the Madhukunda area in the Damodar Basin is described as Ghoshiasporites manjuaesp. nov. It is laevigate proximally but has a variable densely apiculate ornamentation distally, prompting its classification in the Subinfraturma Varimonoleti and Infraturma Sculptatomonoleti. The diagnostic features of the new species include a characteristic labrum associated with the monolete aperture and the presence of four types of densely placed projections on the distal surface: coni, spines, bacula and clavae. These states clearly distinguish Ghoshiasporites manjuaefrom Ghoshiasporites didecus, the only other varimonolete spore previously recorded from the Permian strata of India.Ashalata D’Rozario [ashalatandc@gmail.com], Centre of Advanced Study, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India; Ahinsuk Barua [dr.ahinsukbarua@gmail.com], South Calcutta Girls’ College, 72, Sarat Bose Road, Kolkata 700 025, India; Subir Bera [berasubir@yahoo.co.in], Centre of Advanced Study, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India.

ABSTRACTPolar transport of the phytohormone auxin is a well-known physiological phenomenon recorded in different extant plant groups including bryophytes and pteridophytes. Earlier, this phenomenon has been recorded in an Upper Devonian (375 million-year) arborescent progymnosperm, Archaeopteris. Since then further record of such occurrence of polar auxin flow is known especially from younger horizons. The present investigation records the evidence of such disrupted polar auxin flow in the form of auxin whirlpool in fossil woods of Tracheidoxyl, Ailanthoxylon indicumand Calophylloxylonsp. from the Middle Oxfordian (Jurassic) to Neogene (Mio-Pliocene) sediments of India.

The infrageneric taxonomy of the genus CephalotaxusSiebold et Zuccarini ex Endlicher (Taxaceae) is controversial as morphological characters have been doubted to change coherently among species. Although the epidermal features are considered as important characters in the taxonomy of conifers, they have not been systematically studied in this genus. Neogene foliage shoots with well-preserved epidermal structure not only can provide systematic links to the extant species, but also have implications for the taxonomical definition of the extant species by their epidermal features. In this paper, the morphologies of leafy shoots combining epidermal structure of a Neogene Cephalotaxus, which was collected from the middle Miocene of Southwest China, and ten extant species (variants) were studied. Morphology as well as epidermal structures was compared among species (variants) in Cephalotaxus. Based on the comparisons, the taxonomical definition of extant species in genus Cephalotaxusare discussed. Our results indicate that leaf morphological characters in combination with the features of epidermal structure can distinguish species in genus Cephalotaxus. The fossil foliage shoots from the middle Miocene of Southwest China were assigned to a new species, C. maguanensisn. sp., which shows close affinities to the extant C. hainanensis. On the basis of leaf and epidermal information, we suggest there are seven extant species in Cephalotaxus. With global cooling and the uplift of the Qinghai-Tibet Plateau since the middle Miocene, the cooling climate induced the differentiation and southward expansions of C. maguanensis, and its extant offspring, C. hainanensis, is distributed to Hainan Island and the Indo-Chinese peninsula.

Die morpho-anatomische Analyse der Stängel, Blätter und Fruktifikationen des zu den Equisetales gehörenden fertilen Triebes von Tulsidabaria indica Banerjee & D’Rozario aus Sedimenten des oberen Unterperm im Saharjuri-Becken, Indisches Unteres Gondwana, ergab bedeutende Merkmale, die sie von den bekannten Pflanzen von Equisetales unterscheiden. Die freien Blätter, die aus den Nodien über dem fertilen Bereich herauswachsen, zeigen einen deutlichen Mittelnerv. Bei der Kutikular-Präparation wurden laterale, streifenartige Verdickungen beobachtet. Tracheiden, die von den Stängeln gewonnen wurden, haben hervortretende, schuppenförmige Verdickungen und gewöhnlich einfache und begrenzte Vertiefungen. Die Fruktifikationen an den Nodien sind tragblattlose Sporangiophoren, welche proximal einfach dichotom verzweigt und im distalen Teil stark verdickt sind. Gruppen von jeweils vier Sporangien befinden sich am Ende der zweifach gegabelten, kurzen Äste; die Sporangien sind in einem semizirkularen Muster an den Sporangiophoren angeordnet. Das Sporangium in der terminalen Position an der letzten Verzweigung wächst aus einem dichten Gewebe heraus, das einer schildförmigen Struktur ähnelt. Die homosporalen Sporangien enthalten Calamospora-artige Sporen. Tulsidabaria hat einige Charakteristika gemeinsam mit den primitiven Equisetales Gattungen Archaeocalamites der Euramerikanischen Flora und Koretrophylhtes, Neokoretrophyllites der Angara-Flora. Tulsidabaria mit ihren unterschiedlichen morpho-anatomischen Merkmalen ist als Vertreter der neuen Familie Tulsidabariaceae innerhalb der Equisetales anzuerkennen. Die morphologische Organisationshöhe der Endverzweigungen der tragblattlosen Fruktifikation von Tulsidabaria kann als intermediäres Stadium in der Evolution der Equisetum-Zapfen gesehen werden.