Carbonised woods resembling extant species of Hydnocarpus (Flacourtiaceae), Anisoptera and Hopea ... more Carbonised woods resembling extant species of Hydnocarpus (Flacourtiaceae), Anisoptera and Hopea (Dipterocarpaceae) and Payena-Pataquium (Sapotaceae) are recorded from the Neogene sediments of Varkala and Payangadi, Kerala coast. They have been named as Hydnocarpoxylon keralaensis sp. nov., Anisopteroxylon varkalaensis sp. nov., Hopenium payangadiensis sp. nov. and Sapotoxylon prepayena sp. nov., respectively. The modern equivalents of these woods are among the important elements of the tropical evergreen forest of Western Ghats, Burma and Malaysia indicating the prevalence of nearly equable warm climate and excessive humid conditions in the area at the time of their deposition during Mio-Pliocene.
The earliest representative of Glossopteridales is known by the leaves discovered from India and ... more The earliest representative of Glossopteridales is known by the leaves discovered from India and Australia (Brongniart 1822–28) under the genus Glossopteris as Glossopteris browniana var. australasica and Glossopteris browniana var. indica. Later discovery proved the presence of similar leaves in all the Gondwana continents, i.e. India, Australia, Antarctica, South America and Africa ranging from late Carboniferous to entire span of Permian to early Triassic. Such distribution pattern provides major evidence for the theory of continental drift. As a unified character, these tongue–shaped leaves show reticulate venation pattern and a midrib. Later, non reticulate and non midrib leaves were also considered as ally due to their close association with the leaves of Glossopteris and together they are assigned to Glossopteridales consisting of different genera, e.g. Gangamopteris, Rubidgea, Euryphyllum, Palaeovittaria, Maheshwariphyllum, Rhabdotaenia, Sagittophyllum, Pteronilssonia, Suran...
Fungal infection (parasitism and saprophytism) in the fossil flora of Deccan Intertrappean sedime... more Fungal infection (parasitism and saprophytism) in the fossil flora of Deccan Intertrappean sediments is well documented from Chhindwara, Dindori, Mandla, Nagpur and Seoni areas of central India. In the present communication, a well preserved dicotyledonous fossil wood showing resemblance with the extant genus Barringtonia Forster & G. Forster of the family Lecythidaceae is recorded for the first time from the Yavatmal District, Maharashtra. The anatomical study of wood reveals that it is endogenously infected with saprophytic fungus Epicoccum Link. ex Schlecht and fungal conidia are profusely distributed in the vessels of the fossil wood. Very fine, ill preserved mycelium is also seen at places. Presence of the genus Barringtonia, as well as fungus Epicoccum is indicative of warm and humid conditions in the area during the time of deposition of intertrappean sediments.
The present paper gives a detailed account of anatomical features of petrified wood showing affin... more The present paper gives a detailed account of anatomical features of petrified wood showing affinities with the modern genus Dryobalanops Gaertn.f. of the family Dipterocarpaceae. The fossil wood was found as a big tree trunk in volcanic sediments near Bogor, West Java (Indonesia). The distribution of extant Dryobalanops is restricted to tropical evergreen rain forests of Malaysia and Indonesia (Sumatra & Borneo). Today it is absent in the natural forests of Java, although the broad climatic setting has not changed much since Pliocene times. Reasons for its absence in the island are discussed.
Plant–insect interaction is dominant in the extant flora and it is estimated that more than one m... more Plant–insect interaction is dominant in the extant flora and it is estimated that more than one million species of insects directly or indirectly survive on plants. In comparison, such association is limited in extinct flora, mainly due to problem in identifying structural features associated with the insect wronged plant fossils. Concerted efforts and comparative structures observed in extant flora have unfolded the mystery of insect herbivory in fossil plants. The study has helped to understand the feeding pattern and evolutionary features of insects during different time intervals and provide significant evidence to comprehend the co–evolution of plant and insect in the geologic past. Herbivorous insect wings discovered from different Gondwana successions of India belong to families and genera of Homoptera, Heteroptera, Mecoptera, Coleoptera and Blattoidea. The remains of Coleoptera and Mecoptera in all probability represent the earliest record in fossil flora. Insect herbivory i...
Carbonised woods resembling extant species of Hydnocarpus (Flacourtiaceae), Anisoptera and Hopea ... more Carbonised woods resembling extant species of Hydnocarpus (Flacourtiaceae), Anisoptera and Hopea (Dipterocarpaceae) and Payena-Pataquium (Sapotaceae) are recorded from the Neogene sediments of Varkala and Payangadi, Kerala coast. They have been named as Hydnocarpoxylon keralaensis sp. nov., Anisopteroxylon varkalaensis sp. nov., Hopenium payangadiensis sp. nov. and Sapotoxylon prepayena sp. nov., respectively. The modern equivalents of these woods are among the important elements of the tropical evergreen forest of Western Ghats, Burma and Malaysia indicating the prevalence of nearly equable warm climate and excessive humid conditions in the area at the time of their deposition during Mio-Pliocene.
The earliest representative of Glossopteridales is known by the leaves discovered from India and ... more The earliest representative of Glossopteridales is known by the leaves discovered from India and Australia (Brongniart 1822–28) under the genus Glossopteris as Glossopteris browniana var. australasica and Glossopteris browniana var. indica. Later discovery proved the presence of similar leaves in all the Gondwana continents, i.e. India, Australia, Antarctica, South America and Africa ranging from late Carboniferous to entire span of Permian to early Triassic. Such distribution pattern provides major evidence for the theory of continental drift. As a unified character, these tongue–shaped leaves show reticulate venation pattern and a midrib. Later, non reticulate and non midrib leaves were also considered as ally due to their close association with the leaves of Glossopteris and together they are assigned to Glossopteridales consisting of different genera, e.g. Gangamopteris, Rubidgea, Euryphyllum, Palaeovittaria, Maheshwariphyllum, Rhabdotaenia, Sagittophyllum, Pteronilssonia, Suran...
Fungal infection (parasitism and saprophytism) in the fossil flora of Deccan Intertrappean sedime... more Fungal infection (parasitism and saprophytism) in the fossil flora of Deccan Intertrappean sediments is well documented from Chhindwara, Dindori, Mandla, Nagpur and Seoni areas of central India. In the present communication, a well preserved dicotyledonous fossil wood showing resemblance with the extant genus Barringtonia Forster & G. Forster of the family Lecythidaceae is recorded for the first time from the Yavatmal District, Maharashtra. The anatomical study of wood reveals that it is endogenously infected with saprophytic fungus Epicoccum Link. ex Schlecht and fungal conidia are profusely distributed in the vessels of the fossil wood. Very fine, ill preserved mycelium is also seen at places. Presence of the genus Barringtonia, as well as fungus Epicoccum is indicative of warm and humid conditions in the area during the time of deposition of intertrappean sediments.
The present paper gives a detailed account of anatomical features of petrified wood showing affin... more The present paper gives a detailed account of anatomical features of petrified wood showing affinities with the modern genus Dryobalanops Gaertn.f. of the family Dipterocarpaceae. The fossil wood was found as a big tree trunk in volcanic sediments near Bogor, West Java (Indonesia). The distribution of extant Dryobalanops is restricted to tropical evergreen rain forests of Malaysia and Indonesia (Sumatra & Borneo). Today it is absent in the natural forests of Java, although the broad climatic setting has not changed much since Pliocene times. Reasons for its absence in the island are discussed.
Plant–insect interaction is dominant in the extant flora and it is estimated that more than one m... more Plant–insect interaction is dominant in the extant flora and it is estimated that more than one million species of insects directly or indirectly survive on plants. In comparison, such association is limited in extinct flora, mainly due to problem in identifying structural features associated with the insect wronged plant fossils. Concerted efforts and comparative structures observed in extant flora have unfolded the mystery of insect herbivory in fossil plants. The study has helped to understand the feeding pattern and evolutionary features of insects during different time intervals and provide significant evidence to comprehend the co–evolution of plant and insect in the geologic past. Herbivorous insect wings discovered from different Gondwana successions of India belong to families and genera of Homoptera, Heteroptera, Mecoptera, Coleoptera and Blattoidea. The remains of Coleoptera and Mecoptera in all probability represent the earliest record in fossil flora. Insect herbivory i...
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Papers by Rashmi Srivastava