Browsing by Author "Sharma, K. Milankumar"

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Chondrichthyan and osteichthyan fauna from the middle Miocene deposits of Palasava, Kutch, India: implication for paleoenvironment and paleobiogeography; [Faune de chondrichtyens et d�ost�ichtyens provenant des d�p�ts du Mioc�ne moyen de Palasava, Kutch, Inde: implication pour le pal�oenvironnement et la pal�obiog�ographie]
(Academie des sciences, 2022-12-13T00:00:00) Singh, Nongmaithem Amardas; Choudhary, Deepak; Singh, Y. Priyananda; Singh, Ningthoujam Premjit; Patnaik, Rajeev; Tiwari, R.P.; Sharma, K. Milankumar
The Neogene of Kutch, India is well known for its rich marine and terrestrial vertebrate assemblages. However, the data of piscean fauna from the middle Miocene of India is very scarce. We report here additional chondrichthyan and osteichthyan remains from the middle Miocene deposit of Chhasra Formation, Palasava site, Kutch, Gujarat, India. The elasmobranchs include Carcharhinus Blainville, 1816 (C. brevipinna (M�ller & Henle, 1839), C. falciformis (M�ller & Henle, 1839), C. cf. leucas, C. aff. perezi, Carcharhinus sp.), Negaprion Whitley, 1940 (Negaprion sp.), Aetobatus Blainville, 1816 (Aetobatus sp.), Myliobatis Cuvier, 1816 (Myliobatis sp.), Dasyatis Rafinesque, 1810 (D. probsti Cappetta, 1970, D. rugosa Probst, 1877), Himantura M�ller & Henle, 1837 (H. menoni Sahni & Mehrotra, 1981), Pastinachus R�ppell, 1829 (Pastinachus sp.), and Taeniurops Garman, 1913 (Taeniurops sp.). The teleosts of Palasava are represented by four families including Bagridae Bleeker, 1858, Channidae Fowler, 1934, Characidae Latreille, 1925 and Cyprinidae Cuvier, 1817. S�rensen-Dice coefficient data of Palasava elasmobranchs show a good similarity index with their counterparts in the Mediterranean Sea suggesting the existence of short-lived reopening of the marine pathway. However, a much higher faunal affinity with those of Eastern Pacific indicates a gradual shift in migration path through the Pacific Ocean to Indo-Pacific region after the permanent landbridge was formed. The vertebrate fauna from the Palasava suggests a coastal, marginal marine, near-shore littoral to neritic environment of deposition with the influence of freshwater riverine system. The integration of the floras and faunas from Palasava locality indicates the presence of warm, humid/ wet, tropical to sub-tropical environmental conditions during the middle Miocene. � 2022 Elsevier Masson SAS. All rights reserved.
First report on late Miocene (Tortonian: ~ 11�10�Ma) charophyte gyrogonites from Tapar, Kachchh District, Gujarat State, western India
(Springer Nature, 2022-09-05T00:00:00) Singh, Nongmaithem Amardas; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Patnaik, Rajeev; Tiwari, R.P.; Sehgal, Ramesh Kumar; Kumar, Vinay; Wazir, Wasim Abass; Singh, Y. Priyananda; Choudhary, Deepak
This paper describes the first record of charophyte gyrogonites from the late Miocene (Tortonian; ~ 11�10�Ma) Tapar locality of Kachchh, Gujarat State, western India. The recovered charophyte assemblage is constituted by Chara globularis var. aspera, C. globularis var. globularis, Lychnothamnus cf. sahnii, Lychnothamnus sp. and Nitellopsis sp. In addition, the present article discusses the palaeoenvironment based on the recorded charophyte gyrogonites (this study) and previously known faunal data (mainly vertebrates) from the Tapar locality, Kutch Basin, western India. Further, considering the significant extension of the biostratigraphic range [especially the First Appearance Datum (FAD)] of fauna from the Kutch Basin (in particular from the Tapar locality), we herein make an attempt to compare biostratigraphically the faunal assemblages from Kutch with those from the Siwalik Group, north India. � 2022, Indian National Science Academy.
Lepidosauromorphs and associated vertebrate fauna from the Late Triassic Tiki Formation, South Rewa, Gondwana basin, India: implication for paleoenvironment and paleobiogeography
(Springer Nature, 2023-03-27T00:00:00) Singh, Y. Priyananda; Sharma, K. Milankumar; Tiwari, Raghavendra Prasad; Patnaik, Rajeev; Singh, Nongmaithem Amardas; Singh, Ningthoujam Premjit
Tiki Formation is well known for the presence of rich vertebrate fossil assemblages including archosaurians, cynodonts, xenacanthids, hybodonts and actinopterygians in the Gondwana succession of India. Here, we report indeterminate Sphenodontia and indeterminate Lepidosauromorpha from the Late Triassic Tiki Formation. The presently reported early diverging lepidosauromorphs might have fed on small invertebrates and small vertebrates/insects. The presence of early diverging lepidosauromorphs from the Tiki Formation extends their geographic range from Europe, N. America and S. America to the Indian sub-continent during the Late Triassic Period. Further, the reports of archosauromorph assemblages and the aquatic vertebrates from the Tiki Formation have strengthened the idea of affinities of vertebrate assemblages between Laurasia and Gondwana sub-continents of the Pangea. � 2023, Indian National Science Academy.
Listriodon dukkar sp. nov. (Suidae, Artiodactyla, Mammalia) from the late Miocene of Pasuda (Gujarat, India): the decline and extinction of the Listriodontinae
(Springer Science and Business Media Deutschland GmbH, 2022-03-17T00:00:00) van der Made, Jan; Choudhary, Deepak; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Singh, Nongmaithem Amardas; Patnaik, Rajeev
The Listriodontinae were a common and widespread group of Suidae (pigs) that lived in an area extending from Portugal to China and to southern Africa. Here, we describe the new species Listriodon dukkar from Pasuda (Gujarat, India). It shares features with Li. pentapotamiae, evolved from it, and is the last representative of this lineage. The Listriodontinae flourished for about 10 million years, reached their maximum diversity and geographic extension during the Mid-Miocene Climatic Optimum (about 17�13.6�Ma), and their last records are close in age and date to�~ 9.8�Ma in the Indian Subcontinent, 9.78�Ma in Europe, and ~ 10�Ma in Africa. We review the environments in which the last listriodont lineages lived and went extinct. Their extinctions occurred against a background of increasing seasonality, vegetation change, a rise in bovid diversity and abundance, and local events, such as the European Vallesian Crisis and a dramatic drop in tragulid abundance in the Siwaliks. However, changes in the atmospheric pCO2 may have contributed to their decline and extinction in all their geographic distribution. Decreasing pCO2 is expected to have decreased sugar content and increased protein content of leaves and fruit. Hindgut fermenting Suoidea have higher protein requirements, while foregut fermenting Suoidea are more efficient in digesting sugars. Listriodontinae were probably foregut fermenters and were less well adapted in a low pCO2 world. � 2022, The Author(s).
Lithostratigraphy, trace fossils and palaeoenvironment of Paleogene sequences in Parwanoo-Subathu sector of Himachal Himalaya, India
(Geological Society of India, 2018) Singh, Ram Jivan; Sharma, K. Milankumar; Kumar, Pankaj; Ghosh, T.
The Paleogene belt of the Outer Himalaya in the Shimla Hills is represented by the Paleocene to Lower Miocene ma-rine to ?uvial rocks of the Sirmur Group which is divisible into the Subathu, Dagshai and Kasauli formations in younging order in Parwanoo-Subathu area of the Himachal Pradesh, India. The shallow marine fossil bearing Subathu Formation overlies the various Proterozoic lithostratigraphic units like the Simla Group, Krol Group, Baliana Group, Shali Group/Deoban Group and others with an unconformable contact marked by a thin layer of oxidized and ferruginised laterite, indicating prevalence of warm tropical climate before deposition of these shallow transgressive marine rocks. The Subathu Formation grades upward into ?uvial deposits,compris-ing an alternate sequence of reddish-purple mudstone and ?ne to medium grained, reddish-brown sandstone of the Dagshai Formation along with multiple palaeosol horizons. The rocks of the Dagshai Formation are further gradationally overlain by the plant fossil bear-ing ?uvial sequence of medium to coarse grained, massive, multistory, greenish-grey micaceous sandstone and minor grey-orange mudstone of the Kasauli Formation. In response to southward leading deformation front of the Himalayan orogeny, due to collision tectonics of the Indian and Eurasian plates, the para-autochthonous Paleogene fold-thrust belt exposed between the northerly dipping Main Boundary Thrust (MBT)/Krol Thrust in north and the Main Boundary Fault (MBF) in the south shows repetition of some forma-tions of the Sirmur Group along Parwanoo-Darampur-Barog-Subathu section of the Himachal Himalaya. The abundance of vertical and cylindrical burrows of Skolithos linearis, S. annulatus, S. ingen, S. bulbus, Ophiomorpha esp., Thallasinoides paradoxides, etc. within the upper part of the Subathu Formation suggest lower intertidal to subtidal environment. This ichnofossil assemblage along with Skolithos-Thallasinoids-Ophiomorpha represent littoral zone, intertidal to subtidal environment of deposition
Microfossil Assemblage from Dhok Pathan Formation (Middle Siwaliks) exposed near Polian Prohita, Una District, Himachal Pradesh, India
(The Society of Earth Scientists, 2015) Sharma, K. Milankumar; Singh, Shyam Sundar; P.V., Vipina
The Fluvial molassic sediments of Middle Siwalik which is considered to be deposited within the time range from 10.1-5.1 Ma holds a long record of the provenance and palaeoenvironmental history of Siwalik foreland basin. A mudstone bed of Dhok Pathan Formation exposed near Polian Prohita, Una district, Himachal Pradesh has yielded a diverse fossil assemblage. The present assemblage include mollusks Parreysia sp., Lamillidens sp., Melanoides sp. and Gyraulus sp. The charophytes include Chara globularis globularis, Chara globularis aspera, Chara sp. indet, Lychnothamus breviovatus and Lamprothamnium papulosum. Ostracodes Stenocypris sp. and Candona sp. have also been reported here. Fish teeth of certain morphotypes belonging to the Channidae and Cyprinidae families were also recorded. The majority of the fossil assemblage suggested that a warm tropical to subtropical humid climatic condition was prevailing during the deposition of these sediments. As this fossil assemblage is found restricted to a particular mudstone bed it can be inferred that there existed a localized swampy to overbank pond environment in within the braided river system deposits of Dhok Pathan Formation.
The Miocene fossil lizards from Kutch (Gujarat), India: A rare window to the past diversity of this subcontinent
(Cambridge University Press, 2021-09-06T00:00:00) ?er?ansk�, Andrej; Singh, Ningthoujam Premjit; Patnaik, Rajeev; Sharma, K. Milankumar; Tiwari, Raghavendra Prasad; Sehgal, Ramesh Kumar; Singh, Nongmaithem Amardas; Choudhary, Deepak
The Miocene beds of Kutch in India are well known for their mammalian assemblages, including the extinct ape Sivapithecus, but far less is known about the fossil squamates from this area. Although India with its over 800 reptile species is recognized as one of the global biodiversity hotspots, knowledge of past diversity and paleobiogeography of squamates on this subcontinent is very limited. We here report on new lizard finds, which have been recovered from two stratigraphic levels: the older Palasava locality (dated to the middle Miocene, ca. 14 Ma) and the younger Tapar site (late Miocene, ca. 11-10 Ma). Although fragmentarily preserved, the material described here sheds important light on the composition and paleobiogeography of squamates during the Miocene in South Asia. The older Palasava locality contains cf. Uromastyx s.l. and Varanus sp., the latter representing the oldest record of this taxon in the region of India south of the Himalayas and its occurrence here suggests a mean annual temperature not less than 15�C. The material from the younger Tapar locality consists of an unidentified acrodontan lizard, here questionably placed in agamids, and a skink. The latter shows a resemblance to mabuyines, however, the fragmentary nature of the material does not allow a precise allocation without doubts. The cosmopolitan mabuyines have been suggested to have their origin in Asia, so the potential presence of mabuyines in the Tapar locality might represent the first, but putative, Asian evidence of the occurrence of this group in the Miocene. Copyright � The Author(s), 2021. Published by Cambridge University Press on behalf of The Paleontological Society.
New rodents shed light on the age and ecology of late Miocene ape locality of Tapar (Gujarat, India)
(Taylor and Francis Ltd., 2022-08-05T00:00:00) Patnaik, Rajeev; Singh, Ningthoujam Premjit; Sharma, K. Milankumar; Singh, Nongmaithem Amardas; Choudhary, Deepak; Singh, Y. Priyananda; Kumar, Rohit; Wazir, Wasim Abass; Sahni, Ashok
The Miocene ape (Sivapithecus) locality of Tapar in Kutch (Gujarat, India) has yielded a diverse rodent assemblage that includes: a new murine Progonomys prasadi sp. nov., a new gerbilline Myocricetodon gujaratensis sp. nov., a new rhizomyne Kanisamys kutchensis sp. nov. and a new sciurine Tamias gilaharee sp. nov., beside additional remains of Progonomys morganae, Dakkamys asiaticus, Prokanisamys sp., Sayimys sivalensis and Democricetodon fejfari. Morphometric and PAUP based phylogenetic analyses place Progonomys prasadi sp. nov. within the Progonomys lineage. The cladogram obtained for the Siwalik murines suggest that Progonomys was ancestral to all the modern and one extinct murine genera recovered from the Siwaliks. The advanced features of Myocricetodon gujaratensis sp. nov. indicate that it was an immigrant to the subcontinent in the late Miocene. The cladistic analysis performed on Kanisamys kutchensis sp. nov. shows that it shared several advanced characters with contemporaneous Kanisamys nagrii and Kanisamys sivalensis. Based on the biostratigraphical ranges of Siwalik rodents and the co-occurrence of advanced forms of new and already reported murines, a new gerbilline and a new sciurine, we propose an age of ?10 Ma to the primate-bearing Tapar locality. Already reported stable isotope data on murines, and ecological preferences of modern counterparts of the fossil rodents and associated sharks and rays from Tapar locality, indicate that the Miocene ape Sivapithecus may have lived in a subtropical monsoonal forest close to the coast, very different from the present day arid conditions. http://zoobank.org/urn:lsid:zoobank.org:pub:12CE1B44-22A0-450F-9588-6C7F25242771. � The Trustees of the Natural History Museum, London 2022. All rights reserved.
Phytosaurian Osteoderms From The Late Triassic Tiki Formation (Shahdol District, Madhya Pradesh), India
(The Palaeontological Society of India, 2015) Sharma, K. Milankumar; Kumar, Jitendra
The Late Triassic fossiliferous deposits of the Tiki Fomation of the South Rewa Gondwana Basin of India, is well known for its vertebrate fossil assemblages including temnospondyl tetrapods, archosauroform rhynchosaur, and several crurotarsans such as phytosaurs and rauisuchids. The present paper describes some phytosaurid osteoderm remains for the ?rst time from the Tiki Formation. These osteoderms are found together with phytosaurian teeth, jaw and vertebrae. On the basis of their texture, shape, size, morphology and association with phytosaurian remains, the present specimens have been assigned to phytosaurids
Study Of Microfossils (Foraminifers) From The Khari Nadi Formation Of Jangadia Section Kutch: Palaeoenvironmental Implication
(Central University of Punjab, 2018) Haobijam, Johnson; Sharma, K. Milankumar
The study area lies in the Kutch of Gujarat which is western most part of the Indian subcontinent. This dissertation attempts to study the systematic palaentology of the foraminifera and palaeoenvironment of the Khari Nadi formation of Jangadia section of lower Miocene time. After the thorough study and taking photograph by using trinocular sterozoom microscope nearly 160 specimen are found and most of them are benthic foraminifera and only few of them are planktonic. The benthic foraminifera is best to study the palaeoenvironment of the particular area. The specimen Elphidium are found at the lagoonal environment. Quinqueloculina and triloculina are found in the nearshore environment. Nonion and Nonionella are found in the outerself environment. So, the Khari Nadi formation of Jhangadia section was lagoonal to upperslope environment during the time of lower Miocene which the was slowly transgressive over a stable shelf