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42 results on '"Paudayal, Khum N."'

14. Menatanthus mosbruggeri gen. nov. et sp. nov. – A flower with in situ pollen tetrads from the Paleocene maar lake of Menat (Puy-de-Dôme, France)

Author

Uhl, Dieter, Paudayal, Khum N., Hervet, Sophie, El Atfy, Haytham, Senckenberg Forschungsinstitut und Naturmuseum Frankfurt, Frankfurt am Main, Germany, Central Department of Geology, Tribhuvan University, Kirtipur, Nepal, Association Paléovergne, Musée de Menat, Menat, France, and Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt

Subjects
0106 biological sciences, 010506 paleontology, ddc:561, Stamen, medicine.disease_cause, Tribe (biology), Bejaria, 010603 evolutionary biology, 01 natural sciences, Fossil-Lagerstätte, Genus, Pollen, Heptamerous flower, Botany, medicine, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Global and Planetary Change, Ecology, biology, Kalmia, Paleontology, Ericipites ericius, Geology, biology.organism_classification, Kalmia-type pollen, Maar, Taxon, Ericaceae
Abstract

The Paleocene Fossil-Lagerstätte Menat in France is well known for its wealth of outstandingly well preserved fossil insects and plants. Despite being known for more than a century, the palaeoflora, which is regarded as typical for the late Thanetian by some authors, has largely been neglected since the 1940s. New excavations and surveys yielded exceptionally well-preserved plant material, including a minute, heptamerous flower bearing in situ pollen tetrads, comparable to tetrads of the modern ericacean genus Kalmia L, in its anthers. The only known modern ericacean genus which is characterised by heptamerous flowers is Bejaria Mutis ex L., a basal relative of the tribe Phyllodoceae within Ericaceae, which also includes the genus Kalmia in a relatively basal position. However, heptamerous flowers also occur very rarely (mostly interpreted as teratologies) in a number of other modern Ericaceae, but also in various other modern angiosperm families. Due to the unique combination of a heptamerous flower with Kalmia-type pollen tetrads within the anthers, the new taxon Menatanthus mosbruggeri gen. nov. et sp. nov. is erected. The lack of morphological data from the flower itself and the fact that comparable pollen tetrads can be produced by a number of modern families, however, prevent an assignment of the new taxon to any known angiosperm family., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Alexander von Humboldt-Stiftung http://dx.doi.org/10.13039/100005156

Published
2020

28. Detrital zircon U–Pb ages, Hf isotopic constraints, and trace element analysis of Upper Cretaceous–Neogene sedimentary units in the Western Nepal Himalaya: Implications for provenance changes and India–Asia collision.

Author

Baral, Upendra, Lin, Ding, Chamlagain, Deepak, Qasim, Muhammad, Paudayal, Khum N., Neupane, Bhupati, and Tyrrell, S.

Subjects
ZIRCONIUM isotopes, URANIUM-lead dating, TRACE element analysis, GEOLOGICAL formations, NEOGENE Period
Abstract

The present study integrates detrital zircon U–Pb–Hf isotopic analysis from 13 sandstone samples from an Upper Cretaceous–Miocene sedimentary sequence in Nepal Himalaya to determine their provenance. These sequences constrain a shifting of provenance from south to north. The U–Pb ages from Upper Cretaceous–Palaeocene strata (Amile Formation) mainly cluster between ~1,860 and 1,400 Ma with a peak at ~1,630 Ma and an absence of grains younger than the Palaeoproterozoic (1,400 Ma) age. The detritus yielded positive detrital zircon ƐHf (t) values (as high as +10). However, the detrital zircon U–Pb ages from Eocene–Miocene sequence cluster at ~500–650, ~700–900, ~1,600–1,850, and ~2,500 Ma, and in addition, they have both positive and negative ƐHf (t) values (+11 to −25). This finding further elucidates that the detritus in the Amile Formation was entirely sourced from India, which changed following the time of the Bhainskati Formation deposition, to a mixture of both Asian and Indian affinities (the Himalayan region). This change in source region marks the possible time of the India–Asia collision during this transition phase, that is, Late Palaeocene–Earliest Eocene. [ABSTRACT FROM AUTHOR]

Published
2019
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29. Fig leaf from the Middle Siwalik sediments of eastern Nepal with implication on biogeography and palaeoclimate

Author

Adhikari, Purushottam, Bhatia, Harshita, Khatri, Dhan Bahadur, Sadananda, Srivastava, Gaurav, Mehrotra, R. C., and Paudayal, Khum N.

Abstract

The Siwalik flora is important in understanding the orogeny of the Himalayas and the resulting climate change. Though the fossil records from the eastern Himalayan Siwalik of Nepal are sparse, we report a fossil leaf impression/ compression of Ficus precuneaLakhanpal from the Middle Siwalik (upper Miocene–lower Pliocene) sediments of eastern Nepal. The characteristic leaf venation pattern and morphological details suggest its strong affinity with the extant species of F. semicordataBuch.-Ham. ex Sm. The fossil assemblage indicates the presence of seasonal forests during the depositional period in the region.

Published
2024
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41. Reconstruction of paleovegetation and paleoclimate in the Early and Middle Eocene, Hainan Island, China.

Author

Yi-Feng Yao, Bera, Subir, Ferguson, David K., Mosbrugger, Volker, Paudayal, Khum N., Jian-Hua Jin, and Cheng-Sen Li

Subjects
CLIMATE change, TEMPERATE climate, EOCENE stratigraphic geology, CLIMATOLOGY
Abstract

The Early–Middle Eocene palynoflora and paleoclimate of Changchang Basin, Hainan Island, South China, is described in the present paper and is compared with that of the Middle–Late Eocene, Hunchun City, Jilin Province, North China. The nearest living relatives (NLRs) of the recovered palynotaxa suggest a subtropical evergreen or deciduous broad-leaved forest at the center of the basin but a temperate evergreen or deciduous broad-leaved forest and needle-leaved forest growing in the peripheral part of the basin. Based on the climatic preferences of the NLRs, the climate in the Changchang Basin during the Early–Middle Eocene was warm and humid subtropical with a mean annual temperature of 14.2–19.8°C, a mean temperature of the warmest month of 22.5–29.1°C, a mean temperature of the coldest month of 1.7–11.9°C, a difference of temperature between coldest and warmest months of 12.1–24.6°C, a mean annual precipitation of 784.7–1,113.3 mm, a mean maximum monthly precipitation of 141.5–268.1 mm and a mean minimum monthly precipitation of 6.9–14.1 mm. A comparison of the palynoflora and paleoclimate between the Changchang Basin and Hunchun City, suggests essentially a similar climate in South and North China during Eocene time in contrast to the oceanic tropical climate in South China and cool dry temperate climate in North China as at present. [ABSTRACT FROM AUTHOR]

Published
2009
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