The oldest fossil of Duabanga from Kutch, western India

Shukla & Mehrotra – Deccan Duabangoxylon (Lythraceae) IAWA Journal 38 (4), 2017: 553–560

553

The oldest fossil of Duabanga from Kutch, western India Anumeha Shukla* and R.C. Mehrotra Birbal Sahni Institute of Palaeosciences, 53 University road, Lucknow-226007, India *Corresponding author; email: [email protected]

Abstract

The systematics of a fossil wood assigned to Duabangoxylon (family Lythraceae) is described from the Deccan Intertrappean beds of Kutch, Gujarat, western India considered to be late Maastrichtian to early Danian in age. This fossil is the oldest record of Duabanga as its previous records are not older than Eocene. As the intertrappean flora of Kutch is poorly known, the present fossil not only enriches this flora but also helps in the reconstruction of palaeoclimate. Keywords: Fossil wood, Lythraceae, Deccan traps, late Maastrichtian to early Danian, Kutch. [In the online version of this paper Figure 2 is reproduced in colour.] Introduction

The Deccan Intertrappean beds represent the most significant geological feature of the Indian subcontinent that occurred between late Cretaceous–early Palaeogene (K-Pg) (Smith et al. 2015). The moving Indian plate, from south of the equator to the north after its separation from the rest of Gondwana, led to the massive volcanism on the Indian landmass (Chatterjee et al. 2013), which might be responsible for the total disappearance of dinosaurs and decline of other biota (Sheehan et al. 2000; Pearson et al. 2001; Wilf et al. 2003; Keller et al. 2009a,b) existing at that time. Radiometric dating and magnetostratigraphic studies (Keller et al. 2009a,b; Chenet et al. 2009) suggest that the volcanism extended from c. 67.5 ±1 to 63 Ma, with a bulk eruption at 65±1 Ma (Chenet et al. 2009). The Deccan traps are spread over the parts of the Indian states of Gujarat, Maharashtra, Madhya Pradesh, Andhra Pradesh and Karnataka and intertrappean beds were deposited between two lava flows during quiescent intervals and are of great interest for palaeontologists and palaeobotanists as they contain animal and plant micro- and megaremains which can be interpreted in terms of palaeoclimatology, palaeoecology and age of the sediments. The fossil biota retrieved from the Deccan Intertrappean beds range from algae to angiosperms (Srivastava 2011). While most of the previously described fossils have been from central India (Madhya Pradesh and Maharashtra), only a few elements are reported from western India (Lakhanpal et al. 1976; Srivastava 1991; Srivastava & Guleria 2005). The Kutch intertrappean beds have been explored for micro fossils (Bajpai et al. 1993; Bhandari & Colin 1999; Whatley & Bajpai 2000; Bajpai & Whatley 2001; Dogra © International Association of Wood Anatomists, 2017 Published by Koninklijke Brill NV, Leiden

DOI 10.1163/22941932-20170180

554

IAWA Journal 38 (4), 2017

et al. 2004) and plant megaremains (Guleria & Srivastava 2001). The fossil woods of five taxa were described systematically from near Anjar, Kutch district (Guleria & Srivastava 2001). Keeping in mind the poor megafossil record from there, a field trip was undertaken to collect more plant fossils. One of the woods from this collection being described here is new to the fossil flora and extends our knowledge of the rich assemblage of Deccan woods, recently reviewed by Wheeler et al. (2017). Material and Methods

The fossil material was collected from the intertrappean bed number III from the Vidi village (23° 4 ' 50" N; 70° 30 " E), south of Anjar, Kutch district, Gujarat (Fig.1). This particular bed was previously explored for both plant and animal remains by many workers (Ghevariya 1988; Ghevariya & Srikarni 1990; Bajpai et al. 1993; Guleria & Srivastava 2001). The fossil wood was cut into thin sections, i.e. transverse, tangential longitudinal and radial longitudinal for the anatomical study. Each section was polished and mounted

Figure 1. Map showing the fossil locality (marked by a star) (after Ghevariya 1988).

Shukla & Mehrotra – Deccan Duabangoxylon (Lythraceae)

555

in Canada balsam on a glass slide. It was prepared using the standard techniques for petrographic thin sections (Haas & Rowe 1999). These sections were studied with light microscopy and photographed using a Leica DFC 290 digital camera. The fossil wood was compared not only with extant taxa by examining available wood slides at the xylarium of the Birbal Sahni Institute of Palaeosciences (BSIP), Lucknow, but also with published literature and the InsideWood database (http://insidewood.lib. ncsu.edu/; Wheeler 2011). While describing the fossil, we have followed the terminology of the IAWA Committee (1989). The figured specimen is deposited in the museum of the Birbal Sahni Institute of Palaeosciences, Lucknow. Systematic description

Family: Lythraceae Genus: Duabangoxylon Prakash & Awasthi (1970) Species: Duabangoxylon indicum (Navale) Awasthi (1981) (Fig. 2) Description – Wood diffuse porous. Growth rings present, marked by zones of dark coloured denser fibres. Vessels small to large, tangential diameter range 66–267 µm, mean 133 µm, solitary (about 70%) and in radial multiples of 2–5 (about 30%), occasionally in tangential pairs or clusters, usually round to oval, evenly distributed, 11–20 per sq.mm; tyloses present; vessel elements with oblique to horizontal ends, 98–471 µm in length, mean c. 231 µm; perforation plates simple; intervessel pits bordered, alternate, vestured, 9–12 µm in diameter; vessel-parenchyma pits similar to intervessel pits; vessel-ray pits with reduced borders, pits appearing both vertical and horizontal. Axial parenchyma vasicentric and aliform; cells up to 8 per parenchyma strand, 30–60 µm in diameter and 48–154 µm in height. Rays predominantly uniseriate, occasionally biseriate, 10–12 per mm, homo- to heterocellular, 16–47 µm in width and 2–14 cells or 133–593 µm in height; procumbent cells 60–73 µm in radial length and 16–43 µm in tangential height; upright cells in 1 to 3 rows, 15–36 µm in radial length and 64–83 µm in tangential height; prismatic crystals rare. Fibres aligned in radial rows, angular in cross section, moderately thick-walled, non-septate, 16–30 µm in diameter. Figured specimen – No. BSIP41078. Locality – Near Anjar, Kutch district, Gujarat. Horizon – Deccan intertrappean beds. Age – Late Maastrichtian to early Danian. Affinities – The characteristic features of the fossil wood are: medium to large vessels, vasicentric to aliform axial parenchyma, vestured intervessel pits, vessel-ray pits with reduced borders, predominantly uniseriate, homo- to heterocellular rays and nonseptate fibres. All these features collectively indicate its affinity with the extant woods of the families Combretaceae, Lythraceae, Myrtaceae and Crypteroniaceae (Pearson & Brown 1932; Metcalfe & Chalk 1950; Kribs 1959; Miles 1978; Kazmi 1982; Ilic 1991; Lemmens et al. 1995; Wheeler 2011; http://insidewood.lib.ncsu.edu/ ). After a detailed comparison with the modern genera of the family Lythraceae the present fossil wood shows its closest similarity with the genus Duabanga Buch.-Ham. The other anatomically close genera of the family, i.e. Lagerstroemia and Sonneratia can


50 µm

100 µm

100 µm

100 µm

200 µm

50 µm

500 µm

50 µm

200 µm

556

Figure 2. Duabangoxylon indicum (Navale) Awasthi (1981) – A: Cross section showing diffuse porous wood and paratracheal parenchyma. – B: Enlarged cross section showing vasicentric and aliform to aliform-confluent axial parenchyma. – C: Showing vessel parenchyma pits (boundary of parenchyma cells marked by arrows). – D: Tangential longitudinal section showing predominantly uniseriate rays. – E: Showing structure of rays. – F: Showing vessel ray pits. – G: Radial longitudinal section showing heterocellular rays. – H: Showing vestured intervessel pits. – I. Showing a prismatic crystal in ray cell (marked by arrow).


557

be separated easily in having septate fibres. Moreover, the wood of Sonneratia either lacks parenchyma or has scanty paratracheal parenchyma. The woods of Anogeissus and Terminalia of the Combretaceae, though showing some similarities with the fossil, can easily be separated by their vessel-ray pits with distinct borders. Moreover, Anogeissus also possesses septate fibers in contrast to non-septate fibers in the fossil. Most extant genera of Myrtaceae can easily be distinguished in having distinct vasicentric tracheids (Purkayastha et al. 1982). Crypteronia of the family Crypteroniaceae is similar to the present fossil but differs in having diffuse-in-aggregates parenchyma (Kazmi 1982). As the fossil shows its closest resemblance with Duabanga, a further comparison was carried out with its two extant species, D. grandiflora and D. moluccana. Our fossil shows close resemblance with both species (http://insidewood.lib.ncsu. edu/). As the latter species is native to Indonesia and surrounding areas, the chances of nearest comparable species are more with D. grandiflora, which is native to the Indian subcontinent. Duabanga, a small genus from Southeast Asia, was earlier placed in the family Sonneratiaceae. Later, it has been reclassified and put in the monotypic subfamily Duabangoideae of the family Lythraceae (APG IV). The fossil wood resembling Duabanga is placed in the organ genus Duabangoxylon Prakash & Awasthi (1970) and so far three of its species have been described, i.e. D. biferium Gottwald (1994) from the Tertiary of Myanmar, D. indicum (Navale) Awasthi (1981) from the late Mio-Pliocene of Puducherry (South India) and D. tertiarum Prakash & Awasthi (1970) from the late Miocene-Pliocene of North-east India (Mehrotra & Mandaokar 1998). Later on, D. indicum was also recorded by Awasthi & Prasad (1988) from the Siwalik sediments of Kalagargh, Uttarakhand (middle Miocene). We have compared our fossil with the known fossil species of Duabanga and the present fossil is found similar to Duabangoxylon indicum (Navale) Awasthi. The other two described fossils, D. tertiarum Prakash & Awasthi and D. biferium Gottwald, are different in having taller rays and septate fibres, respectively. As septate fibres are not found in Duabanga, the affinities of D. biferium appear doubtful. Considering the similarity of the present fossil with the already known species of Duabangoxylon indicum, we assign our fossil to the same species. Little et al. (2004) described a leaf resembling Duabanga from the middle Eocene Princeton chert of British Columbia, Canada. As all these described fossils are not older than Eocene, the present fossil from the Deccan intertrappean beds becomes the oldest record of Duabanga. Discussion

Wynne (1872) first described the occurrence of Deccan intertrappean beds in Kutch, Gujarat. After that, many workers explored the age and biota present in the sediments. Bajpai et al. (1993), Bhandari & Colin (1999) and Whatley & Bajpai (2000) recorded ornithoid eggshells, limnic ostracods and nonmarine ostracods, respectively, from the intertrappean beds of Kutch exposed near Anjar in the Kutch district. Dogra et al. (2004) recorded a palynofloral assemblage from the Anjar intertrappean beds and assigned a Maastrichtian age to them. Apart from these palaeontological records, a

558


few plant megaremains were also retrieved from these beds, i.e. the permineralised woods of extant genera, namely Homalium (Salicaceae), Hydnocarpus (Achariaceae), Stemonurus (Icacinaceae), Bischofia (Phyllanthaceae), and Mallotus (Euphorbiaceae) (Guleria & Srivastava 2001; Wheeler et al. 2017). All these genera are high humidity elements mainly distributed in wet evergreen to semi-evergreen forests of the Indian subcontinent at present. The present fossil resembles modern Duabanga grandiflora, which is an evergreen tree found up to an elevation of 1500 m asl (above sea level) in the open forests adjacent to the valleys and river banks. One of the previously described elements, i.e. Mallotus javanica, is also found near fresh-water swamps. Biogeographically, Duabanga is distributed from eastern India to South China and the Malaysian Peninsula. The palaeoposition (~17° S) of the fossil locality during the time of deposition at ~65 Ma (Chatterjee et al. 2013) also supports our conclusion based on the retrieved fossil from the Deccan intertrappean beds of Kutch. As the present fossil wood is the oldest record of the genus Duabanga, it provides a clue about the Gondwanic origin of the genus which then spread over the Southeast Asian countries after the land connections were established during the Eocene and afterwards. Acknowledgements The authors are thankful to Prof. Sunil Bajpai, the Director of the Birbal Sahni Institute of Palaeosciences (BSIP), Lucknow, India for providing the infrastructure and permission to publish this work. They also express their gratitude to Prof. Baas and anonymous reviewers for their constructive suggestions.

References APG – Angiosperm Phylogeny Group. 2016. “An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV”. Bot. J. Linn. Soc. 181: 1–20. Awasthi N. 1981. Reinvestigation of Sapindoxylon indicum Navale from the Cuddalore Series near Pondicherry. Palaeobotanist 27: 161–163. Awasthi N, Prasad M. 1988. Occurrence of Duabanga in the Siwalik sediments. Geophytol. 17: 292–294. Bajpai S, Sahni A, Srinivasan S. 1993. Ornithoid eggshells from Deccan intertappean beds near Anjar (Kachchh), Western India. Cur. Sci. 64: 42–45. Bajpai S, Whatley RC. 2001. Late Cretaceous non-marine ostracods from the Deccan Intertrappean beds, Kora (Western Kachchh, India). Rev. Españ. Micropal. 33: 91–111. Bhandari A, Colin JP. 1999. Ostracodes limniques des sédiments Intertrappéens (Maastrichtian Terminal-Paléocène Basal) de la région d’Anjar (Kachchh, État. De Gujarat), Inde: Systématique, Paléoécologie et Affinités Paléobiogéographiques. Rev. de Micropal. 42: 3–20. Chatterjee S, Goswami A, Scotese CR. 2013. The longest voyage: Tectonic, magmatic, and palaeoclimatic evolution of the Indian plate during its northward flight from Gondwana to Asia. Gond. Res. 23: 238–267. Chenet AL, Courtillot V, Fluteau F, Gérard M, Quidelleur X, Khadri SFR, Subbarao KV, Thordarson T. 2009. Determination of rapid Deccan eruptions across the Cretaceous-Tertiary boundary using paleomagnetic secular variation: 2. Constraints from analysis of eight new sections and synthesis for a 3500-m-thick composite section. J. Geophys. Res. 114: B06103.


559

Dogra NN, Singh RY, Singh RY. 2004. Palynological assemblage from the Anjar intertrappeans, Kutch district, Gujarat: Age implications. Curr. Sci. 86: 1596–1597. Ghevariya ZG. 1988. Intertrappean dinosaurian fossils from Anjar area, Kachchh District, Gujarat. Curr. Sci. 57: 248–251. Ghevariya ZG, Srikarni C. 1990. Anjar Formation, its fossil and their bering on the extinctions of dinosaurs. In: Sahni A & Jolly A (eds.), Cretaceous event stratigraphy and the correlation of the Indian nonmarine strata: 106–109. Chandigarh. Gottwald HPJ. 1994. Tertiäre Kieselhölzer aus dem Chindwinn-Bassin im nordwestlichen Myanmar (Birma). Docum. Nat. 86: 90. Guleria JS, Srivastava R. 2001. Fossil dicotyledonous woods from the Deccan Intertrappean beds of Kachchh, Gujarat, western India. Palaeontography B257: 17–33. Hass H, Rowe NP. 1999. Thin sections and wafering. In: Jones TP, Rowe NP (eds.), Fossil plants and spores: modern techniques: 76–81. Geological Society, London. IAWA Committee. 1989. IAWA List of microscopic features for hardwood identification. IAWA Bull. n s. 10: 219–332. Ilic J. 1991. CSIRO atlas of hardwoods. Springer, Berlin. Kazmi SMH. 1982. Family Sonneratiaceae. In: Purkayastha SK (ed.), Indian woods 4: 39–42. The Controller of Publications, Delhi. Keller G, Adatte T, Bajpai S, Khosla A, Sharma R, Widdowson M, Khosla SC, Mohabey DM, Gertsch B, Sahni A. 2009 a. K-T transition in Deccan Traps of central India marks major marine seaway across India. Earth Planet. Sci. Lett. 282: 10–23. Keller G, Sahni A, Bajpai S. 2009 b. Deccan volcanism, the KT mass extinction and dinosaurs. J. Biosci. 34: 709–728. Kribs DA. 1959. Commercial foreign woods on the American market. Pennsylvania State University, Pennsylvania. Lakhanpal RN, Maheshwari HK, Awasthi N. 1976. A catalogue of Indian fossil plants. Birbal Sahni Institute of Palaeobotany, Lucknow. Lemmens RHMJ, Soerianegara I, Wong WC. 1995. Plant resources of South-East Asia (PROSEA) 5 (2). Timber trees: Minor commercial timbers. Backhuys, Leiden. Little SA, Stockey RA, Eating RC. 2004. Duabanga-like leaves from the middle Eocene Princeton chert and comparative leaf histology of Lythraceae sensu lato. Amer. J. Bot. 91: 1126–1139. Mehrotra RC, Mandaokar BD. 1998. Fossil wood resembling Duabanga from Tipam Sandstone of Makum Coalfield, Assam. Geophytology 26: 99–101. Metcalfe CR, Chalk L. 1950. Anatomy of the dicotyledons, 1 & 2. Clarendon Press, Oxford, United Kingdom. Miles A. 1978. Photomicrographs of world woods. Building Res. Establ. Rep., London. Pearson DA, Schaefer T, Johnson KR, Nichols DJ. 2001. Palynologically calibrated vertebrate record from North Dakota consistent with abrupt dinosaur extinction at the CretaceousTertiary boundary. Geology 29: 39– 42. Pearson RS, Brown HP. 1932. Commercial timbers of India, 1 & 2. Govt. India Central Publ. Br., Calcutta. Prakash U, Awasthi N. 1970. Fossil woods from the Tertiary of eastern India. 1. Palaeobotanist 18: 32– 44. Purkayastha SK, Shahi R, Taneja K. 1982. Family Myrtaceae. In: Purkayastha SK (ed.), Indian woods 4: 1–18. The Controller of Publications, Delhi.

560


Sheehan PM, Fastovsky DE, Barreto C, Hoffmann RG. 2000. Dinosaur abundance was not declining in a “3 m gap” at the top of the Hell Creek Formation, Montana and North Dakota. Geology 28: 523–526. Smith SY, Manchester SR, Samant B, Mohabey DM, Wheeler EA, Baas P, Kapgate D, Srivastava R, Sheldon ND. 2015. Integrating paleobotanical, paleosol, and stratigraphic data to study critical transitions: a case study from the Late Cretaceous-Paleocene of India. Paleontol. Soc. Pap. 21: 137–166. Srivastava R. 1991. A catalogue of fossil plants from India. 4. Cenozoic (Tertiary) megafossils. Birbal Sahni Institute of Palaeobotany, Lucknow. Srivastava R. 2011. Indian Upper Cretaceous-Tertiary flora before collision of Indian plate: A reappraisal of central and western Indian flora. Mem. Geol. Soc. India 77: 281–292. Srivastava R, Guleria JS. 2005. A catalogue of Cenozoic (Tertiary) plant megafossils from India (1989–2005). Birbal Sahni Institute of Palaeobotany, Lucknow. Whatley R, Bajpai S. 2000. A new fauna of Late Cretaceous non-marine Ostracoda from the Deccan intertrappean beds of Lakshmipur, Kachchh (Kutch) district, Gujarat, western India. Rev. Españ. Micropal. 32: 385– 409. Wheeler EA. 2011. InsideWood – a web resource for hardwood anatomy. IAWA J. 32: 199– 211. Wheeler EA, Srivastava R, Manchester SR, Baas P. 2017. Surprisingly modern. Latest Cretaceous–earliest Paleocene woods of India. IAWA J. 38: 456–542. Wilf P, Johnson KR, Huber BT. 2003. Correlated terrestrial and marine evidence for global climate changes before mass extinction at the Cretaceous–Paleogene boundary. PNAS 100: 599– 604. Wynne AB. 1872. Memoirs on the geology of Kutch to accompany a map compiled by A.B. Wynne and F. Fedden during the season 1867–1868 and 1868–1869. Mem. Geol. Surv. India 9: 1–293. Accepted: 31 January 2017