JOURNAL GEOLOGICAL SOCIETY OF INDIAVol.85, April 2015, pp.457-462

0016-7622/2015-85-4-457/$ 1.00 © GEOL. SOC. INDIA

Megaloolithus Dinosaur Nest from the Lameta Formation of SalbardiArea, Districts Amravati, Maharashtra and Betul, Madhya Pradesh

ASHOK K. SRIVASTAVA and RUPESH S. MANKAR

P.G. Department of Geology, SGB Amravati University, Amravati - 444 602Email: ashokamt2000@ hotmail.com

Abstract: The present paper contributes the new locality of a nest of sauropod dinosaur from fluvial sediments of theLameta Formation of Salbardi area. On the basis of shape, size and microstructures of the shell, it is identified asMegaloolithus. The new locality is away from the known nesting sites of dinosaurs already been reported i.e., Nagpurand Jabalpur, therefore bears significance in reconstruction of palaeogeographic boundary of dinosaurs-nesting sites.

Keywords: Megaloolithus, Nest and eggs, Salbardi, Sauropod, Lameta.

INTRODUCTION

In India, the study of dinosaur eggs and nests goes backonly three decades ago. The maiden discovery of eggs andnests is from limestone quarry of the Lameta sediments fromBaliadeo village, near Balasinor, Kheda district, Gujarat(Mohabey, 1983). However, fragments of eggshells fromBara Simla hill area of Jabalpur were reported earlier (Sahniand Gupta, 1982). After these initial reports, many sites ofeggs, nests and eggshells debris were reported from all overIndia in the time span of about thirty years. The localitiesare mostly restricted to the Lameta successions exposed atGujarat, Madhya Pradesh and Maharashtra. Mohabey (1998,2000) has made an attempt to review the eggs and nests ofdinosaurs from the upper Cretaceous Lameta sediments ofcentral and western India to understand their community,structures, nesting habit and extinction.

The presently identified locality is a new addition fromwhich solitary nest has been recorded from calcretizedsandstone horizon of Lameta succession. An attempt is beingmade to describe their morphology and classification.Discussions have also been made to interpret the conditionof depositional environment in which the eggs were laid.

GEOLOGY AND STRATIGRAPHY

The Lameta sediments occupy an east-west elongatednarrow patch at Salbardi area (lat. 21°25'15" N: long.78°00'00" E), lying at the boundary of districts Amravati,Maharashtra and Betul, Madhya Pradesh (Fig. 1). Thesesediments along with the Gondwana are exposed as tectonicinliers in regionally exposed Deccan basalt. The Gondwana

sediments are mostly represented by arenaceous rockscorelatable with the Jabalpur Formation of early Cretaceousage as evident by pteridophytic and gymnosperm leafremains (Srivastava et al., 1999, 2007). The Lametasediments are thinly to thickly bedded units which aremainly represented by arenaceous, argillaceous and calc-marl sediments overlying disconformably on the Gondwanarocks. The basement rock is quartz-feldspathic gneiss ofArchaean age which is highly disturbed and frequentlyintruded by dolerite dykes. The peripheral area is basaltictrap, occurring in the form of minor hillocks of hard, massiveto vesicular basalts or weathered in low lying areas. Thetopmost layer is alluvium or dark coloured soil derived fromweathering of the basalt (Table 1).

Table 1. Regional stratigraphic set-up of the area

Age Stratigraphic units Rock types

Quaternary Soil and alluvium

- - - - - - - - - - - - - - - - -Unconformity - - - - - - - - - - - - - - - - -

L. Cretaceous Deccan Trap Grayish black, hard andto Eocene compact, non porphyritic

and porphyritic basalts

- - - - - - - - - - - - - - - - -Unconformity - - - - - - - - - - - - - - - - -

L. Cretaceous Lameta Sandstone, claystone,mudstone and limestone

- - - - - - - - - - - - - - - - - Disconformities - - - - - - - - - - - - - - - -

E. Cretaceous Upper Gondwana Sandstone, siltstone,(Jabalpur Formation) conglomerate, clay and

mudstone

- - - - - - - - - - - - - - - - -Unconformity - - - - - - - - - - - - - - - - -

Archaean Quartz-feldspathic gneisswith dolerite intrusions

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458 ASHOK K. SRIVASTAVA AND RUPESH S. MANKAR

A good section of Lameta sediments attaining a heightof about 35m is exposed at the bank of Maru river. Thisriver-cut section is constituted together by arenaceous,argillaceous and calcareous sediments (Fig. 2). Thearenaceous unit is dark brown and medium green, hard andcompact, medium to fine grained sandstones withferruginous and calcareous cementing materials. The bedsranging in thickness from 2-3m are interbedded with 1-2mthick, dark reddish brown and greenish brown clay horizons.This entire unit constitutes 9m column in the lower part ofthe succession. Overlying 18m succession consists ofcalcrete, clay and sandstone horizons. Calcretes are recordedat two stratigraphic levels, of which, the lower overlainsgreenish sandstone and is light gray in colour having

Nodular limestone is ca one-meter thick, bluish gray, hardand compact rock which overlies 3m chertified limestoneshowing intense silicification. Intraformational brecciatedlimestone is the topmost unit which is represented by reddishbrown, micritic limestone having clasts of nodular limestoneand chertified limestone.

EGGSHELLS SYSTEMATIC

Oofamily MEGALOOLITHIDAE Zhao, 1979Oogenus MEGALOOLITHUS Vianey-Liaud et al., 1994

Diagnosis: Dinosauroid-spherulithic basic type;tubospherulithic morphotype; tubocanaliculate pore system;

Fig.1. Location map of Lameta succession exposed in central and western India (left) and geological map of the study area (right).

Fig.2. Litholog of the Lameta succession exposed at the study area; arrow denotes the eggbearing horizon.

abundant vertical to inclined, cylindricalroot calcrete. It is overlain sharply bylight green calcareous sandstone. Theoverlying 3m succession is again lightbrown calcrete but nodular in naturehaving clasts of greenish sandstone,nodular limestone and basalt. It overlies7m thick column of greenish gray anddark reddish brown clays withinterbeddings of 60-90cm thick greensandstone beds. The upper 5m horizonis represented by light bluish gray,medium to coarse grained sandstonewith ferruginous nodules, of which, thetop one meter egg-bearing lithounit iscalcretized. Chertification of this entirearenaceous lithounit is very distinct inthe form of lenses, discrete pockets andirregular veins.

The rest of the column, constitutingupper 8m is dominantly calcareous innature represented by nodular lime-stone, chertified limestone and intra-formational brecciated limestone.

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Megaloolithus DINOSAUR NEST FROM THE LAMETA FORMATION OF SALBARDI AREA, MAHARASHTRA 459

compactituberculate ornamentation. Spherical to sub-spherical eggs ranging from 120 to 200mm having eggshellthickness of 1.5-3.0mm.

Material: Incomplete eggs and fragments (Fieldspecimen preserved in the rock; thin sections (SDE 1-4)and chips of egg shell (SDE-5)).

Locality and Horizons: Lameta Formation of Salbardiarea, districts Amravati, Maharashtra and Betul, MadhyaPradesh. Nesting site lies towards north of Salbardi villageat a distance of about 1.5km on pedestal track to Ghorpendvillage, precisely, at the spot having GPS coordinates of lat.21025’827'’ N: long.78000’320'’ E which falls in Betuldistrict, Madhya Pradesh. The eggs are well preserved inone-meter thick, grayish yellow, medium to coarse grainedcalcretized sandstone. Petrographically, the rock containssub-angular to sub-rounded, medium to coarse grains ofquartz. The entire rock shows calcification in which thecarbonate is non-ferroan micritie (Fig. 3).

Occurrence: A clutch of incomplete eggs comprises ofone eggshell almost completely in circular outline, two

broken nearly half circular and one small fragment exhibitingirregular pattern of egg nest (Fig. 4a,b).

Diagnosis: Megaloolithus with spherical eggs; diameter150-152mm; shell thickness 2 to 2.3mm; shell units areslenderical, H/W ratio = 4.

Description: Upper surface of the calcretized sandstonebed showing preservations of four spherical eggs of almostsame diameter i.e., 150-152mm, of which, one showscomplete circular outline, whereas, the other three areincomplete (Fig. 4a,b). The shell thickness ranges between2 to 2.3mm having H/W ratio of 4. The outer surface of theeggs reveal compactituberculate ornamentation representedby densely packed nodes of sub-circular and circular shape(Fig. 5a,b). The shell units are discrete, short and slenderwith acute dome-shaped tops which are mostly straight butoccasionally curved (Fig. 6a,b). It is growing from singlemammillae (spherolith), however, extra growth centers andchaotically grown, short shell units are also noticed whichindicate the abnormality in the process of formation ofeggs. The growth lines are distinct and arch in shapethroughout the entire shell unit, however, at a few places,they may be fused on the upper part showing contourpattern. The pore canals are distinct, narrow, short andirregular showing tubocanaliculate pattern (Fig. 7).

Comparison: Mohabey (1998, 2000) made a detailedcomparative study of shape, size, ornamentation, shellthickness, height and width (H/W) ratio and pore system ofthe dinosaur’s eggs in India and established eight oospeciesof Megaloolithidae oofamily. Accordingly, the presentlyreported eggs are identified to be the member ofMegaloolithus oogenus. Further subdivision of the same intooospecies is difficult due to the deviations of its certaincharacteristic properties from those of the eight oospeciesproposed by Mohabey (1998, 2000). It has been noted that

Fig.3. Microphotograph showing calcretized sandstone havingsubangular to subrounded grains of quartz.

Fig.4. (a) Photograph showing the upper surface of bed having preservation of the eggs; (b) reconstruction of the nest pattern; dottedline shows the predicted extension.

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460 ASHOK K. SRIVASTAVA AND RUPESH S. MANKAR

the shape, size, ornamentation and pore system of the presenteggs are comparable with M. rahiolienesis (spherical; 125-160mm; compactituber; tubocanaliculate); M.dhoridungriensis (spherical; 140-180 mm; compactituber;tubocanaliculate) and M. balasinorensis (spherical; 140-180mm; compactituber; tubocanaliculate). Similarly, thespherolith thickness is comparable with M. khempuensis

(2.36-2.50mm) and M. dhoridungriensis (2.26-2.36mm)whereas, height and width ratio matches with M. rahioliensis(4). The microscopic characteristics of shell unit i.e., extra-growth centers and the chaotically grown giant and dwarfshell units are similar to the M. megadermus, however,differs largely in other diagnostic characteristics i.e.,spheroidal shape, 4-4.80mm spherolith thickness and

Fig.5. (a) Close-up of eggshell surface in the field showing compactiturculate pattern; (b) enlargement of the same showing subcircularto circular nodes.

Fig.6. (a) Slender, elongated shell units having arch shape growth lines; (b) line diagram showing shape and pattern of shell units.

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Megaloolithus DINOSAUR NEST FROM THE LAMETA FORMATION OF SALBARDI AREA, MAHARASHTRA 461

9.60 H/W. Limited numbers of eggs and their entirepreservation in the bed rock posses certain limitations forthe detail study of the present specimen, therefore, theauthors propose the identification up to oogenus level onlyi.e., Megaloolithus.

DISCUSSION AND CONCLUSION

Various schemes of classification for the Indian dinosaurseggshells have been proposed which are mainly based ongeneral morphology including shape and size, ratio of heightto width and microstructures of the eggshells (Jain and Sahni,1985; Vianey-Liaud et al., 1987; Bajpai et al., 1993; Khoslaand Sahni, 1995; Mohabey, 1998; 2000). Mohabey (1998,2000) has proposed systematics of Indian Maastrichtian

dinosaur’s eggs and categorized them in two families viz.,Megaloolithidae and Elongatoolithidae; which are furthersubdivided into various oogenera on the basis of shapeand microstructures. Preservational aspects of the presentspecimen allow to study only the shape, size and shellsthickness i.e., spherical in shape having a diameter of150-152mm and 2-2.3mm of shell thickness. The shell unitis elongated showing irregular growth and arch shapegrowth lines. On the basis of spherical shape, compacti-tuberculate ornamentation, tubospherulitic shell structureand tubocanaliculate porecanals, the present eggs areconsidered as Megaloolithus of Megaloolithidae oofamily(Vianey-Liaud et al., 1994; Mohabey, 1998, 2000). Furtherclassification up to oospecies level is difficult because oflimitations in number of eggs and their morphologicalinvestigation in the field due to solitary exposure of a nesthaving incomplete preservations of egg shells.

Till date, the authors have recorded only one nest in thearea. However, it bears significance in a way that this newsite is geographically much away from the earlier knownlocalities of the Lameta sediments in Nagpur, Maharashtraand Jabalpur, Madhya Pradesh (Jain and Sahni, 1985;Mohabey, 1990, 2000). Fragments of bones viz., ulna hasalso been reported from the same area (Srivastava andMankar, 2013a). It necessitates for reconsideration andrevision of the existing palaeogeography of dinosaurs nestingsites in India. The Lameta succession exposed in this areaincluding eggs-bearing lithounit has been studied in detailfor its lithofacies architecture, depositional environment andpetrological details including diagenetic history (Srivastavaand Mankar, 2010; 2012; 2013b). On the basis of lithologicalarchitecture, the succession is interpreted to be a product ofpoint bar, channel and flood plain environments of semi-arid fluvial setting. The egg-bearing horizon is calcretizedsandstone which was deposited probably at the over bankwhich was also subjected to pedogenic activity during thelater phase.

Acknowledgement: Authors are thankful to UGC, NewDelhi for providing financial support in the form of a MajorResearch Project (F. 40/295/2011 (SR)) awarded to one ofthe author (AKS) and also to CSIR, New Delhi as SRF (F-09/855 (0003)/2012) to second author (RSM).

References

BAJPAI, S., SAHNI, A. and SRINIVASAN, S. (1993) Ornithoid eggshellsfrom Deccan Intertrappean beds near Anjar (Kachchh), WesternIndia. Curr. Sci., v.64(1), pp.42-45.

JAIN, S.L. and SAHNI , A. (1985) Dinosaurian egg shell fragments

from the Lameta formation at Pisdura, Chandrapur district,Maharashtra. Geosci. Jour. (India), v. 6, no. 2, pp. 211-220.

KHOSLA, A. and SAHNI, A. (1995) Parataxonomic classification of

Late Cretaceous dinosaur eggshells from India. Jour. Pal. Soc.

Fig.7. Photograph showing a slender shell unit (SU) having archshape growth lines and distinct pore canal (PU).

JOUR.GEOL.SOC.INDIA, VOL.85, APRIL 2015

462 ASHOK K. SRIVASTAVA AND RUPESH S. MANKAR

India, v., 40, pp. 87-102.MOHABEY, D.M. (1983) Note on occurrence of dinosaurian fossil

eggs from infratrappean limestone in Kheda district, Gujarat.Curr. Sci., v. 52, no. 24, pp. 1194.

MOHABEY, D.M. (1990) Dinosaur eggs from Lameta Formation ofWestern and Central India: their occurrence and nestingbehavior. In: A. Sahni and A. Jolly (Eds.), Cretaceous EventStratigraphy and Correlation of the Indian Non-marine Strata,Panjab University, Chandigarh, pp. 18-21.

MOHABEY, D.M. (1998) Systematics of Indian Upper Cretaceousdinosaur and chelonian eggshells. Jour. Vert. Pal., v. 18, no.2, pp. 348-362.

MOHABEY, D.M. (2000) Understanding community structure,nesting and extinction of Upper Cretaceous (Maastrichtian)Indian dinosaurs: evidences from eggs and nests. Gond. Geol.Mag., v. 15(2), pp. 1-23.

SAHNI , A. and GUPTA, V.J. (1982) Cretaceous egg shell fragmentsfrom the Lameta formation, Jabalpur, India. Bull. I. G. A.,v. 15, no.1, pp. 85-88.

SRIVASTAVA , A.K. and MANKAR , R.S. (2010) Sedimentologicalstudies and trace fossils of the Lameta successions of Bairam,Belkher and Salbardi area, district Amravati, Maharashtra andBetul, Madhya Pradesh. Gond. Geol. Mag., Spec. Vol., 12,pp. 209-224.

SRIVASTAVA , A.K. and MANKAR, R.S. (2012) Field characteristics,petrography and diagenesis of Lameta sediments exposed atnorthern boundary of district Amravati, Maharashtra.Gondwana Geol. Mag., v. 27, no. 1, pp. 31-42.

SRIVASTAVA , A.K. and MANKAR, R.S. (2013a) A dinosaurian ulna

from a new locality of Lameta Succession, Salbardi Area,districts Amravati, Maharashtra and Betul, Madhya Pradesh.Curr. Sci. v. 105, no. 7, pp. 900-901.

SRIVASTAVA , A.K. and MANKAR , R.S. (2013b) Lithofaciesarchitecture and depositional environment of Late CretaceousLameta Sediments, Central India. Arab. Jour. Geosci. DOI10.1007/s12517-013-1192-y.

SRIVASTAVA , A.K., BANUBAKODE, P.D., KALE, V.M., PATIL, G.V. andMANIK , S.R. (1999) Lower Cretaceous plant fossils fromBairam-Belkher area, district Amravati, Maharashtra anddistrict Betul, Madhya Pradesh and their significance instratigraphy. Palaeobotanist, v. 48, pp. 39-48.

SRIVASTAVA , A.K., MANIK , S.R. and GAWANDE, R.R. (2007) Diversityof gymnospermous plant remains from Upper Gondwana(Early Cretaceous) succession of Bairam-Belkher area, districtAmravati, Maharashtra and Betul, Madhya Pradesh. Phyto-morphology, v. 57, no. 3 & 4, pp. 153-163.

V IANEY-LIAUD, M., JAIN, S.K. and SAHNI, A. (1987) Dinosaur eggshells (Saurischia) from the Late Cretaceous Inter-trappeanand Lameta Formations (Deccan India). Jour. Vert. Pal., v. 7,pp. 408-424.

V IANEY-LIAUD, M., MALLAN , P., BUSCAIL, O. AND MONTGELARD. C.,(1994) Review of French dinosaur eggshells: morphology,structure, mineral, and organic composition. In: K. Carpenter,K. F. Hirsch, and J. R. Horner (eds.), Dinosaur Eggs andBabies, Cambridge University Press, Cambridge, pp. 151-183

ZHAO, Z., (1979) Discovery of the dinosaurian eggs and footprintsfrom Neixiang county, Hehan Province. Vert. Pal. Asiat.,v. 17, no.4, pp.304-309.

(Received: 29 July 2013; Revised form accepted: 23 January 2014)