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New dinosaur species from the Upper Triassic Upper Maleri and Lower Dharmaram formations of Central India
Abstract and Figures
The beginning of dinosaur evolution is currently known based on a handful of highly informative Gondwanan outcrops of Ischigualastian age (late Carnian–early Norian). The richest Triassic dinosaur records of the southern continents are those of South America and South Africa, with taxonomically diverse faunas, whereas faunas from India and central Africa are more poorly known. Here, the known diversity of Gondwanan Triassic dinosaurs is increased with new specimens from central India, which allow a more comprehensive characterisation of these dinosaur assemblages. Five dinosauriform specimens are reported from the probable late Norian–earliest Rhaetian Upper Maleri Formation, including two new sauropodomorph species, the non-plateosaurian Nambalia roychowdhurii and the plateosaurian Jaklapallisaurus asymmetrica, a guaibasaurid and two basal dinosauriforms. The Lower Dharmaram Formation, probably latest Norian–Rhaetian in age, includes basal sauropodomorph and neotheropod remains, providing the second record of a Triassic Gondwanan neotheropod. The currently available evidence suggests that the oldest known Gondwanan dinosaur assemblages (Ischigualastian) were not homogeneous, but more diverse in South America than in India. In addition, the Upper Maleri and Lower Dharmaram dinosaur assemblages resemble purported coeval South American and European beds in the presence of basal sauropodomorphs. Accordingly, the current available evidence of the Triassic beds of the Pranhita–Godavari Basin suggests that dinosaurs increased in diversity and abundance during the late Norian to Rhaetian in this region of Gondwana.
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... Aetosaurian remains have been reported from the Maleri and Dharmaram formations (Kutty & Sengupta, 1989;Kutty et al., 1987Kutty et al., , 2007Novas et al., 2011;von Huene, 1940). The Dharmaram osteoderms were subsequently identified as belonging to Paratypothorax-like and Desmatosuchus-like taxa (Bandyopadhyay, 2011;Bandyopadhyay & Ray, 2020;Desojo et al., 2013;Kutty & Sengupta, 1989), though these lack proper documentation and detailed description. ...
... The formation has yielded two distinct vertebrate faunal assemblages and encompasses the Triassic-Jurassic boundary (Bandyopadhyay & Roy-Chowdhury, 1996). Various vertebrate fossils have been recovered from the lower Dharmaram Formation that included a ptychoceratodontid (Bandyopadhyay & Ray, 2020;Kutty & Sengupta, 1989), a xenacanthid (Nath & Yadagiri, 2007;Prasad et al., 2008), a Nicrosaurus-like phytosaur, Paratypothorax-like and Desmatosuchus-like aetosaurs, several sauropodomorphs, and a neotheropod (Bandyopadhyay, 2011;Bandyopadhyay & RoyChowdhury, 1996;Bandyopadhyay & Ray, 2020;Kutty et al., 2007;Novas et al., 2011). Based on an essentially archosaur-dominated fauna, the age of the lower Dharmaram Formation is considered to be latest Norian to Rhaetian (Bandyopadhyay & Sengupta, 2006;Bandyopadhyay & Ray, 2020). ...
... Locality, Horizon, and Age-Near the village of Rampur (19° 9′54″N, 79°35′6″E; Fig. 1D), Adilabad district, Telangana, India; lower Dharmaram Formation of the Pranhita-Godavari Basin; Upper Triassic: middle Norian to Rhaetian (Bandyopadhyay & Sengupta, 2006;Bandyopadhyay & Ray, 2020;Kutty et al., 2007;Novas et al., 2011;current study). ...
A new typothoracine aetosaur is described based on multiple isolated and articulated left paramedian and lateral osteoderms recovered from the Upper Triassic lower Dharmaram Formation of India. The partial carapace of the new taxon is reconstructed as strongly discoidal based on the curvature of the paramedian osteoderms with the widest one positioned dorsal to the mid-dorsal trunk vertebra. Asymmetric lateral osteoderms with acute flexion are considered as precaudals with the angle of flexion decreasing posteriorly. Phylogenetic analysis recovered the new taxon as deeply nested within the clades Typothoracinae and Paratypothoracini, and a sister taxon to Kocurypelta silvestris. The autapomorphic characters involving paramedian osteoderms dorsal to the trunk vertebrae include dorsal surface ornamented by large, irregular pits surrounding the dorsal eminence and radiating ridges in other areas, straight anterior margin of the anteromedial corner of the anterior bar in dorsal view, and raised or ridged and ornamented posteromedial corner. The current study highlights the significance of the new aetosaur, and the age of the lower Dharamaram Formation is modified here as mid-Norian to Rhaetian based on global correlation with other coeval horizons. The recovery of this taxon marks the first record of Paratypothoracini from high paleolatitudes of the Gondwanan region. The study corroborates the earlier findings of a strong Laurasian faunal influx in India during the Late Triassic suggesting possible land bridges and/or conducive environmental conditions for faunal dispersal. http://zoobank.org/urn:lsid:zoobank.org:pub:FCC37C0E-107F-4B15-9460-4E802B465865
... The last eight decades have seen a very productive period for the history of dinosaur research in India, and numerous dinosaur clades of Triassic and Jurassic ages have been identified in the Maleri, Dharmaram and Kota formations of the Pranhita-Godavari valley (e.g. Huene 1940;Colbert 1958;Jain et al. 1964Jain et al. , 1975Jain et al. , 1979Roy-Chowdhury 1965;Kutty 1969;Chatterjee 1967Chatterjee , 1974Chatterjee , 1978Chatterjee , 1980Chatterjee , 1982Chatterjee , 1987Chatterjee and Roy-Chowdhury 1974;Yadagiri 1982;Jain and Roy-Chowdhury 1987;Yadagiri and Rao 1987;Yadagiri et al. 1979;Yadagiri 1988Yadagiri , 2001Kutty et al. 1987Kutty et al. , 2007Kutty and Sengupta 1989;Chatterjee and Creisler 1994;Bandyopadhyay and Roy-Chowdhury 1996;Loyal et al. 1996;Bandyopadhyay 1999;Nath et al. 2002;Bandyopadhyay and Sengupta 2006;Spielmann et al. 2006;Bandyopadhyay et al. 2002Bandyopadhyay et al. , 2010Novas et al. 2010Novas et al. , 2011Kammerer et al. 2016;Chatterjee et al. 2017; Galton 2019; Chatterjee 2020; Bandyopadhyay and Ray 2020; Prasad and Parmar 2020; Khosla and Bajpai 2021). Middle Jurassic dinosaurs have also been discovered in western peninsular India (Figure 1). ...
... 1987; Chatterjee and Creisler 1994). Five dinosauriform/dinosaur taxa have been reported from the Upper Maleri Formation, Nambalia roychowdhurii (a basal sauropodomorph), Jaklapallisaurus asymmetrica (a plateosaurian), an unnamed member of Guibasauridae and two Dinosauriformes indet (Table 3, Kutty 1969;Novas et al. 2011). ...
... Parts of the front ends of the upper and lower jaws, many fragmentary and incomplete vertebrae (Figures 3 and 4) from all parts of the spinal column, the majority of a femur, and an astragalus (ankle bone) make up the only known specimen of Alwalkeria maleriensis (holotype ISI R306, Chatterjee 1987;Chatterjee and Creisler 1994). According to recent studies by Novas et al. (2011), Alwalkeria is a legitimate and valid species due to autapomorphies that include its unique femur and astragalus morphology. ...
We review the record of Late Triassic and Jurassic dinosaurs from India to determine their geological ages
and palaeobiogeographic significance. The oldest Indian dinosaur, the basal saurischian Alwalkeria maleriensis,
is from the early Late Triassic (Otischalkian/Carnian) lower Maleri Formation. The archosaur-dominated
Upper Maleri Formation (Adamanian/late Carnian?) contains two sauropodomorph clades. The Indian
Jurassic record of dinosaurs from the Pranhita-Godavari Valley is more extensive but has poor age constraints,
whereas fragmentary, and better dated dinosaur remains are known from the Early Middle Jurassic
of Kachchh, Gujarat and Rajasthan. The Indian Late Triassic dinosaurs fit into a picture of some degree of
dinosaur cosmopolitanism across Late Triassic Pangaea, with primitive saurischians and/or theropods and
primitive sauropodomorphs found in eastern Gondwana (India), western Gondwana (South America) and
Euramerica. The well-known non-neosauropods Kotasaurus and Barapasaurus from the Middle Jurassic Kota
Formation provide substantial evidence that India was a major centre of the early evolution of neosauropods.
Tharosaurus indicus, from the Middle Jurassic strata of the Jaisalmer Basin, is a relic of a lineage that
likely originated in India and swiftly expanded throughout the rest of Pangaea. This lineage further stresses
the significance of Gondwanan India in elucidating the origin and early evolutionary history of neosauropod
dinosaurs.
... Modified from Kutty and Sengupta (1989). Upper Maleri Formation, Pranhita-Godavari Valley, of central India (Kutty & Sengupta, 1989;Novas et al., 2010;Figure 1a,b). The first dinosaur discoveries in this unit were reported by Kutty et al. (1987) and Kutty and Sengupta (1989) and were subsequently identified as small, early-diverging sauropodomorphs (Massospondylus sp. in Kutty et al., 1987;aff. ...
... Guaibasaurus in Kutty et al., 2007). It was not until more recently that these dinosaur specimens were described, including an unnamed herrerasaurian and an early sauropodomorph, and two nominal species that were erected at that time, the nonsauropododiform sauropodomorphs Nambalia roychowdhurii and Jaklapallisaurus asymmetrica (Novas et al., 2010;Figure 1d). All these dinosaur taxa were described briefly and with a limited number of illustrations as part of a broader paper documenting the dinosaur assemblages of the Upper Maleri and, its overlying unit, the Lower Dharmaram formations. ...
... which are available as Supplementary Information Salgado et al. (1997) Plateosauria Tornier, 1913sensu Yates (2007. Unaysauridae Müller, Langer & Dias-da-Silva, 2018 Jaklapallisaurus asymmetricus Novas, Ezcurra, Chatterjee & Kutty, 2010 Comment The ending of the latinized specific epithet was changed from the female "asymmetrica" to the masculine "asymmetricus" because the ending of the latinized genus Jaklapallisaurus is masculine. This modification is based on the Article 34 of the International Code of Zoological Nomenclature and following this article the author and date of the species remain unchanged. ...
The Gondwana formations exposed in the Pranhita‐Godavari Valley of central India include Middle Triassic to Lower Jurassic continental deposits that provide essential information about the tetrapod assemblages of that time, documenting some of the oldest known dinosaurs and the first faunas numerically dominated by this group. The Upper Maleri Formation of the Pranhita‐Godavari Basin preserves an early‐middle Norian dinosaur assemblage that provides information about the early evolutionary history of this group in central‐south Gondwana. This assemblage comprises sauropodomorph dinosaurs and an herrerasaurian, including two nominal species. Here, we describe in detail the anatomy of one of those early dinosaurs, the bagualosaurian sauropodomorph Jaklapallisaurus asymmetricus . The new anatomical information is used to investigate the position of the species in an updated quantitative phylogenetic analysis focused on early sauropodomorphs. The analysis recovered Jaklapallisaurus asymmetricus as a member of Unaysauridae, at the base of Plateosauria, together with Macrocollum itaquii and Unaysaurus tolentinoi from the early Norian of southern Brazil. This phylogenetic result indicates that the dispersal of early plateosaurian sauropodomorphs between the Southern Hemisphere and what nowadays is Europe would have occurred shortly after Ischigualastian times because of the extension of their ghost lineage. Thus, the presence of early plateosaurians in the early Norian of South America and India reduces a previously inferred diachrony between the biogeographic dispersals of theropods and sauropodomorphs during post‐Ischigualastian times.
... Whatever their starting point, dinosaurs were certainly widespread by the mid-Norian (ca 220−215 Ma), maintaining their presence in Gondwana and supposedly occurring for the first time in North America and Europe [1,[3][4][5]7,15,[40][41][42]. Closer inspection reveals a more nuanced picture, with herrerasaurians and theropods being the most widespread Norian dinosaurs and apparently reaching the northern hemisphere earlier, either in the mid-Norian (ca 219 Ma) [9] or in late Carnian [39]. ...
... Although climate may have facilitated increased Laurasian cosmopolitanism in the Early Jurassic, Button et al. [76] linked the latter to recovery from the end-Triassic mass extinction (ETE). Theropods and ornithischians may have diversified soon after the ETE, potentially taking advantage of niches left vacant by various non-dinosaurian groups such as phytosaurs and ornithischians [3][4][5]7,18,31,41,43,44,[77][78][79][80][81][82], though see [45,63] for climate-based interpretations. Several important new lineages were present by the Early Jurassic, including tetanuran and ceratosaurian theropods [83] and the armoured thyreophoran ornithischians [84][85][86]. ...
Dinosaurs potentially originated in the mid-palaeolatitudes of Gondwana 245–235 million years ago (Ma) and may have been restricted to cooler, humid areas by low-latitude arid zones until climatic amelioration made northern dispersals feasible ca 215 Ma. However, this scenario is challenged by new Carnian Laurasian fossils and evidence that even the earliest dinosaurs had adaptations for arid conditions. After becoming globally distributed in the Early–Middle Jurassic (200–160 Ma), dinosaurs experienced vicariance driven by Pangaean fragmentation. Regional extinctions and trans-oceanic dispersals also played a role, and the formation of ephemeral land connections meant that older vicariance patterns were repeatedly overprinted by younger ones, creating a reticulate biogeographic history. Palaeoclimates shaped dispersal barriers and corridors, including filters that had differential effects on different types of dinosaurs. Dinosaurian biogeographic research faces many challenges, not the least of which is the patchiness of the fossil record. However, new fossils, extensive databasing and improved analytical methods help distinguish signal from noise and generate fresh perspectives. In the future, developing techniques for quantifying and ameliorating sampling biases and modelling the dispersal capacities of dinosaurs are likely to be two of the key components in our modern research programme.
... The ratio between the maximum anteroposterior length of the proximal end of the tibia and overall tibia length varies among Late Triassic sauropodomorph taxa, from the most slender in Jaklapallisaurus asymmetricus Novas et al., 2011(0.24, Ezcurra et al. 2023 Otero and Pol 2013, PVL 3808, respectively), Plateo sauravus cullingworthi (0. 40, Haughton 1924), and Melanorosaurus readi Haughton, 1924 (0.43, SAM-PK-3449;Haughton 1924), to the stockiest in Bli kana saurus cromptoni Van Heerden, 1985 (0.48, Galton andVan Heerden 1985). ...
... The Zimbabwean sauropodomorph assemblage is therefore similar to the mixture of sauropodomorph taxa known from the Elliot Formation of the MKB (McPhee et al. 2017), which yields species-rich faunas comprising early diverging massopodans and sauropodiforms (although very early diverging sauropodomorph taxa are currently unknown from the MKB). Similar mixtures of non-massopodans and massopodans also occur in the Late Triassic basins of South America (Pol et al. 2021) and India (Novas et al. 2011). ...
The central region of Rio Grande do Sul State, in southern Brazil, has increasing importance due the discoveries of Triassic fossils, including some of the world’s oldest dinosaurs and their tracks. Tridactyl footprints of Carnian age, from the Santa Maria Formation, have been identified as ?Grallator isp., in addition to indeterminate tracks of dinosaurs. These footprints are attributed to basal dinosauriforms and they are considered the earliest examples of dinosaur tracks in Brazil. These discoveries hold significant implications, as they are associated with a diverse fauna whose dating aligns with the Carnian Pluvial Episode. This is a pivotal period marked by substantial environmental changes linked to global warming, leading to significant extinctions and transitions in both flora and fauna. Other tracks, dating back to the Norian or possibly Rhaetian age, were reinterpreted as “Theropod tracks indet.”, and were produced by large theropod dinosaurs. These particular occurrences are connected to the Caturrita Formation and provide valuable insights into a later episode following the climate changes and their resulting effects on faunal and floral composition. Previously registered tracks within the Caturrita Formation at the Novo Treviso site, attributed to prosauropod dinosaurs, have been reinterpreted as belonging to the Guará Formation, ranging from the Late Jurassic to the Early Cretaceous. Thus, the Santa Maria-Caturrita sequence, a sedimentary record shaped by diverse processes in ancient fluvial systems, offers an almost continuous timeline of the transition between the emergence of dinosaurs and their eventual establishment as ecologically dominant elements in continental faunas. These Brazilian Triassic dinosaur tracks, albeit limited to two strata at present, provide valuable supplementary data to the osteological record, further reinforcing these significant events in paleontological history.
Just after the end-Permian Mass Extinction Event, the onset of Triassic period records an impoverished terrestrial vertebrate diversity end-Permian extinction event that is succeeded by the advent of new and diverse faunas that peaked during the Late Triassic. Such variations in vertebrate diversity is also reflected in the fossil record of the Gondwana basins of India. In a span of four years (2020–2024), multiple work from India has considerably enhanced this Triassic vertebrate record by addition of various new tetrapods. This included a proterosuchian from the Early Triassic, a large, herbivorous and horned azendohsaurid and an erythrosuchid from the Middle Triassic, and various phytosaurs, aetosaurs, a dome-headed archosauromorph and a small carnivorous azendohsaurid from the Late Triassic. These studies highlighted the biostratigraphic and biogeographic significance of the fossil finds and helped in the better understanding of the Triassic scenario of India.
Many recent studies of theropod relationships have been focused on the phylogeny of coelurosaurs and the question of the origin of birds, but the interrelationships and evolution of basal theropods are still poorly understood. Thus, this paper presents a phylogenetic analysis of all theropods, but focuses on the basal members of this clade. The result supports the inclusion of Eoraptor and herrerasaurids in the Theropoda, but differs from other recent studies in two main aspects: (1) The taxa usually grouped as ceratosaurs form two monophyletic clades that represent successively closer outgroups to tetanurans. The more basal of these clades, the Coelophysoidea, comprise the majority of Late Triassic and Early Jurassic theropods. The other clade of basal theropods that are usually included in the Ceratosauria comprises Ceratosaurus, Elaphrosaurus, and abelisaurids. (2) Two monophyletic groups of basal tetanurans are recognized: the Spinosauroidea and the Allosauroidea. In contrast to other recent phylogenetic hypotheses, both clades are united in a monophyletic Carnosauria. The branching pattern of the present cladogram is in general accordance with the stratigraphic occurrence of theropod taxa. Despite the differences in recent analyses, there is a significant level of consensus in theropod phylogeny. At least four different radiations of non-avian theropods can be recognized. These radiations show different patterns in Laurasia and Gondwana, and there are increasing differences between the theropod faunas of the two hemispheres from the Triassic to the Cretaceous.
FIGURE 9. Photographs of dorsal vertebrae 9 – 11 in right lateral view (a) and the centrum of the 12 th dorsal vertebra (b) in cranial view. Abbreviations: d 9 – d 11, dorsal vertebrae 9 to 11. Scale bar = 2.5 cm.
The Gondwana Sequence in the northern part of the Pranhita-Godavari Valley consists of four formations of the Lower Gondwana and seven formations of the Upper Gondwana. The gross lithological characters and mappability are considered as the major criteria for delineating the formations. The name Kamthi Formation which has been used by different authors in different senses, is here used in the sense of Sengupta (1970). The rocks between the Barakar and this Kamthi are divided into four lithozones for limitations of mappability. Although some of these lithozones have earlier been designated as formations, at present not sufficient information is available to justify this. Only two breaks, both within the Upper Gondwana, are found to be present: there is no recognisable break between the Lower and the Upper Gondwana. A summary of this succession is presented in tabular form taking into account the words of earlier authors. The alternative views that are radically different from the one presented here are also discussed briefly. The usefulness of plant megafossils and fossil vertebrates in understanding the stratigraphy is discussed briefly and their role in determining the possible geological ages of some of the formations is mentioned. The vertebrate fauna from a number of formations is listed. At least seven formations are fossiliferous as far as vertebrates are concerned. Of these, two belonging to the Triassic and one belonging to the Jurassic are quite well-documented. The other four are less well known, but serve as very useful time markers. All these vertebrate-bearing formations can be correlated with co-eval rocks elsewhere in the world. The difficulty of correlating continental deposits is realized and keeping this in view a tentative correlation is presented.
The Gangapur beds, believed to be the basal beds of the Upper Gondwana Kota formulation, are here shown to overlie the latter unconformably. This discovery, based on detailed mapping, clears up a long standing confusion, i.e. of a flora from the Gangapur beds judged to be later in age than the Kota fauna, but successionally preceding it. The Gangapur beds are hence removed from the Kota formation and are called here the Gangapur formation.
The base of the Kota formation is redefined on the basis of faunal and lithological evidence. A new, late Upper Triassic, fauna has been discovered below the Kota beds, which is quite different from the typical, early Upper Triassic, Maleri fauna and also from the Lower Jurassic Kota fauna. On this faunal basis as well as on stratigraphic grounds the erection of a new formation (here called the Dharmaram formation) is suggested, and the boundary of the Maleri and Dharmaram formations is defined.