Rich Vertebrate Research Articles

A MaxEnt predictive model for palaeontological sites in the Siwalik Hills: A case study from the Pinjor Formation of the Upper Siwalik Hills near Chandigarh, northern India

This study presents application of the MaxEnt predictive model to identify potential palaeontological sites in the Siwalik Hills, focusing on the Pinjor Formation near Chandigarh, northern India. The Siwalik region holds rich vertebrate palaeontological records, yet lacks comprehensive site prediction models. This research employs MaxEnt (3.4.0) software, to predict areas suitable for fossil occurrences. Georeferenced presence data was derived from literature and field surveys, for training the model. Environmental predictors including Pinjor geological deposit boundary, Vegetation Index (NDVI), and Slope and Aspect were from a digital elevation model. Furthermore, model development involved parameter tuning, for developing a potentially useful model. Field validation of the model through pedestrian surveys identified new fossil localities, demonstrating the model's practical applicability. This research emphasizes the importance of MaxEnt in developing site predictive models, offering a valuable tool for optimizing palaeontological field surveys. While highlighting the model's success, the study also recognizes its limitations, especially concerning landscape and vegetation changes over time. Overall, this work establishes a foundation for further research in predictive modelling for palaeontological exploration in the Siwalik region and emphasizes the need for multidisciplinary efforts in salvage palaeontology to mitigate anthropogenic threats.

Multiproxy approach to reconstruct the climate and environment of a new late Middle Pleistocene vertebrate site in northwestern Italy

The Moleto site (Ottiglio, AL, Piemonte, Italy) was discovered in the 1990s in an abandoned quarry carved into a Burdigalian–Langhian carbonate succession called Pietra da Cantoni. Sediment collection in three closely spaced fissures provided a rich vertebrate association whose age can be constrained to the late Middle Pleistocene on the basis of the presence of the extinct water vole Arvicola mosbachensis and its enamel characteristics (SDQ values ranging from 100 to 130). The very similar faunal content, evidenced by the common presence of Arvicola mosbachensis and its similar SDQ values, is indicative of a coeval deposition of the fillings of the three fissures. The vertebrate assemblage is represented by 30 taxa, including amphibians, squamate reptiles, birds, and mammals. Interestingly, a diverse fish assemblage from the embedded sediments of the Miocene Pietra da Cantoni has been found in the fissure fillings. We present here a multi-method approach using the small vertebrate assemblages (rodents, insectivores, amphibians, and squamate reptiles) from Moleto to characterize the environment and climate of the site. In order to reconstruct the palaeoenvironmental and palaeoclimatic conditions, we applied the Mutual Ecogeographic Range using UDA-ODA technique, the Bioclimatic Model, the Habitat Weightings, and the Quantified Ecology methods. The results revealed a landscape dominated by woodland habitats with presence of open humid meadows, under temperate and moist climatic conditions, although somewhat colder and drier than today. According to all evidence, the associations from Moleto would correspond to the interglacial MIS 7.

The first troodontid (Dinosauria: Theropoda) from the Upper Cretaceous Baruungoyot Formation of Mongolia

ABSTRACT Among non-avian dinosaurs, troodontids are relatively rare but diverse. The Nemegt Basin in the Mongolian Gobi Desert, which incorporates three of the most fossiliferous beds in the world, is one such region with high troodontid diversity and has also produced eight troodontid taxa until now. The diversity of troodontids is biased towards the two formations, Nemegt and Djadochta. Despite its rich vertebrate fossil record, no troodontids have been described from the Baruungoyot Formation. This faunal absence is perplexing as the Baruungoyot Formation has often been considered intermediate between the other two units in stratigraphy and paleoenvironment, but there are no definite troodontid materials that could fill this ‘gap.’ Here, we report a new troodontid, Harenadraco prima gen. et sp. nov., from the Baruungoyot Formation in Hermiin Tsav, Mongolia. It is represented by an incomplete skeleton that mainly consists of partially articulated left hind limb elements. Harenadraco is small and lightly built like other troodontids, but its tarsometatarsus exhibits extreme slenderness comparable only to Philovenator among cursorial non-avian maniraptorans. It also implies high cursoriality that could be an adaptation of Harenadraco to its environment where potential prey animals like mammals and predators such as eudromaeosaurs were likely to be agile. The discovery of Harenadraco confirms the presence of troodontids in all three formations in the Nemegt Basin. http://zoobank.org/urn:lsid:zoobank.org:pub:0981D708-986B-4B81-8809-E239DF9E8444

Dinosaur tracks with skin impressions in the La Buitrera Paleontological Area (Candeleros Formation, Cenomanian), Río Negro Province, Argentina

The La Buitrera Paleontological Area, in the north of the Río Negro Province, Argentina, preserves the uppermost section of the Cenomanian Candeleros Formation, as well as a rich vertebrate fauna that inhabited the Kokorkom Desert paleo-erg. Candia Halupczok et al. (2017) reported tracks found on wet and dry interdune. New evidence from 2020 to 2022 fieldtrips enabled the recognition of tracks in cross-section in non-channelized ephemeral fluvial dominated facies within the main aeolian setting located in the vicinity of the wettest recorded area of the La Buitrera Locality: the Cañadón de las Tortugas. The cross-section tracks commonly identified in these facies are from 30 to 75 cm long and 20–30 cm deep. Some of them preserve thin and shallow structures in the filling of the original track wall interpreted here as traces of the trackmaker integument. Specimens preserve two kinds of skin impressions. The first ones are parallel, mostly oblique striations, which sometimes cross each other at a high angle, produced by the pes during penetration and withdrawal from the substrate. The second ones are subrounded to polygonal, here interpreted as scale traces of the sole foot. Two clear, subtriangular to curved, and elongated, claw impressions are recorded in one track that allow us to relate it with a sauropod trackmaker.

Lepidosauromorphs and associated vertebrate fauna from the Late Triassic Tiki Formation, South Rewa, Gondwana basin, India: implication for paleoenvironment and paleobiogeography

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.

New data on the Miocene vertebrate assemblage of the Zaysan Basin (Central Asia) with implications for biostratigraphy, paleoecology, and paleobiogeography

ABSTRACT The Zaysan Basin in Central Asia has a long geological history, and it has therefore seen major climatic and evolutionary transformations. The Miocene fossil record of this locality is remarkably rich representing all groups of vertebrates. A revision of fish remains has been carried out and new records of fishes, reptiles, and mammals recovered from Miocene deposits of the Zaysan Basin have been described. The study of fossils has revealed the existence of a quite diverse vertebrate assemblage in the basin during the Miocene. Representatives of the Percidae and Amiinae, and the species †Leobergia zaissanica predominated among fishes, whereas reptiles were supposedly represented in the assemblage by pan-trionychid turtles and crocodiles. No amphibians have been revealed, while the only mammalian taxa in the studied sample is a fossorial rodent of the genus †Tachyoryctoides. In contrast to previous views regarding the Middle Miocene age of the Zaysan Formation, the analysis of fish and mammal remains recovered from this locality strongly suggests an Early Miocene age. Findings of bowfin remains in the Zaysan Basin confirm that this group had existed outside of North America beyond the Paleogene/Neogene transition, and, at the same time, these specimens are the last known occurrences of the taxa Amiidae, Amiiformes, and Halecomorphi outside of North America. Data also indicate the existence of a lacustrine ecosystem in the Zaysan Basin during the Miocene with a taxonomically rich vertebrate assemblage and diverse trophic relations being an important center of biodiversity in the Miocene of Central Asia.

The cave bears from Imanay Cave (Southern Urals, Russia)

ABSTRACT In the rich vertebrate fauna of Imanay Cave the abundant material of the small-sized cave bears was originally assigned to the taxon Ursus savini. Teeth and metapodials of statistical amounts were compared with other cave bear faunas and the taxonomic position was determined through morphological and metric analyses. The size of teeth and metapodial bones is significantly smaller in Imanay Cave bears compared to the typical U. deningeri from Mosbach and Hundsheim. Although the teeth are smaller, they reached higher evolutionary level than those from Mosbach or Hundsheim.The bear remains from Imanay Cave show great similarities to the fossils from Kizel Cave in the Ural Mountains described as Ursus rossicus Borissiak, 1930 but also to the remains of small-bodied cave bears of the Alps described as Ursus deningeroides Mottl, 1964. Remarkable are the differences in size of the front dentition: the incisors from Imanay Cave are on average >10% longer and wider than the corresponding teeth from U. deningeroides but also wider than the classic U. deningeri. Preliminary carbon and nitrogen stable isotope analyses suggest that the small cave bears from Imanay Cave were herbivorous.

First record of the microtoid rodent Microtocricetus Fahlbusch & Mayr 1975 from the South German karsts

ABSTRACT While the swabian and franconian karsts of southern Germany have yielded rich and important neogene vertebrate faunas, the middle to late Miocene transition is still extremely underrepresented. This period is however key for the understanding of the European mammal evolution. A microtoid rodent Microtocricetus M2 is described and commented in this paper. The fossil discovered in the karst filling Petersbuch 69 is regarded herein such as derived and might be thus the youngest fossil of the genus in Germany.

A comparative assessment on ant communities in three vegetation types located at Mfou Suburban locality of Yaoundé (Cameroon)

Urban expansion in Cameroon and many other Congo basin countries, involves the destruction of natural habitat previously colonized by a rich and diversified invertebrate and vertebrate fauna. In order to understand the dynamic of transformation of natural landscape into urban area on ant communities, a study was conducted at Mfou, a suburban agglomeration of Yaoundé. We aimed to evaluate the variation in ant diversity and ant community structure in relation to the type of habitat. Ants were collected on the ground and trees in cocoa farms, secondary forests, and palm groves using visual catch, pitfall traps, quadrat, and baits. We recorded 144 species belonging to 39 genera and 6 subfamilies. Cocoa farms (S= 102; H’= 3.83; E=0.83) were richer and more diversified than secondary forests (S= 100; H’= 3.83; E=0.83) and palm groves (S= 70; H’= 3.61; E=0.85). Myrmicinae, Formicinae and Ponerinae were the richest subfamilies both at genus and species levels. Based on their frequency of occurrence, Myrmicaria opaciventris (18.6%), Crematogaster striatula (17.1%), Crematogaster gabonensis (14.9%) and Camponotus crawleyi Emery, 1920 (14.2%) species were numerically dominant. Strumigenys sp.1, Strumigenys sp.2, Strumigenys sp.3, and Strumigenys sp.4 species were found only in secondary forests, suggesting the relatively stability of this habitat despite anthropogenic disturbance. Camponotus brevicollis, Technomyrmex sp.2 and Tetramorium guineensis were the indicator species in cocoa farms. In the secondary forests, Camponotus wellmani, Hypoponera punctatissima and Pheidole pulchella were found as indicator species while in palm groves H. punctatissima was the only indicator species.

The Early Pleistocene ectothermic vertebrates of Pietrafitta (Italy) and the last Western European occurrence of Latonia Meyer, 1843

The Early Pleistocene site of Pietrafitta (central Italy) produced a rich vertebrate assemblage from the Late Villafranchian Land Mammal Age (late MN18). Geological and paleobotanical data from Pietrafitta indicate a lacustrine environment, surrounded by a humid deciduous broadleaved forest with a temperate climate. The vertebrate assemblage consists of at least 40 taxa including actinopterygians, amphibians, reptiles, birds, and mammals. Here, we concentrate on the ichthyofaunal and herpetofaunal remains. The ichthyofauna includes Barbus Cuvier and Cloquet, 1816, Scardinius Bonaparte, 1837, aff. Squalius Cuvier, 1817, and Tinca Cuvier, 1817. The two anuran genera are the large-sized alytid frog Latonia Meyer, 1843 and the “green frog” Pelophylax Fitzinger, 1843. Three snake precloacal vertebrae were recognized, one attributed to Colubrines indet., another one to ­Natrix sp. Laurenti, 1768, and the largest and most complete vertebra is referred to the genus Vipera s.l. Laurenti, 1768 (cf. gr. “Oriental vipers”). The chelonian fossils, including some complete carapaces and plastrals, are attributed to the European pond turtle (Emys gr. Orbicularis Linnaeus, 1758) and Hermann’s tortoise (Testudo hermanni Gmelin, 1789).

A reassessment of the Oligocene hyracoid mammals from Malembo, Cabinda, Angola

The Oligocene Malembo locality, Cabinda exclave, Angola, has yielded a rich vertebrate fauna represented by fragmentary remains. This fossiliferous locality is the only definite occurrence of Oligocene terrestrial mammals in sub-Saharan West Africa. The hyracoids from Malembo have only been very succinctly described and compared thus far, so that their systematic attribution is not consensual among specialists. A revision now allows the identification of three (or four) medium to large-sized species represented by Geniohyus dartevellei, Pachyhyrax cf. crassidentatus, and two undetermined taxa. The species G. dartevellei is revived for the holotype of Palaeochoerus dartevellei Hooijer, 1963; this species is unique to Malembo but appears close to Geniohyus mirus, a species only known from the early Oligocene of the Fayum, Egypt. Other species of Geniohyus and Pachyhyrax crassidentatus are also only known from the early Oligocene of the Fayum. The presence of Geniohyus and Pachyhyrax cf. crassidentatus at Malembo thus supports an early Oligocene age for the fauna.

Additional vertebral material of Thaumastophis (Serpentes: Caenophidia) from the early Eocene of India provides new insights on the early diversification of colubroidean snakes

The Ypresian Cambay Shale Formation at Vastan, Mangrol, and Tadkeshwar lignite mines in Gujarat, western India, has yielded a rich vertebrate fauna including madtsoiid, palaeophiid, booid, and colubroidean-like snakes. The latter are particularly abundant, but their systematic affinities are difficult to resolve. Here we describe new specimens of the colubroidean-like snake Thaumastophis missiaeni, including anterior, middle, and posterior trunk vertebrae, as well as caudal vertebrae. The combination of primitive and derived caenophidian and colubroidean vertebral characters confirms Thaumastophis as the earliest known stem-colubriform snake while Procerophis, from the same beds, is more derived and considered to represent a crown-Colubriformes. Additionally, Thaumastophis shares with Renenutet enmerwer from the late Eocene of Egypt a unique combination of vertebral characters that suggests an exchange with North Africa was possible along the southern margin of the Neotethys. We erect the new family Thaumastophiidae for Thaumastophis and Renenutet on the basis of their shared derived vertebral morphology.

First evidence of an ankylosaur (Dinosauria, Ornithischia) from the Jurassic Qigu Formation (Junggar Basin, NW China) and the early fossil record of Ankylosauria

The first evidence of an ankylosaur from the Late Jurassic Qigu Formation of the southern Junggar Basin (Xinjiang, northwestern China) is described, based on an isolated caudal vertebra that was discovered together with fragmentary remains of other dinosaurs, including stegosaurs, sauropods, and theropods. The caudal vertebra is characterized by the following features: (i) elliptical morphology of the centrum, being wider than high; (ii) short antero-posterior length of the centrum; (iii) pronounced transversely extending ventral groove; (iv) massive transverse process, that is longer than the centrum diameter; (v) transverse process meeting the centrum high at the dorsal half and at a relatively flat angle; (vi) transverse process making a broad contact with the neural arch without forming a proximo-dorsal projection; and (vii) notochordal prominence present in the centre of the anterior articular surface. The study specimen represents only the second record of an ankylosaur from the Jurassic of Asia — aside from the slightly older Tianchisaurus from the early Upper Jurassic Toutunhe Formation, equally from the Junggar Basin. It helps to fill a gap in our knowledge of the early evolution of these armoured dinosaurs. Additionally, this discovery highlights the potential of the southern Junggar Basin to yield a rich vertebrate fauna and thus to provide an important insight into Late Jurassic ecosystems of Central Asia.

The Late Middle Miocene Mae Moh Basin of Northern Thailand: The Richest Neogene Assemblage of Carnivora from Southeast Asia and a Paleobiogeographic Analysis of Miocene Asian Carnivorans

The late middle Miocene fossil-bearing lignite zones of the Mae Moh Basin, northern Thailand, have yielded a rich vertebrate fauna, including two species of Carnivora described thus far: the bunodont otter Siamogale thailandica (known from over a 100 specimens) and the large amphicyonid Maemohcyon potisati. Here we describe additional carnivoran material from Mae Moh comprising new remains of Maemohcyon potisati as well as remains of seven new carnivorans belonging to at least four families: a new species of Siamogale (S. bounosa), a new species of another otter (Vishnuonyx maemohensis), one representative of the genus Pseudarctos (a small amphicyonid), a new genus of Asian palm civet, Siamictis, one representative of another civet (cf. Viverra sp.), a new species of mongoose (Leptoplesictis peignei) and a Feliformia indet. This carnivoran assemblage constitutes one of the richest for the middle Miocene of eastern Asia and by far the richest for the Neogene of Southeast Asia.While the presence of new species indicates a certain degree of endemism for the Mae Moh Basin, paleobiogeographic cluster analyses conducted on carnivoran faunas from the middle and late Miocene of Asia indicates that a southern Asian biogeographic province, analogous to the current Oriental Realm, has existed since at least the middle Miocene. These results strengthen the observation that the Himalayan Mountains and Tibetan Plateau constitute significant physical barriers as well as an important climatic barrier (through the strengthening of monsoon systems) preventing north-south mammal dispersals in Asia since at least the middle Miocene.

Testing the hypothesis of an impoverished predator guild in the Early Miocene ecosystems of Patagonia: An analysis of meat availability and competition intensity among carnivores

The lower Miocene Santa Cruz Formation (dated to ~18–16 Ma) of Southern Patagonia, Argentina, preserves rich vertebrate faunas, which are representative of communities that existed prior to the Great American Biotic Interchange (GABI). Some previous researchers have hypothesized that these pre-GABI faunas had a low richness of mammalian carnivores (an impoverished predator guild), while others argue for a predator/prey ratio similar to those of recent communities. In this paper, we analyze faunas from the lower part of the Santa Cruz Formation (FL 1–7) using a methodology that allows us to quantify (i) the meat resources that were available to the secondary consumers of the palaeocommunity; and (ii) the competition intensity for these resources. In our modeling, we considered different scenarios related to meat consumption, including the possibility that several taxa had a scavenging behavior, and also differences in mortality rates between young and adult prey. Our results provide estimates of the nutritional requirements from the predator/scavenger guild under maximum and minimum quantities of meat offered by the prey community, which indicate the presence of a well-balanced palaeocommunity. Moreover, the competition indices point to a relatively high level of competition for prey of small-to-medium size, although competition for resources from large mammal prey was rather low. This suggests that the predator/scavenger guild was not impoverished, although there were insufficient carnivore species to fully consume the megaherbivore biomass.

Fossil horses from the Late Pleistocene of Tapalqué Creek (Buenos Aires Province, Argentina)

A comparative study was made with the known record of equids species in South America, identifying the remains as Equus neogeus, Hippidion devillei, and Hippidion principale. These data increase the record of Equidae in South America and provide new evidence about the chronological and geographical distribution. The sedimentary deposits of the Lujan Formation outcropping at Tapalqué creek (4 to 120 ky) were accumulated through fluvial processes. This Formation comprises a rich vertebrate fauna corresponding to the Lujanian South American Land Mammal Age, which includes numerous and diverse vertebrate remains. The taphonomic analysis indicates that the faunistic assemblage was formed and was subject to diagenetic processes without distinction of its action in the fossiliferous levels, that can be recognized as fluvial deposits.

First discovery of avian egg and bone remains (Presbyornithidae) from the Gour Lazib (Eocene, Algeria)

Numerous avian eggshells and one well-preserved small ovoid-shaped egg (32 × 28 mm) were collected from three localities in the Gour Lazib area (HGL10, HGL51 and HGL62), western Algeria from the Glib Zegdou Formation dated from the late early or early middle Eocene. This material was associated with a rich vertebrate fauna. The study of the eggshells using microscopies (PLM and SEM) led to attribute them to neognathous birds. They are characterized by a thin shell (less than 0.5 mm thick) with a prismatic trilaminate microstructure. The occurrence of an avian carpometacarpus belonging to the Presbyornithidae from HGL50, which is located 1 m below the HGL 51 level, suggests that the egg remains may be referred to this bird family, which is so far unknown in the Palaeogene of the Afro-Arabian continent.

A contribution to the herpetofauna from the late Miocene of Gritsev (Ukraine)

Excavations in the locality Gritsev (karstic fillings of the upper Miocene age in a limestone quarry in Shepetovsky District, Khmelnitsky Region, Ukraine) revealed, since 1983 when excavations started, a rich vertebrate fauna that includes also amphibians and lizards. The material is rich enough to assess individual and developmental variation within some taxa (e.g., Pseudopus pannonicus). Although the fragmentary nature of the disarticulated bones does not sometimes allow precise taxonomic assignment, morphological differences in, e.g., dental characteristics suggest the presence of some other ones, not formally named forms. Thus, the list of the amphibian and reptilian taxa from Gritsev is by far not complete, but their osteological characteristics are representative to such a degree that they can provide information for comparisons with other European Miocene herpetofaunas.

The Palaeotheriidae (Equoidea, Perissodactyla, Mammalia) from the Eocene fauna of Aumelas (Hérault department, France)

The rich vertebrate fauna of Aumelas has from decades been the subject of several partial publications, which led to assign it an age close to the MP 13 reference level in the biochronological scale of Western European mammals; but it is still partially unpublished and this paper is part of a general review of the fauna. With regard to equoid perissodactyls, five taxa have been distinguished, to be assigned to the “Pachynolophinae” to the exclusion of any Palaeotheriinae. Two leading species appear in this ensemble: Propalaeotherium sudreiRemy, Krasovec & Marandat, 2016 and Pachynolophus ruscassierensis n. sp. The three other taxa are less documented, which prevents a specific determination, Pachynolophus sp., Propalaeotherium cf. gaudryi (Lemoine, 1878) and Lophiotherium sp. All of these species display relatively archaic features as highlighted by a cladistic analysis. Such a conclusion challenges the hitherto prevailing consensus on the dating of the fauna, in the sense of an older biochronological age. This discrepancy will be discussed in a subsequent synthetic work, in conjunction with specialists of all mammal and reptile orders represented in the locality.

A large crocodyloid from the Oligocene of the Bugti Hills, Pakistan

Cenozoic continental deposits of the Bugti Hills crop out south of the Sulaiman Range in Balochistan, Pakistan. These have been renowned since Vickary (1846) for their exceptionally rich vertebrate...