Paleobiota from the Deccan volcano-sedimentary sequences of India: paleoenvironments,age and paleobiogeographic implications

Paleobiotic assemblages from the Deccan infra- and intertrappean beds are reviewed in great detail. Three distinct paleoenvironments (fluvio-lacustrine/terrestrial, brackish water and marine) have been identified within the infra- and intertrappean biotic assemblages of peninsular India. Recently, marine incursions have been recorded in a few of the Deccan intertrappean beds exposed in central and south-eastern India. The intertrappean beds have yielded marine planktic foraminiferans and freshwater/brackish water ostracods. The affinities of the paleobiotas are commonly considered to show a mixed pattern resulting from the addition of Gondwanan and Laurasian elements to endemic Indian taxa. During the last four decades, various biogeographic models (southern and northern connections) have been proposed to explain the presence of anomalous biogeographic biota in the Late Cretaceous of India. Based on the recovered fauna and flora assemblages, the Cretaceous–Paleogene boundary has been marked and a Late Cretaceous to Early Paleocene age has been assigned to these Deccan volcano-sedimentary sequences.     

Coryphoid palms from the K-Pg boundary of central India and their biogeographical implications: Evidence from megafossil remains

Ten palm leaf impressions are documented from the latest Maastrichtian (late Cretaceous) to early Danian (earliest Paleocene) sediments (K-Pg, c. 66–64 Ma) of the Mandla Lobe of the Deccan Inter-trappean Beds, Madhya Pradesh, central India. The palmate leaf shape along with a definite well-preserved costa support their placement in the subfamily Coryphoideae of the family Arecaceae. We place all recovered palm leaf specimens in the fossil genus Sabalites, report seven species of coryphoid palms and describe two new species namely, Sabalities umariaensis sp. nov. and Sabalites ghughuaensis sp. nov. The fossils indicate that coryphoid palms were highly diverse in central India by the latest Cretaceous. These and earlier reported coryphoid palm fossils from the same locality indicate that they experienced a warm and humid tropical environment during the time of deposition. These discoveries confirm the presence of a diversity of Coryphoideae in Gondwana prior to the India-Eurasia collision and provide information about coryphoid biogeographical history over geological time. Based on megafossil remains, we trace coryphoid palm migration pathways from India to mainland Southeast (SE) Asia and other parts of Asia after the docking of the Indian subcontinent with Eurasia early in the Paleogene.     

First fossil evidence of Palaeocarya (Engelhardioideae: Juglandaceae) from India and its biogeographical implications

Even though presently indigenous to eastern Himalaya in India, no Engelhardioideae have been reported from the Cenozoic sediments of India till date. Here, we report the first Indian occurrence of a characteristic engelhardioid winged samaroid fruit having a tri-lobed wing (oblong-ovate median lobe and two lateral lobes) and a globose nut from the latest Neogene (Pliocene: Rajdanda Formation) sediments of Chotanagpur Plateau, eastern India. This is the first fossil evidence of relict family Juglandaceae from the Indian Cenozoic. We determine its taxonomic position on the basis of detailed macromorphological comparison with similar extant and fossil specimens and discuss its palaeoclimatic significance in terms of the present-day distribution of modern analogous species. We assign this Pliocene winged fruit specimen to the morphogenus Palaeocarya sect. Monocosta Manchester and describe it as a new species, namely Palaeocarya indica Hazra, Hazra M & Khan sp. nov. Palaeocarya sect. Monocosta has rich fossil records from the Cenozoic sediments of Europe, North America, and eastern Asia (China, Korea), but the modern analog, Engelhardia, is presently native only to India and neighboring Southeast Asia. We discuss the possible causes of disappearance of Engelhardia from the present-day vegetation of Chotanagpur Plateau. Its disappearance may be related to the gradual intensification of monsoonal rainfall seasonality since the Pliocene. Here, we also review in detail the biogeographic history of Palaeocarya sect. Monocosta and suggest its possible migration routes.     

A new Hyperodapedon (Archosauromorpha,Rhynchosauria) from the Upper Triassic of India: implications for rhynchosaur phylogeny

A new species of the rhynchosaur genus Hyperodapedon, namely H. tikiensis, is described from well‐preserved skeletal elements that were collected from the Upper Triassic Tiki Formation of India. Hyperodapedon tikiensis is diagnosed on the basis of several cranial and postcranial features including longer than wide basipterygoid process, crest‐shaped maxillary cross section lateral to the main longitudinal groove, deeply excavated neural arches of mid‐dorsal vertebrae, long scapular blade, a pronounced deltopectoral crest, proximal humeral end much broader than distal end, iliac length greater than iliac height, equal pre‐ and postacetabular iliac lengths and circular femoral cross section. Two distinct morphotypes of the maxillary tooth plates can be discerned, which are attributed to ontogenetic variations. A maximum‐parsimony analysis was carried out to show that the order Rhynchosauria is characterized by nine cranial and one postcranial character states. The analysis reveals that Otischalkia elderae is invalid and the basal forms, Howesia and Mesosuchus, are closely related. The Mid‐Triassic genus Ammorhynchus is more derived and forms a sister group to the Late Triassic subfamily Hyperodapedontinae. Isalorhynchus and Teyumbaita are basal to the pandemic genus Hyperodapedon. Twenty‐four characters that are not homoplasious document major patterns of skeletal evolution in rhynchosaurs. From laterally oriented scapula and slender propodials, the postcranial skeleton evolved into a more robust form as is evident from nearly vertical scapula and increase in the robustness of the propodials. Shortening of the femur is noted in the derived Late Triassic forms as exemplified in Hyperodapedon gordoni, Hyperodapedon huxleyi and H. tikiensis.     

Chromosomal characterization of Arvicanthis species (Rodentia,Murinae) from western and central Africa: implications for taxonomy

A chromosome study of unstriped grass rats of the genus Arvicanthis (Rodentia, Murinae) in western and central Africa is presented. The observations extend the data available to 242 specimens from 59 localities. All individuals karyotyped belong to four karyotypic forms, or cytotypes, earlier described as ANI-1, ANI-2, ANI-3, and ANI-4 and are presumed to correspond to four distinct species. In order to provide diagnostic characters for these western and one central African Arvicanthis species, we standardized the chromosomal data available and developed a G- and C-banded chromosome nomenclature that allows easy species identification. Each form is characterized by a distinct geographical distribution, roughly following the biogeographical domains of western Africa, although their precise limits remain to be assessed. The sole area of sympatry detected is the region of the inner delta of the Niger River, where both ANI-1 and ANI-3 can be found. It is proposed that the three western African species ANI-1, ANI-3, and ANI-4 be renamed as A. niloticus, A. ansorgei, and A. rufinus, respectively.     

Leucas pachmarhiensis sp. nov. (Lamioideae; Lamiaceae) from central India

A new species, Leucas pachmarhiensis (Lamiaceae), is described and illustrated from the Pachmarhi Biosphere Reserve, Hoshangabad district, Madhya Pradesh, India with conservation status assessed as ‘Critically Endangered’. This novelity is endemic to central India and belongs to Leucas sect. Plagiostoma. It differs from other species of this section by its height up to 120 cm, and inflorescence positioned at multiple nodes. Detailed notes on its conservation status and ecology are provided.     

Eodiaptomus shihi n. sp. (Copepoda,Calanoida) from central India

Eodiaptomus shihi n. sp. is described from the material collected from Gandhisagar reservoir, River Narmada and a hillpool in the Madhya Pradesh State of central India. The salient features of this new species include: in female, the left metasomal wing is strongly developed, and the endopodite in leg 5 is 2-segmented and longer than first exopodite-segment; in male, the right caudal ramus is armed with a tooth-like chitinous structure near ventro-distal region, and in right leg 5, the basis is devoid of any hyaline lobe on inner margin and the first exopodite-segment is produced into a large spinous process at disto-outer corner.     

Caprellids (Crustacea: Amphipoda) from India

The caprellid fauna of India is investigated. A total of 538 samples (including algae, seagrasses, sponges, hydroids, ascidians, bryozoans, encrusted dead corals, coral rubble, fine and coarse sediments) were collected from 39 stations along the coast of India, covering a wide diversity of habitats from intertidal to 12 m water depth. A new species (Jigurru longimanus n.sp.) is described, and figures of the 11 valid species reported so far from India are given together with a key for their identification. No caprellids were found in sediments from the northeast (16–20oN) coast of India while they were abundant in the southeast and west coast. Decreases in salinity due to river discharges associated with lower values of oxygen, higher water temperatures and lower nutrient inputs along the east coast could explain these differences in caprellid composition between the two coastlines. Significantly, lower abundance of caprellids in India, as in other tropical ecosystems, is probably related to the lack of species belonging to the genus Caprella, which reach very high abundances in temperate waters.     

Stable isotope analyses of belemnites from the Kachchh Basin,western India: paleoclimatic implications for the Middle to Late Jurassic transition

Stable isotope analyses of 61 diagenetically unaltered belemnite rostra from the Middle to Late Jurassic of the Kachchh Basin of western India suggest stable paleotemperatures across the Callovian-Oxfordian boundary (~14°C). Only at the end of the Middle Oxfordian water temperatures drop for more than 3°C before reaching again higher values during the Kimmeridgian (~12.3°C). The data do not support polar glaciations proposed for the Middle to Late Jurassic transition, which necessarily would have led to a global temperature and sea-level minimum at the boundary. Callovian to Oxfordian rocks in the Kachchh Basin point to a gradual shallowing corresponding to a slight fall in relative sea level. However, the magnitude of this regression is comparatively small, and the sea-level minimum is reached in the late Early Oxfordian and not close to the boundary. Results from the Kachchh Basin therefore, imply almost stable climatic conditions during the Middle to Late Jurassic transition and do not show any evidence for polar glaciations.     

Palynoflora from intertrappean localities in southeastern part of Deccan volcanic province: taxonomic composition,age and paleogeographic implications

Understanding the flora preserved in the Late Cretaceous–Early Paleocene Deccan volcanic associated sediments is significant as it gives insight into the floral composition during Deccan volcanic activity. This time interval is also associated with extinction and evolution of many angiosperm families on the Indian subcontinent. The record of palynomorph bearing intertrappean beds of Shankar Lodhi in Chandrapur district and Shimbala in Yavatmal district of Maharashtra from southeastern part of Deccan volcanic province provides information on biodiversity, age and depositional environment of the Deccan province. These intertrappean beds are characterized by presence of Maastrichtian age marker taxa such as Azolla cretacea, Jiangsupollis and Echitricolpites. Aquatic palynoassemblage such as, Azolla cretacea, Crybelosporites intertrappea, Gabonisporis vigourouxii and Sparganiaceaepollenites are dominant in Shankar Lodhi intertrappean beds. Presence of taxa Crybelosporites, Incrotonipollis and Periporopollenites in the intertrappean beds of the study area and their global geological history suggest their Gondwanan origin.     

Calcareous nannofossil surface sediment assemblages from the Sicily Channel (central Mediterranean Sea): Palaeoceanographic implications

Quantitative analysis of 67 calcareous nannofossil assemblages from surface sediments recovered in a wide area across the Sicily Channel has been carried out in order to improve the interpretation of palaeontological data based on this planktonic group in a key area for Mediterranean palaeoceanographic studies. The investigation focused on three case studies that demonstrate the high potentiality of such a combined approach, taking into account the recent distribution of taxa or groups of taxa on the sea floor and the palaeontological record. The distribution of reworked specimens over the northern Sicily Channel sea floor validates the role of southern Sicily as a source region for reworked nannofossils and the role of rivers as their carrier. Eustatic sea-level fluctuations can be considered to be the main factor that influenced the abundance variations in sedimentary sequences of this area. The distribution of Florisphaera profunda can be explained in terms of topography (positive correlation) and mesoscale oceanographic circulation. In particular, its significant anti-correlation to the amount of chlorophyll-A deduced by satellite imagery validates the use of this species as a proxy for palaeoproductivity reconstructions. Finally, high abundance values of G. oceanica are confined to the westernmost part of the Sicily Channel, coinciding with a water mass salinity minimum. In particular, abundances of up to about 10% were observed in the westernmost part of the African Margin, suggesting the importance of the Atlantic Tunisian Current, whose activity is more pronounced in winter. The comparison of data of this species between 135 and 110 kyr BP, inside and outside the Channel, led us to deduce that the physical transport in almost unmodified waters of Atlantic origin might be the most important factor for its significant occurrence.     

Bioturbational disturbance of the Cretaceous-Palaeogene (K-Pg) boundary layer: Implications for the interpretation of the K-Pg boundary impact event

Detailed field observations across and along the Cretaceous-Palaeogene (K-Pg) boundary interval in the Caravaca section, SE Spain, together with laboratory analyses reveal a well-developed lowermost Danian dark-colored trace fossil assemblage. The trace fossils range continuously from the bioturbated horizons in the dark boundary layer (lowermost Danian), to the uppermost Maastrichtian sediments. The rusty boundary layer at the base of the dark boundary layer, usually related to the K-Pg boundary impact, is traditionally considered as undisturbed. However, ichnological analysis at the Caravaca section shows that this rusty boundary layer is cross-cut vertically by Zoophycos and Chondrites, but also penetrated laterally by Chondrites, revealing an important colonization of the substrate. Stereomicroscope analysis shows sharp burrow margins of dark-colored Chondrites directly against the surrounding red sediment of the rusty layer. Colonization of unfavorable substrates by Zoophycos and Chondrites tracemakers, as that represented by the rusty boundary layer, was possible because of constructing of open, probably of actively ventilated burrows that facilitate colonization of sediments poor in oxygen and food. Significant bioturbational disturbance of the rusty layer can cause vertical and horizontal redistribution of the components related to the K-Pg boundary impact and, in consequence, to induce erroneous interpretations. A detailed ichnological analysis of the K-Pg boundary interval, with special attention to the rusty layer, reveals an essential tool to avoid misinterpretations.     

COI (cytochrome oxidase-I) sequence based studies of Carangid fishes from Kakinada coast,India

Mitochondrial DNA, cytochrome oxidase-1 gene sequences were analyzed for species identification and phylogenetic relationship among the very high food value and commercially important Indian carangid fish species. Sequence analysis of COI gene very clearly indicated that all the 28 fish species fell into five distinct groups, which are genetically distant from each other and exhibited identical phylogenetic reservation. All the COI gene sequences from 28 fishes provide sufficient phylogenetic information and evolutionary relationship to distinguish the carangid species unambiguously. This study proves the utility of mtDNA COI gene sequence based approach in identifying fish species at a faster pace.     

Drivers and spatio-temporal extent of hyporheic patch variation: implications for sampling

The hyporheic zone in stream ecosystems is a heterogeneous key habitat for species across many taxa. Consequently, it attracts high attention among freshwater scientists, but generally applicable guidelines on sampling strategies are lacking. Thus, the objective of this study was to develop and validate such sampling guidelines. Applying geostatistical analysis, we quantified the spatio-temporal variability of parameters, which characterize the physico-chemical substratum conditions in the hyporheic zone. We investigated eight stream reaches in six small streams that are typical for the majority of temperate areas. Data was collected on two occasions in six stream reaches (development data), and once in two additional reaches, after one year (validation data). In this study, the term spatial variability refers to patch contrast (patch to patch variance) and patch size (spatial extent of a patch). Patch contrast of hyporheic parameters (specific conductance, pH and dissolved oxygen) increased with macrophyte cover (r² = 0.95, p<0.001), while patch size of hyporheic parameters decreased from 6 to 2 m with increasing sinuosity of the stream course (r² = 0.91, p<0.001), irrespective of the time of year. Since the spatial variability of hyporheic parameters varied between stream reaches, our results suggest that sampling design should be adapted to suit specific stream reaches. The distance between sampling sites should be inversely related to the sinuosity, while the number of samples should be related to macrophyte cover.     

Pollen analysis of spider web samples from Korba District,Chhattisgarh (central India): an aerobiological aspect

Pollen analyses of spider web samples, collected from the recently planted Tectona grandis (T. grandis, teak)-dominated tropical deciduous forest of Bhulsidih Village, Korba District (Chhattisgarh, central India), shed light on the relationship between the extant vegetation and pollen rain. The study revealed the dominance of pollen of herbs and trees, whereas shrubs, fern spores and algal remains are meagre. Among the tree taxa, Sapotaceae, Syzygium, Holoptelea, Lannea coromandelica, Shorea robusta and Grewia are dominating with moderate to low and intermittent presence of Madhuca indica, Terminalia, Mitragyna, Schleichera, Anacardiaceae, Diospyros, Emblica officinalis and Flacourtia. However, the rest of the forest constituents are either not represented at all despite their presence in the floristics, which could be attributed to their low pollen productivity owing to entomophily as well as their poor pollen preservation pattern. On the other hand, the ground vegetation is represented by the very high frequency of grasses (Poaceae) along with Tubuliflorae, Chenopodiaceae/Amaranthaceae and Cerealia, however, Artemisia, Xanthium, Malvaceae, Caryophyllaceae and Justicia in moderate to lower values. Ferns, which occur abundantly along the adjoining stream banks, are marked by the sporadic retrieval of trilete spores that could be ascribed to the prevailing damp condition around the sampling provenance. The study, in addition to understanding the pollen–vegetation relationship, could also be helpful in aerobiological study, especially in assessing the allergenicity of various pollen grains/spores in the area of investigation, causing bronchial asthma, hay fever (allergic rhinitis/pollinosis), naso-bronchial allergy and other respiratory disorders along with conjunctivitis, contact dermatitis, eczema, food allergies and other health disorders.     

Social life of captive Asian elephants (Elephas maximus) in Southern India: implications for elephant welfare

Asian elephants in the wild live in complex social societies; in captivity, however, management often occurs in solitary conditions, especially at the temples and private places of India. To investigate the effect of social isolation, this study assessed the social group sizes and the presence of stereotypies among 140 captive Asian elephants managed in 3 captive systems (private, temple, and forest department) in Tamil Nadu, India, between 2003 and 2005. The majority of the facilities in the private (82%) and temple (95%) systems held a single elephant without opportunity for social interaction. The forest department managed the elephants in significantly larger groups than the private and temple systems. Among the 3 systems, the proportion of elephants with stereotypies was the highest in temple (49%) followed by private system (26%) and the forest department facility (6%); this correlates with the social isolation trend observed in the 3 systems and suggests a possible link between social isolation and abnormal elephant behavior separate from other environmental factors. The results of this study indicate it would be of greater benefit to elephant well being to keep the patchily distributed solitary temple and private elephants who are socially compatible and free from contagious diseases in small social groups at "common elephant houses" for socialization.     

First fossil evidence of samaras of Ventilago Gaertn. (Rhamnaceae) from India and its implications

The Ventilago Gaertn. (Rhamnaceae) is widely distributed in pantropical areas of Africa, Asia, and Australia. However, fossil records of this taxon are sparse, which limits understanding of the evolution and biogeographic history of the genus. In the present study, we report and describe two new fossil species of Ventilago, V. siwalika sp. nov. from the Miocene sediments of Himachal Pradesh, western Himalaya, and V. pliocenica sp. nov. from the Pliocene sediments of Jharkhand, eastern India based on single-winged samaras. Ventilago pliocenica is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins, the presence of equatorial rim, the hypanthium, and short pedicel. On the other hand, V. siwalika is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins. Our discovery represents the first unambiguous fossil record of single-winged samara of Ventilago from India and provides valuable insights into the evolution of this genus. In this paper, we also review its biogeographic history and add new information to understand its hypothetical migration route. Present and earlier records of Ventilago also suggest that this genus was a common forest element during Neogene (Miocene time) in Asia.     

Gregoryceras in the Oxfordian of Kachchh (India): Diverse eventful implications

The Kachchh Oxfordian ammonoid stratigraphic record for over 150 years remained restricted largely to Early Oxfordian condensed oolitic facies in the relatively distal Mainland Kachchh. Recently, it has been enlarged with the discovery in 1994 of over 200 m-thick uncondensed Middle to Late Oxfordian succession at Kantkote in the proximal part of the basin. Apart from abundant Perisphinctinae and Mayaitinae, a 10 m-thick sediment interval in the lower half of the above succession yielded a few examples of Gregoryceras. The specimens are here identified as G. gr. devauxi Bert and Enay and in view of their association with Larcheria subschilli (Lee) are assigned to the Middle Oxfordian Subschilli Horizon of the Schilli Subzone. Gregoryceras distribution south of the equator in Kachchh, Chile, Mexico and Madagascar, all within 35-40° latitude marks the southern limit of its latitudinal expansion during the first order maximum flooding surface (MFS) of the Schilli Subzone of the Kachchh Toarcian-Hauterivian Sequence. The maximum ammonoid diversity, density and frequency of the Kachchh first order sequence coupled with dominance of mayaitins and perisphinctins suggest over 20 m depth in the Gregoryceras interval. Distinctly greater bathymetry in the 200 km distally away basinal part causes sediment starved situation, and explains the Middle Oxfordian to early Early Kimmeridgian submarine nondepositional hiatus in the Mainland Kachchh.