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Landmark-based Principal Component Analysis was performed on multiple phytosaur and crocodilian skulls. Multiple landmark points were selected defining suture points of bone tissues and regions of maximum or minimum curvature along the skull. Scatter plots of the principal component scores show that phytosaurs cluster according to their higher order taxonomic groups, and the convex hull polygons of the different clades occupy distinct morphospaces albeit with variable degrees of overlap. Disparity between the morphospaces of non-Mystriosuchinae parasuchids and Mystriosuchinae phytosaurs suggests marked differences in skull shape among basal and derived taxa. The vector deformation plots of phytosaur skulls showcase the evolution of skull shape from basal to advanced forms. The morphological changes imply evolution of the phytosaur skulls towards a wider and deeper snout, cage-like grip, tendency for increasing jaw strength, and faster-snapping action. In addition, heightening of the nostrils suggested that phytosaurs evolved into ambush predators, and increased their ability to remain submerged underwater with their nostrils high above the water surface, thereby enhancing their ability to ambush prey. The study supports prior assumptions of dietary preferences among the phytosaurs and maps the evolution and prevalence of cranial morphotypes, associated with such dietary preferences, across the different phytosaur clades. [ABSTRACT FROM AUTHOR]

Detailed description and phylogenetic assessment of a phytosaur skull collected from the Tiki Formation of the Rewa Gondwana Basin of India and earlier diagnosed as Parasuchus hislopi, show that it pertains to a new genus and species, Volcanosuchus statisticae. The new taxon is characterized by marginal overlapping of the nostrils by the antorbital fenestrae, external nares situated on a bulbous and raised dome, the lateral surface of the jugal ornamented by a prominent ridge defined by multiple tubercles and radiating thread‐like structures, and distinct ornamentation patterns on the rostrum and skull table. Phylogenetic analysis nests Volcanosuchus within Mystriosuchinae, where it forms a sister taxon to (Rutiodon + Leptosuchomorpha) and marks the transition between the basal Parasuchidae and more derived Mystriosuchinae phytosaurs. Evolution of the phytosaur skulls resulted in changes from non‐overlapping nostril and antorbital fenestra to an overlapping state, anteroposterior elongation of the exoccipital–supraoccipital shelf, appearance of a median ridge on the basioccipital, and reduction of the supratemporal fenestra. Considerable faunal overlap of the Tiki Formation is evident with the lower Maleri Formation, which is late Carnian based on the occurrence of Hyperodapedon, Parasuchus and Exaeretodon. The Tiki Formation correlates with the Ischigualasto Formation of Argentina, the upper part of the Santa Maria Formation, and the overlying lower Caturrita Formation of Brazil, the Isalo II Beds of Madagascar, Lossiemouth Sandstone of Scotland, and the lower Tecovas Formation of the Chinle Group of North America, and ranges from late Carnian to early/middle Norian. [ABSTRACT FROM AUTHOR]

Numerous isolated teeth recovered from the Upper Triassic Tiki Formation of India have high, cylindrical, triangular to conical crowns with serrated mesial and distal carinae, and oval/subcircular and elliptical crown bases. Within this overall morphology, the teeth are subdivided into six morphotypes based on crown proportions, nature of carinae and serration and crown-base ratios. These ziphodont teeth are compared with those of other dominant Late Triassic carnivores of India to show similarity with that of the phytosaurs based on their shape, recurved nature, crown proportions, the presence of carina(e), nature of serrations and serration density. The different morphotypes reflect positional heterodonty, and three upper jaw dental sets are identified. This finding is corroborated by PCA, where the morphotypes form distinctly separate clusters, though partial overlapping of these convex hull polygons suggests that these teeth belonged to a single phytosaur taxon. As tripartite dentition is a derived condition; it may be concluded that these isolated teeth belonged to a more derived phytosaur, yet to be recovered from the Tiki Formation. The study highlights the importance of examining isolated teeth in order to identify the fossil forms which are yet to be discovered. [ABSTRACT FROM AUTHOR]

The introduction of the Joint Forest Management (JFM) programme in India as a part of community forestry initiatives from the late 1980s was an internationally recognised successful effort in forest restoration. Its achievements were most pronounced in the Sal (Shorea robusta)-dominated tropical dry deciduous forests of eastern and south-eastern states of India. However, these forests, and consequently the marginal people dependent on them for their livelihood, have increasingly faced multidimensional challenges in the past 15 years in the context of sustainable forest management. An overall assessment of the management scenario for these community forests and formulation of some guidelines towards better management was carried out on the basis of intensive case studies in the Nayagram Forest Range of West Bengal, India. Socio-economic as well as ecological aspects of sustainable forestry were analysed on the basis of criteria and indicators of community-oriented forestry. Functioning of a forest protection community as a cohesive group was found to be the major determinant in achieving sustainability in forest management. Maintenance of such institutional sustainability is recommended for better conservation of these highly stressed forest lands. [ABSTRACT FROM PUBLISHER]