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Aim India is dominated by tropical grassy biomes (TGBs), traditionally considered seres or degraded forest, with low diversity relative to the restricted, ancestral wet zone. It is unclear if Indian grasslands and other open habitats are anthropogenically derived or native, old-growth habitats; without a clear timescale of grassland evolution. One way to understand grassland evolution is to study the diversification in taxa restricted to open habitats. We use a dated phylogeny of Ophisops to address questions related to the origin, diversification and inter-relationships of Indian and Saharo-Arabian Ophisops, and ultimately the origin of Indian grasslands and open habitats. Location The Indian subcontinent; the Saharo-Arabian Realm. Methods We generated up to 2736 base pairs of aligned sequence data (one mitochondrial, two nuclear genes) for Indian lacertids and reconstructed phylogenetic relationships using maximum likelihood and Bayesian inference. We use a fossil-calibrated timetree, diversification analyses and ancestral area reconstructions to test the hypotheses of origin and relationships with Saharo-Arabian Ophisops. Results Ophisops is strongly supported as monophyletic, with a basal split into a large-bodied (LBC) and small-bodied clade (SBC). The Saharo-Arabian species are nested within the Indian species in the LBC. Species diversity in Indian Ophisops is grossly underestimated, with 26–47 candidate species. Ophisops began diversifying in the late Oligocene with significant rate shifts in the late Miocene-Pliocene and Pleistocene within the SBC. Main conclusions Our results are consistent with an ancient origin of grassland taxa and TGBs in India. Ophisops is a dramatic example of overlooked cryptic diversity outside forests, with ~30 species where five were known. Ophisops dispersed into India from the Saharo-Arabian Realm in the Oligocene with a back dispersal in the Middle Miocene, a novel biogeographical pattern. Diversification in the SBC of Ophisops increased 8-fold during the global C4 grassland expansion. Indian TGBs are old-growth ecosystems that need urgent conservation attention.

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Relationships of lacertid lizards were assessed on the basis of 84 primary and 112 binary characters drawn mainly from morphology, including features of the skeleton, external anatomy, various internal soft part systems and two aspects of behaviour. Among features not previously used, or not fully investigated before, are structure of the septomaxilla and nasal passages, arranged of the xiphisternal cartilages, mite pockets, kidney position, ulnar nerve arragement, thoracic fascia, aspects of the hemipenis and its associated muscles, female genitalia and jaw muscles. On the basis of parsimony analysis and compatibilty treatment of this character set, the Lacertidae fall into two main portions: A paraphyletic Palaearctic and Oriental group of primitive forms, from which is derived a holophyletic assemblage of Ethiopian and advanced Saharan and Eurasian taxa. The former group ist not fully resolvable, but Psammodromus and Gallotia appear to be sister groups and are probably related to Lacerta parva and L. fraasi and then L. brandtii, Podarcis appears to be related successively to L. andreanszkyi, the sister species L. dugesii and L. perspicillata, and perhaps L. danfordi and L. laevis. This assemblage may be related to archaeolacertas and Algyroides. The separation of Lacerta lepida, L. pater and L. princeps from the agilis group, based on chemical evidence, is weakly contradicted by morphology. Takydromus may be most closely related to L. vivipara, and L. jayakari and L. cyanura constitute the most likely sister group of the Ethiopian and advanced Saharo-Eurasian assemblage. Taxe in the Ethiopian and advanced SaharoEuroasian assemblage form a long essentially pectinate tree with relatively change between the side branches, except for a strong disjunction separating the more primitive from the more advanced taxa. Most of the former fall on two main branches, with ´Lacerta` australis and ´L.` rupicola possibly basal to them. 1. the Equatorial forest group containing Gastropholis, Bedriagaia, ´Lacerta` echinata, Adolfus, ´Lacerta` jacksoni and Holaspis. The first three of these constitute a holophyletic group and the same is probably true of the remainder. 2. Tropidosaura, Poromera and Nucras, the latter being the sister group of the more advanced forms. These include successively the Ethiopian Philochortus, Latastia, Ichnotropis and Heliobolus, Pseuderemias, Meroles and Aporosaura, and Pedioplanis, and then the Saharo-Eurasian Eremias, Acanthodactylus, Mesalina and Ophisops-Cabrita. It seems probable that the ancestors of modern Lacertidae arose in western Eurasia, where the family is known since the Palaeocene and is still represented there largely by quite primitive forms (89 species and seven nominal genera). The family later invaded Africa, perhaps first in the early or middle Miocene. Relatively primitive lacertids spread widely in largely mesic situations in the Ethiopian region, radiating to some extent (six present genera and 16 species) and producing Nucras and the related series of advaned groups (eight genera and 54 species) whoich show increasing adaptation to xeric environments. These genera tend to have heir most primitive species in the northeast and north of the Ethiopian region. The most advaned gave rise to the Saharo-Eurasian clade, now made up to Eremias, Acanthodactylus, Mesalina and Ophisops-Cabrita. This invaded the arid areas of North Africa and Eurasia, where it is presently represented by 70 species. Many morphological changes in increasingly advanced lacertids may be functionally related to the problems of survival in arid, hot, open environments. Considerable ecological parallelism exists in lacertids, with members of separate stocks occupying similar niches in different geographical areas. Morphological adaptations associated with these niches contribute significantly to the high levels of character homoplasy found in the family. There is also some correlation between the degree of niche differentiation in various groups and the quality of the phylogenies that can be produced from their physical characters. A number of morphological parallels exist between advaned lacertids and New World macroteiids. In the skull at least, advaned lacertids show a complex mixture of paedomorphosis and acceleration. Nomenclatorial changes are as follows: Cabrita is synonymised with Ophisops, necessitating a new name, Ophisops nictans, for Cabrita jerdonii. Aporosaura is synonymised with Meroles, Platyplacopus with Takydromus, and Bedriagaia with Gastropholis. ´Lacerta` (or Centromastyx) echinata is also transferred to the latter genus and Lacerta jacksoni to Adolfus. ´Lacerta` australis and ´L.` rupicola are put in a new genus, Australolacerta. It is recommended that Lacerta dugesii and L. perspicillata should not be placed in the otherwise very uniform genus Podarcis. Although clearly paraphyletic, Lacerta s. lat. Should be retained at least for the present and, if necessary putative relationships within it indicated by informal groups or subgenera.

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Differences in surface structure (ober- hautchen) of body scales of lacertid lizards involve cell size, shape and surface profile, presence or absence of fine pitting, form of cell margins, and the occurrence of longitudinal ridges and pustular projections. Phylogenetic information indicates that the primitive pattern involved narrow strap-shaped cells, with low posteriorly overlapping edges and relatively smooth surfaces. Deviations from this condition produce a more sculptured surface and have developed many times, although subsequent overt reversals are uncommon. Like variations in scale shape, different patterns of dorsal body microornamentation appear to confer different and conflicting performance advantages. The primitive pattern may reduce friction during locomotion and also enhances dirt shedding, especially in ground-dwelling forms from moist habitats. However, this smooth microornamentation generates shine that may compromise cryptic coloration, especially when scales are large. Many derived features show correlation with such large scales and appear to suppress shine. They occur most frequently in forms from dry habitats or forms that climb in vegetation away from the ground, situations where dirt adhesion is less of a problem. Microornamentation differences involving other parts of the body and other squamate groups tend to corroborate this functional interpretation. Microornamentation features can develop on lineages in different orders and appear to act additively in reducing shine. In some cases different combinations may be optimal solutions in particular environments, but lineage effects, such as limited reversibility and different developmental proclivities, may also be important in their genesis. The fine pits often found on cell surfaces are unconnected with shine reduction, as they are smaller than the wavelengths of most visible light.

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We examined the distribution pattern, across-site similarities and zoogeographic affinities of amphibians and reptiles in the montane zones (> 900 m a.s.l.) of the Southern Eastern Ghats mountains in peninsular India. We deployed long-term field surveys in four select massifs namely Jawadi, Shevaroys, Kolli and Sirumalai and generated herpetofaunal species lists. Based solely on our species occurrence data, we identified taxa that characterise sites, site-pairs and site-clusters. We quantified the number of the various target taxa characterising each such Operational Geographic Unit. To infer faunal similarities, we performed cluster analysis using Jaccard’s similarity index. Our cluster diagram tree topologies differed between the various target taxa. The pooled data (amphibians, lizards and snakes) tree topology was similar to that of the lizard trees but the amphibian- and snake-similarity trees were similar in their topologies. Our observations and analyses indicate that physical separation distance and intervening rivers between massifs decreased herpetofaunal similarity. To identify the zoogeographic affinities of range-restricted taxa, we segregated the species into classes, based on decreasing extent of their geographic ranges. Our analyses reveal that widespread species were predominant in this community even at high elevations, followed by Western Ghats dispersers, Eastern Ghats endemics (both presumed and confirmed), and lastly peninsular Indian and Sri Lankan elements.

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We examined the amphibian and squamate reptilian species richness of Southern Eastern Ghats based on a long term-field survey with nearly two years of field days. We surveyed high elevation slopes (>900 m a.s.l.) of four select hill ranges namely Jawadi, Shevaroys, Kolli, and Sirumalai hills which comprehensively represented full geographical and spatial coverage. We present a descriptive species-account with basic morphological data sup- ported by voucher photographs. We summarize the history of herpetological explorations in this landscape and also comment on some of the major previous works in the region. Our study revealed the presence of 62 species in the montane zones, including 32 (51%) new records involving all the three target taxa (frogs, lizards and snakes) and all the four hill ranges that testify the poor knowledge on the region’s herpetofauna till date. Lastly, we remark on the unresolved taxonomic status of some species recorded in the present study. We recommend specimen-based revisionary works in the nearby Western Ghats, where such taxa are much more diverse, to enable taxonomic stud- ies in this region.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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We present an inventory of the herpetofauna of the Nallamala Hills, Eastern Ghats, south-eastern India. The fauna, as currently known, includes 20 species of amphibians belonging to 14 genera in six families and 64 species of reptiles belonging to 42 genera in 15 families. Divided in habitat types, the herpetofauna can be classified into species tolerant of disturbed habitats; exclusively scrub species (and for reptiles, from rocky biotopes); scrub and bordering agricultural fields; and exclusively mesic forest species. For one species, lack of ecological information precludes its allocation to a specific habitat category. Significant diversity of squamates (including gekkonids, scincids, and colubrids) are known from these ranges, several of which endemic or largely restricted to scrub forests of Peninsular India. Mesic forests remain poorly explored, and support hitherto undescribed species among the herpetofauna. Adaptations seen amongst the herpetofauna of the Nallamala Hills include a diversity of dietary and habitat types, including, among amphibians, ant specialists; predators of small vertebrates; folivores; fossorial; terrestrial; aquatic or aquatic-margin; and arboreal forms. Amongst reptiles, adaptive types includes ant- and worm-eaters; predator of crop pests; predator of small or medium-sized vertebrate prey; egg-predators; fish-eaters; frog- and toadeaters; and one near-exclusive snake-eater. In terms of habitat usage, reptiles exceed amphibians in species richness, on account of their greater capacity of surviving in relatively arid regions. The Eastern Ghats contributes significantly to both species richness and endemicity of the Indian region, including representatives of endemic genera and species. Nonetheless, these hills continue to receive less attention for conservation compared to the relatively better-known Western Ghats.

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The aim of this study was to determine if divergence in habitat use among lacertid lizards is paralleled by morphological differentiation. For 35 lacertid species, we measured body, head and limb dimensions. Habitat use was inferred from the literature: ground-dwelling on open terrain, ground-dwelling in vegetated areas, shrub-climbing, tree-climbing, saxicolous (i.e. rock-climbing). Traditional (i.e. non-phylogenetic) statistical analyses suggest morphological differences among species groups with different habitat use. Ground-dwelling species from open habitats tend to have longer femurs, tibiae and humeri (relative to body length) than other groups. Cursorial (i.e. level-running) species have relatively high heads and trunks compared to climbing species. These differences follow biomechanical predictions and it is tempting to consider tham as adaptations to habitat use. However, phylogenetic analyses of the data fail to establish a clear relationship between habitat use and morphology in the data set considered. There is a weak indication that the differences in head and trunk height have evolved as an adaptation to different habitat use, but the differences in relative limb dimensions among species groups with different habitat use vanish. Either adaptation of limb dimensions to habitat use has not occurred in lacertid lizards, or our methods are unable to demonstrate such an adaptation. We show that uncertainties in the topology of the phylogenetic tree used are unlikely to influence the outcome of our study. We also address the fact that habitat use is often similar in different branches of the phylogenetic tree, and the consequences this may have for the power of our statistical analyses.

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Over the past two decades many checklists of reptiles of India and adjacent countries have been published. These publications have furthered the growth of knowledge on systematics, distribution and biogeography of Indian reptiles, and the field of herpetology in India in general. However, the reporting format of most such checklists of Indian reptiles does not provide a basis for direct verification of the information presented. As a result, mistakes in the inclusion and omission of species have been perpetuated and the exact number of reptile species reported from India still remains unclear. A verification of the current listings based on distributional records and review of published checklists revealed that 199 species of lizards (Reptilia: Sauria) are currently validly reported on the basis of distributional records within the boundaries of India. Seventeen other lizard species have erroneously been included in earlier checklists of Indian reptiles. Omissions of species by these checklists have been even more numerous than erroneous inclusions. In this paper, I present a plea to report species lists as annotated checklists which corroborate the inclusion and omission of species by providing valid source references or notes.