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Land-use conversion and resulting habitat fragmentation can affect the source(s) of primary productivity that fuels food webs and alter their structure in ways that leads to biodiversity loss. We investigated the effects of landscape modification on food webs in the Araguaia River floodplain in central Brazil using the top predator, and indicator species Caiman crocodilus (Crocodilia, Alligatoridae). We measured carbon (δ13C) and nitrogen (δ15N) isotope values of three tissues with different isotopic incorporation rates to evaluate spatial and temporal changes in caiman isotopic niche width with hierarchical Bayesian models that accounted for habitat use, intraspecific trait variation (sex and body size), and landscape attributes (composition and configuration). We also measured δ13C values of essential amino acids to assess if different primary producers are fueling aquatic food webs in natural and anthropogenic areas. Spatial analysis showed that caiman in agricultural areas had larger isotopic niche widths, which likely reflects some use of terrestrial resources in environments dominated by C4 plants. Patterns in δ13C values among essential amino acids were clearly different between natural and anthropogenic habitats. Overall, our findings suggest that caimans can persist in heterogeneous landscapes fueled by natural and agricultural energy sources of energy, which has implications for effectively managing such landscapes to maximize biodiversity.

The authors discovered a new population of Hieracium lucidum Guss., a species hitherto considered strictly endemic to Monte Gallo. Useful elements for the ecological characterisation of the new population are provided. The stretch of carbonate coastline between the Egadi Islands and the western portion of the Province of Palermo displays a very high wealth of valuable floristic elements and represents an unicum in terms of both phytogeography and ecology. Considering the extreme fragmentation of the distribution pattern of many endemic and exclusive species that characterise this district, as in the case of H. lucidum, the authors suggest upgrading the strategies to protect the local botanical heritage, going beyond the species approach and thinking on a wider territorial scale. [ABSTRACT FROM AUTHOR]

Apostolepis is a diverse genus of dipsadid snakes, currently comprising 34 species occurring in most cis-Andean South America. The taxonomy of the group is highly unstable. Upon discovering its type series, we redescribe the rare species A. ambiniger (Peters, 1869) and provide an account of its geographic distribution and morphological variation in pholidosis, osteology, and hemipenial characters. We also discuss some aspects of the taxonomy of Apostolepis.

Morphology is among the most important traits influencing the interaction of individual animals with their environments. Fossoriality reflects this functional association between morphology and the use of subterranean habitats and their associated environmental characteristics. Lizards in the families Gymnophthalmidae and Alopoglossidae are model organisms to examine the interplay between morphology and fossoriality because great morphological diversity exists among species, including varying degrees of body elongation and limb reduction, and they have a wide geographical distribution in the Neotropical region. We analysed the morphology of 101 microteiid species and created an index to evaluate their degree of fossoriality. From this index, we traced the evolution of fossoriality in these lizards and assessed its primary environmental correlates. We found that fossoriality evolved independently in several lineages, mainly associated with high temperature and low precipitation, characteristic of more arid and sandy environments. [ABSTRACT FROM AUTHOR]

Aim: The impact of climate change on biodiversity is often analysed under a stable evolutionary perspective focused on whether species can currently tolerate warmer climates. However, species may adapt to changes, and particularly under conditions of low habitat fragmentation, standing adaptive genetic variation can spread across populations tracking changing climates, increasing the potential for evolutionary rescue. Here, our aim is to integrate genomic data, niche modelling and landscape ecology to predict range shifts and the potential for evolutionary rescue. Location: The megadiverse Amazonian rainforest. Methods: We use genome–environment association analyses to search for candidate loci under environmental selection, while accounting for neutral genetic variation in a widespread Amazonian whiptail lizard (Teiidae: Kentropyx calcarata). We then model the distribution of individuals with genotypes adapted to different climate conditions. We predict range shifts for each genotype in distinct future climate change scenarios by integrating this information with dispersal constraints based on predicted scenarios of forest cover across Amazonia. The predicted ranges of each genotype were then overlapped to infer the potential for evolutionary rescue. Results: We find that the potential for evolutionary rescue and, therefore, a smaller degree of range loss buffering extinction risk in the future is considerably high, provided that current forest cover is retained and climate change is not extreme. However, under extreme environmental change scenarios, range loss will be high in central and southern Amazonia, irrespective of the degree of deforestation. Main Conclusions: Our results suggest that protecting the Amazonian rainforest against further deforestation and mitigating climate change to moderate scenarios until 2070 could foster evolutionary rescue of ectothermic organisms. These actions could prevent substantial biodiversity loss in Amazonia, emphasizing the importance of understanding species adaptability in maintaining biodiversity. [ABSTRACT FROM AUTHOR]

Abstract Ecological requirements and environmental conditions can influence diversification across temporal and spatial scales. Understanding the role of ecological niche evolution under phylogenetic contexts provides insights on speciation mechanisms and possible responses to future climatic change. Large‐scale phyloclimatic studies on the megadiverse Neotropics, where biomes with contrasting vegetation types occur in narrow contact, are rare. We integrate ecological and biogeographic data with phylogenetic comparative methods, to investigate the relative roles of biogeographic events and niche divergence and conservatism on the diversification of the lizard genus Kentropyx Spix, 1825 (Squamata: Teiidae), distributed in South American rainforests and savannas. Using five molecular markers, we estimated a dated species tree, which recovered three clades coincident with previously proposed species groups diverging during the mid‐Miocene. Biogeography reconstruction indicates a role of successive dispersal events from an ancestral range in the Brazilian Shield and western Amazonia. Ancestral reconstruction of climatic tolerances and niche overlap metrics indicates a trend of conservatism during the diversification of groups from the Amazon Basin and Guiana Shield, and a strong signal of niche divergence in the Brazilian Shield savannas. Our results suggest that climatic‐driven divergence at dynamic forest‐savanna borders might have resulted in adaptation to new environmental niches, promoting habitat shifts and shaping speciation patterns of Neotropical lizards. Dispersal and ecological divergence could have a more important role in Neotropical diversification than previously thought.

Critical and updated alien species inventories are crucial to properly manage and contrast biological invasions. After 6 years, a second update to the inventory of the vascular flora alien to Italy is presented. It provides details on the occurrence at administrative regional level and, for the first time, floristic data for San Marino. The checklist includes 1782 taxa (1673 species, 28 subspecies, 69 hybrids and 12 cultivar groups not attributable to a specific binomial), distributed in 786 genera and 159 families; 2 taxa are lycophytes, 13 ferns and fern allies, 37 gymnosperms and 1730 angiosperms. Among these, 154 taxa are archaeophytes and 1628 neophytes. The alien taxa currently established in Italy are 899 (649 naturalized and 250 invasive), while 796 taxa are casual aliens, 1 is not assessed, 38 have not been confirmed in recent times, 4 are considered extinct or possibly extinct in the country, 40 are doubtfully occurring in Italy, 4 are of unknown regional distribution and 110 are reported by mistake and to be excluded at national level. This checklist allows to establish an up-to-date number (10,023) of taxa currently constituting the whole (either native or alien) Italian flora. [ABSTRACT FROM AUTHOR]

Critical species inventories provide primary biodiversity data crucial for biogeographical, ecological, and conservation studies. After six years, a second update to the inventory of the vascular flora native to Italy is presented. It provides details on the occurrence at regional level and, for the first time, floristic data for San Marino. The checklist includes 8,241 species and subspecies, distributed in 1,111 genera and 153 families; 23 taxa are lycophytes, 108 ferns and fern allies, 30 gymnosperms, and 8,080 angiosperms. The species/subspecies endemic to Italy are 1,702, grouped in 71 families and 312 genera. The taxa currently occurring in Italy are 7,591, while 545 taxa have not been confirmed in recent times, 94 are doubtfully occurring in the country, 11 are data deficient, and 236 are reported by mistake and to be excluded at national level. Out of the 545 not confirmed taxa, 28 are considered extinct or possibly extinct. [ABSTRACT FROM AUTHOR]

Aim: Squamate fitness is affected by body temperature, which in turn is influenced by environmental temperatures and, in many species, by exposure to solar radiation. The biophysical drivers of body temperature have been widely studied, but we lack an integrative synthesis of actual body temperatures experienced in the field, and their relationships to environmental temperatures, across phylogeny, behaviour and climate. Location: Global (25 countries on six continents). Taxa: Squamates (210 species, representing 25 families). Methods: We measured the body temperatures of 20,231 individuals of squamates in the field while they were active. We examined how body temperatures vary with substrate and air temperatures across taxa, climates and behaviours (basking and diel activity). Results: Heliothermic lizards had the highest body temperatures. Their body temperatures were the most weakly correlated with substrate and air temperatures. Body temperatures of non‐heliothermic diurnal lizards were similar to heliotherms in relation to air temperature, but similar to nocturnal species in relation to substrate temperatures. The correlation of body temperature with air and substrate temperatures was stronger in diurnal snakes and non‐heliothermic lizards than in heliotherms. Body‐substrate and body‐air temperature correlations varied with mean annual temperatures in all diurnal squamates, especially in heliotherms. Thermal relations vary with behaviour (heliothermy, nocturnality) in cold climates but converge towards the same relation in warm climates. Non‐heliotherms and nocturnal species body temperatures are better explained by substrate temperature than by air temperature. Body temperature distributions become left‐skewed in warmer‐bodied species, especially in colder climates. Main Conclusions: Squamate body temperatures, their frequency distributions and their relation to environmental temperature, are globally influenced by behavioural and climatic factors. For all temperatures and climates, heliothermic species' body temperatures are consistently higher and more stable than in other species, but in regions with warmer climate these differences become less pronounced. A comparable variation was found in non‐heliotherms, but in not nocturnal species whose body temperatures were similar to air and substrate irrespective of the macroclimatic context. [ABSTRACT FROM AUTHOR]

The brown-eared woolly opossum (Caluromys lanatus) is an elusive frugivorous Neotropical canopy specialist marsupial considered primarily arboreal, but here we report the first records of individuals from this species captured on the ground in the Cerrado. We hypothesize two main reasons to explain this behavior: first related to canopy openness, which would force the animals to the ground to keep moving across the landscape; and the second related with search for food on the ground during periods of food scarcity due to increased canopy gaps. Our findings can have important implications for the species conservation and understanding forest ecological dynamics. [ABSTRACT FROM AUTHOR]