Hidden in the sand: Phylogenomics unravel an unexpected evolutionary history for the desert-adapted vipers of the genus Cerastes.

The desert vipers of the genus Cerastes are a small clade of medically important venomous snakes within the family Viperidae. According to published morphological and molecular studies, the group is comprised by four species: two morphologically similar and phylogenetically sister taxa, the African horned viper (Cerastes cerastes) and the Arabian horned viper (Cerastes gasperettii); a more distantly related species, the Saharan sand viper (Cerastes vipera), and the enigmatic Böhme's sand viper (Cerastes boehmei), only known from a single specimen in captivity allegedly captured in Central Tunisia. In this study, we sequenced one mitochondrial marker (COI) as well as genome-wide data (ddRAD sequencing) from 28 and 41 samples, respectively, covering the entire distribution range of the genus to explore the population genomics, phylogenomic relationships and introgression patterns within the genus Cerastes. Additionally, and to provide insights into the mode of diversification of the group, we carried out niche overlap analyses considering climatic and habitat variables. Both nuclear phylogenomic reconstructions and population structure analyses have unveiled an unexpected evolutionary history for the genus Cerastes, which sharply contradicts the morphological similarities and previously published mitochondrial approaches. Cerastes cerastes and C. vipera are recovered as sister taxa whilst C. gasperettii is a sister taxon to the clade formed by these two species. We found a relatively high niche overlap (OI > 0.7) in both climatic and habitat variables between C. cerastes and C. vipera, contradicting a potential scenario of sympatric speciation. These results are in line with the introgression found between the northwestern African populations of C. cerastes and C. vipera. Finally, our genomic data confirms the existence of a lineage of C. cerastes in Arabia. All these results highlight the importance of genome-wide data over few genetic markers to study the evolutionary history of species.

Evolutionary history of two cryptic species of northern African jerboas.

BACKGROUND: Climatic variation and geologic change both play significant roles in shaping species distributions, thus affecting their evolutionary history. In Sahara-Sahel, climatic oscillations shifted the desert extent during the Pliocene-Pleistocene interval, triggering the diversification of several species. Here, we investigated how these biogeographical and ecological events have shaped patterns of genetic diversity and divergence in African Jerboas, desert specialist rodents. We focused on two sister and cryptic species, Jaculus jaculus and J. hirtipes, where we (1) evaluated their genetic differentiation, (2) reconstructed their evolutionary and demographic history; (3) tested the level of gene flow between them, and (4) assessed their ecological niche divergence. RESULTS: The analyses based on 231 individuals sampled throughout North Africa, 8 sequence fragments (one mitochondrial and seven single copy nuclear DNA, including two candidate genes for fur coloration: MC1R and Agouti), 6 microsatellite markers and ecological modelling revealed: (1) two distinct genetic lineages with overlapping distributions, in agreement with their classification as different species, J. jaculus and J. hirtipes, with (2) low levels of gene flow and strong species divergence, (3) high haplotypic diversity without evident geographic structure within species, and (4) a low level of large-scale ecological divergence between the two taxa, suggesting species micro-habitat specialization. CONCLUSIONS: Overall, our results suggest a speciation event that occurred during the Pliocene-Pleistocene transition. The contemporary distribution of genetic variation suggests ongoing population expansions. Despite the largely overlapping distributions at a macrogeographic scale, our genetic results suggest that the two species remain reproductively isolated, as only negligible levels of gene flow were observed. The overlapping ecological preferences at a macro-geographic scale and the ecological divergence at the micro-habitat scale suggest that local adaptation may have played a crucial role in the speciation process of these species.

Camouflage accuracy in Sahara-Sahel desert rodents.

Camouflage helps animals to hide from predators and is therefore key to survival. Although widespread convergence of animal phenotypes to their natural environment is well-established, there is a lack of knowledge about how species compromise camouflage accuracy across different background types in their habitat. Here we tested how background matching has responded to top-down selection by avian and mammalian predators using Sahara-Sahel desert rodents in North Africa. We show that the fur colouration of several species has become an accurate match to different types of desert habitats. This is supported by a correlation analysis of colour and pattern metrics, investigation of animal-to-background similarities at different spatial scales and is confirmed by modelling of two predator vision systems. The background match was closest across large (or global) spatial scales, suggesting a generalist camouflage tactic for many background types. Some species, may have a better match to the background over small (or focal) spatial scales, which could be the result of habitat choices or differential predation. Nevertheless, predicted discrimination distances of fur colouration were virtually indistinguishable for mammalian and low for avian vision model, which implies effective camouflage. Our study provides one of the best documented cases of multilevel camouflage accuracy in geographically widespread taxa. We conclude that background matching has become an effective and common adaptation against predatory threat in Sahara-Sahelian desert rodents.

Demographic expansion of an African opportunistic carnivore during the Neolithic revolution.

The diffusion of Neolithic technology together with the Holocene Climatic Optimum fostered the spread of human settlements and pastoral activities in North Africa, resulting in profound and enduring consequences for the dynamics of species, communities and landscapes. Here, we investigate the demographic history of the African wolf (Canis lupaster), a recently recognized canid species, to understand if demographic trends of this generalist and opportunistic carnivore reflect the increase in food availability that emerged after the arrival of the Neolithic economy in North Africa. We screened nuclear and mitochondrial DNA in samples collected throughout Algeria and Tunisia, and implemented coalescent approaches to estimate the variation of effective population sizes from present to ancestral time. We have found consistent evidence supporting the hypothesis that the African wolf population experienced a meaningful expansion concurring with a period of rapid population expansion of domesticates linked to the advent of agricultural practices.

The role of climatic cycles and trans-Saharan migration corridors in species diversification: Biogeography of Psammophis schokari group in North Africa.

Highlands, hydrographic systems and coastal areas have been hypothesised to form corridors across the hyperarid Sahara desert in North Africa, allowing dispersal and gene flow for non-xeric species. Here we aim to provide a genetic test for the trans-Saharan corridor model, and predict the location and stability of ecological-corridors, by combining phylogeography and palaeoclimatic modelling. The model was the Psammophis schokari (Schokari sand racer) group, fast-moving and widely distributed generalist colubrids occurring mostly in arid and semiarid scrublands. We combined dated phylogenies of mitochondrial and nuclear markers with palaeoclimatic modelling. For the phylogeographic analysis, we used 75 samples of P. schokari and P. aegyptius, and Bayesian and Maximum-Likelihood methods. For the ecological models, we used Maxent over the distribution of P. schokari and West African lineages. Models were projected to past conditions (mid Holocene, Last Glacial Maximum and Last Inter-Glacial) to infer climatic stable areas. Climatic stability was predicted to be mostly restricted to coastal areas and not spatially continuous. A putative temporary trans-Saharan corridor was identified in Eastern Sahara, with a more stable one along the Atlantic coast. Six parapatric lineages were identified within P. schokari, four occurring in North Africa. These likely diverged during the Pliocene. The Tamanraset River might have been a vicariant agent. African lineages may have experienced further subsequent diversification during the late Pleistocene. The main P. schokari refugia were probably located along the northern margins of the Sahara, allowing its North-to-South colonization. Trans-Saharan corridors seem to have played a role in P. schokari biogeography, allowing colonization of central Saharan mountains and Sahel. Some might have worked as refugia, and even the most stable corridors may have sections working as filters, depending on each climatic phase. We expect the use of trans-Saharan corridors to decrease for more mesic species or with less dispersal capabilities.

Conquering the Sahara and Arabian deserts: systematics and biogeography of Stenodactylus geckos (Reptilia: Gekkonidae).

BACKGROUND: The evolutionary history of the biota of North Africa and Arabia is inextricably tied to the complex geological and climatic evolution that gave rise to the prevalent deserts of these areas. Reptiles constitute an exemplary group in the study of the arid environments with numerous well-adapted members, while recent studies using reptiles as models have unveiled interesting biogeographical and diversification patterns. In this study, we include 207 specimens belonging to all 12 recognized species of the genus Stenodactylus. Molecular phylogenies inferred using two mitochondrial (12S rRNA and 16S rRNA) and two nuclear (c-mos and RAG-2) markers are employed to obtain a robust time-calibrated phylogeny, as the base to investigate the inter- and intraspecific relationships and to elucidate the biogeographical history of Stenodactylus, a genus with a large distribution range including the arid and hyper-arid areas of North Africa and Arabia. RESULTS: The phylogenetic analyses of molecular data reveal the existence of three major clades within the genus Stenodactylus, which is supported by previous studies based on morphology. Estimated divergence times between clades and sub-clades are shown to correlate with major geological events of the region, the most important of which is the opening of the Red Sea, while climatic instability in the Miocene is hypothesized to have triggered diversification. High genetic variability is observed in some species, suggesting the existence of some undescribed species. The S. petrii - S. stenurus species complex is in need of a thorough taxonomic revision. New data is presented on the distribution of the sister species S. sthenodactylus and S. mauritanicus. CONCLUSIONS: The phylogenetic hypothesis for the genus Stenodactylus presented in this work permits the reconstruction of the biogeographical history of these common desert dwellers and confirms the importance of the opening of the Red Sea and the climatic oscillations of the Miocene as major factors in the diversification of the biota of North Africa and Arabia. Moreover, this study traces the evolution of this widely distributed and highly specialized group, investigates the patterns of its high intraspecific diversity and elucidates its systematics.

Hunting and persecution drive mammal declines in Iran.

The negative impacts of human activities on biodiversity are well documented. However, extinction risk studies incorporating direct human threats particularly direct killing remain limited. Here, we evaluate the potential role that direct killing through hunting and persecution, indirect human threats via land-use change, and environmental and species traits such as reproductive rate and trophic level among others, may play in driving mammal species to extinction. Based on data for 156 mammal species from Iran, we applied generalized linear models to investigate correlates of extinction risk for: (1) all mammalian species, (2) large- and (3) small-bodied species. We show that hunting vulnerability is the most important predictor to affect extinction risk across all species. We also found that the small-bodied species are impacted by indirect human influence, whereas large species are highly affected by direct killing. Overall, the extrinsic environmental factors and intrinsic species traits had lower importance in our models. Our study gives insight into the dominant role of direct killing on mammal species decline and extinction, emphasizing the need to account for the different sources of threats when analysing the correlates of extinction risk.

Assessing Asiatic cheetah's individual diet using metabarcoding and its implication for conservation.

Knowledge on diet composition allows defining well-targeted conservation measures of large carnivores. Little is known about ecology of critically endangered Asiatic cheetah, especially the overall diet and its possible regional differences. We used cheetah scats, metabarcoding technique and microsatellite markers to assess the individual and overall diet composition of the species across its entire range in Asia. Cheetahs were primarily predating on mouflon; following by ibex, cape hare and goitered gazelle. Despite their high availability, small-sized livestock was never detected. Goitered gazelles were only detected in an area where the habitat is mainly flatlands. In hilly areas, mouflon was the most frequent prey item taken. Ibex was typically taken in rugged terrain, but mouflon was still the most frequently consumed item in these habitats. High consumption of mouflon in comparison to goitered gazelle suggests that human pressure on lowland habitats has possibly forced Asiatic cheetahs to occupy suboptimal habitats where gazelles are less abundant. The protection of flatlands and the removal of livestock from them are needed to ensure the long-term survival of Asiatic cheetah. The laboratory and bioinformatics pipelines used in this study are replicable and can be used to address similar questions in other threatened carnivores.

DNA barcode reference library for the West Sahara-Sahel reptiles.

DNA barcode reference libraries are now continuously produced for the tree of life, which are essential pillars for the study of biological diversity. Yet, our knowledge about global diversity is largely limited in undersampled regions such as the largest warm desert, the Sahara-Sahel. This dataset provides a DNA barcode reference library for the reptiles of the Western Sahara-Sahel (WSS) and neighbouring countries across this region. It includes 760 barcodes from 133 reptile taxa, distributed in 23 families, and covering the intraspecific diversity of some species. A total of 84 species were collected in the WSS (83% of the total reptile species richness) over 18 overland field expeditions conducted since 2003. DNA barcodes resulted in a high success rate (95%) of species identification and barcoding gap analysis highlighted the effectiveness of the COI fragment as a barcode marker for the WSS reptiles. This dataset represents a comprehensive and reliable DNA reference library for the WSS, filling an important biodiversity gap across a remote and hard-to-sample region.

Factors That Impact the Decision to Perform Left Ventriculography in Coronary Artery Disease. / Fatores que Impactam a Decisão de Realizar Ventriculografia Esquerda em Doença Arterial Coronariana.

BACKGROUND: Left ventriculography is an invasive method for assessment of left ventricular systolic function. Since the advent of noninvasive methods, its use has been questioned, as it carries some risk to the patient. OBJECTIVE: To assess which factors are independently associated with the decision to perform ventriculography in patients with coronary artery disease. METHODS: Analytical, retrospective, database review study of electronic medical records comparing 21 predefined variables of interest among patients undergoing coronary angiography. P-values <0.05 were considered significant. RESULTS: We evaluated 600 consecutive patients undergoing coronary angiography. Left ventriculography was performed in the majority of cases (54%). After multivariate analysis, patients with chronic coronary syndrome (OR 1.72; 95% CI: 1.20-2.46; p < 0.01) were more likely to undergo the procedure. Patients with known ventricular function (OR 0.58; 95% CI: 0.40-0.85; p < 0.01); those with a history of CABG (OR 0.31; 95% CI: 0.14-0.69; p < 0.01) or hypertension (OR 0.58; 95% CI: 0.36-0.94; p = 0.02); and those with higher creatinine levels (OR 0.42; 95% CI: 0.26-0.69; p < 0.01) had greater odds of not undergoing ventriculography. CONCLUSIONS: In patients undergoing coronary angiography, a diagnosis of chronic coronary syndrome was independently associated with greater likelihood of left ventriculography, while having previously determined ventricular function, a history of hypertension or CABG, and higher creatinine levels were associated with a decreased likelihood of undergoing this procedure.

FUNDAMENTO: A ventriculografia esquerda é um método invasivo para avaliar a função sistólica do ventrículo esquerdo. Depois do advento de métodos não invasivos, o seu uso tem sido questionado por resultar em algum risco para o paciente. OBJETIVOS: Avaliar quais fatores associam-se independentemente com a decisão de realizar ventriculografia em pacientes com doença arterial coronariana. MÉTODOS: Tratou-se de um estudo analítico, retrospectivo, avaliando prontuários eletrônicos e banco de dados e comparando 21 variáveis de interesse pré-definidas entre pacientes submetidos a cineangiocoronariografia. Foi considerado significante p < 0,05. RESULTADOS: Avaliamos 600 pacientes consecutivos, e a ventriculografia esquerda foi realizada na maioria dos pacientes submetidos a uma cineangiocoronariografia (54%). Depois da análise multivariada, os pacientes com síndromes coronarianas crônicas ( odds ratio [OR] 1,72; intervalo de confiança de 95% [IC 95%]: 1,20­2,46; p < 0,01) tiveram maior chance de serem submetidos ao procedimento. Os pacientes com função ventricular conhecida (OR = 0,58; IC 95%: 0,40­0,85; p < 0,01), os revascularizados (OR 0,31; IC 95% 0,14­0,69; p < 0,01), os hipertensos (OR 0,58; IC 95%: 0,36­0,94; p = 0,02) e aqueles com maiores valores de creatinina (OR 0,42; IC 95% 0,26­0,69; p < 0,01) tiveram maior chance de não realizar ventriculografia. CONCLUSÕES: Nos pacientes submetidos a cineangiocoronariografia, o diagnóstico de síndrome coronariana crônica associou-se de modo independente com uma maior realização da técnica, enquanto ter a função ventricular previamente conhecida, ser hipertenso, ter sido submetido a revascularização cirúrgica prévia e ter valores de creatinina mais elevados associaram-se a uma maior chance de não realizar o método.

Diversity, distribution and conservation of land mammals in Mauritania, North-West Africa.

Detailed knowledge about biodiversity distribution is critical for monitoring the biological effects of global change processes. Biodiversity knowledge gaps hamper the monitoring of conservation trends and they are especially evident in the desert biome. Mauritania constitutes a remarkable example on how remoteness and regional insecurity affect current knowledge gaps. Mammals remain one of the least studied groups in this country, without a concerted species checklist, the mapping of regions concentrating mammal diversity, or a national assessment of their conservation status. This work assessed the diversity, distribution, and conservation of land mammals in Mauritania. A total of 6,718 published and original observations were assembled in a spatial database and used to update the occurrence status, distribution area, and conservation status. The updated taxonomic list comprises 107 species, including 93 extant, 12 Regionally Extinct, and 2 Extinct in the Wild. Mapping of species distributions allowed locating concentrations of extant mammal species richness in coastal areas, along the Senegal River valley, and in mountain plateaus. Recent regional extinction of large-sized Artiodactyla and Carnivora has been very high (11% extinct species). From the extant mammals, 11% are threatened, including flagship species (e.g., Addax nasomaculatus and Panthera pardus). Species richness is poorly represented by the current protected areas. Despite the strong advances made, 23% of species categorise as Data Deficient. Persisting systematics and distribution uncertainties require further research. Field surveys in currently unexplored areas (northern and south-eastern regions) are urgently needed to increase knowledge about threatened mammals. The long-term conservation of land mammals in Mauritania is embedded in a complex web of socioeconomic and environmental factors that call for collaborative action and investment in sustainable human development. The current work sets the baseline for the future development of detailed research studies and to address the general challenges faced by mammals and biodiversity in the country.

MAMMALS IN PORTUGAL: A data set of terrestrial, volant, and marine mammal occurrences in Portugal.

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications.

Assessment and prioritization of cultural ecosystem services in the Sahara-Sahelian region.

Desert environments remain largely neglected by the society and their potential to provide benefits to people remain understudied. Hotspots of cultural ecosystem services have been identified in some deserts; yet, knowing which countries need to strengthen efforts to satisfy people's demand for those services is timely needed. Here, we show the performance of countries within the Earth's largest warm region - the Sahara-Sahel - in managing cultural ecosystem services. Using the most-advanced decision-support tools and updated databases on biodiversity features and constrains to ecosystem services and on socioeconomic indicators, we identified national priorities for cultural services management. We also identified countries that are missing opportunities for local sustainable development. About 34% of Sahara-Sahel is prioritized for cultural ecosystem services, particularly in the main mountains and waterbodies of the region and along the Western and Eastern coastal limits. Algeria, Egypt, Libya, Morocco, Senegal, and Tunisia are performing better in managing their cultural services given the availability of such services in their territories. Burkina Faso, Cameroon, Chad, Egypt, Libya, Mali, Niger, Nigeria, Sudan, and South Sudan need to urgently improve their ease of mobility, governance, safety, socioeconomic and health systems to foster ecosystem services demand. Cameroon, Eritrea, and Senegal are receiving far less tourists than what their ecosystems can handle and need to improve their local conditions for better marketing international tourists able to economically contribute to sustainable development through ecotourism programs. The approach developed here serves as a framework for conserving the last world wild ecosystems and is replicable to other contexts where regional planning for ecosystem management is compulsory.

Morphology and multilocus phylogeny of the Spiny-footed Lizard (Acanthodactylus erythrurus) complex reveal two new mountain species from the Moroccan Atlas.

We generated an extensive morphological and multilocus molecular dataset to investigate the taxonomy of Acanthodactylus erythrurus, a widespread species across the Mediterranean and semiarid habitats of the Iberian Peninsula and the Maghreb. Our integrated analyses revealed the existence of at least five basal lineages: (i) an Ibero-Moroccan clade widespread across Morocco and the Iberian Peninsula, from sea-level up to a maximal known altitude of 1,930 m, (ii) an Algero-Tunisian clade, distributed in coastal and inland areas of eastern Algeria and Tunisia, (iii) a Central Algerian clade, formed by two inland populations located in central Algeria (1,000-1,500 m a.s.l.), (iv) a western High Atlas clade including two montane populations from Jbel Siroua and Tizi n'Tichka (at 2,320 m and 2,176 m a.s.l., respectively) and (v) an eastern High Atlas clade, including at least two montane populations from Isli and Tislit (both localities around 2,275 m a.s.l.). An integrated species delimitation approach combining molecular and multivariate morphological analyses demonstrated complete reproductive isolation and hence speciation between the Ibero-Moroccan clade and the eastern High Atlas clade in their contact zone. The divergence between all five clades is broadly similar, supporting the existence of at least five species in the Acanthodactylus erythrurus complex. In the present work we describe the two well-differentiated endemic species from the Moroccan Atlas for which no name is available: Acanthodactylus lacrymae sp. nov. from Isli and Tislit and A. montanus sp. nov. from Jbel Siroua and Tizi n'Tichka. Further work will be needed to fully resolve the taxonomy of this species complex.

Increase of genetic diversity indicates ecological opportunities in recurrent-fire landscapes for wall lizards.

Socioeconomic and climatic factors are modifying fire regimes with an increase of fire frequency and extension. Unfortunately, the effects of recurrent fires on biological processes that ultimately affect the genetic diversity of animal populations are mostly unknown. We examined genetic patterns of diversity in the wall lizard Podarcis guadarramae in northern Portugal, one of the European regions with the highest percentage of burnt land. This species is a small saxicolous lizard as it inhabits natural outcrops and artificial stone walls, likely in recurrent-fire landscapes. We genotyped nine microsatellites from ten populations selected according to a gradient in fire recurrence, and compared genetic diversity indexes and demographic patterns among them. At the population level, we hypothesize that a high level of mortality and population bottlenecks are expected to reduce genetic heterozygosity in sampled localities affected by recurrent fires. Alternatively, genetic signatures are expected to be absent whether fire did not cause high mortality. Regardless of levels of mortality, we expect a gain in genetic diversity whether recurrent fires facilitate lizard dispersal and migration due to the increased quality of the habitat for wall lizards. At the regional level, we examine whether a recurrent fire regime may disrupt the spatial structure of populations. Our results showed an increase in genetic diversity in recurrently burnt populations, and a decline in longer-unburnt populations. We did not detect bottleneck effects in repeatedly-burnt populations. High genetic diversity in recurrent fire populations suggests a high dispersion rate between adjacent metapopulations and perhaps immigration from outside the fire boundary. At the regional level, lizard populations show low differentiation and weak genetic structure, suggesting no effects of fire. This study confirms field-based censuses showing that recurrent-fire regimes give ecological opportunities to wall lizards that benefit from habitat openness.

Reproductive ecology of Vipera latastei, in the Iberian Peninsula: implications for the conservation of a Mediterranean viper.

Eurosiberian vipers have been considered model organisms, and studies on their reproductive ecology have afforded much of the current knowledge concerning viviparity in snakes. However, such studies are biased towards northern species and there is little information on Mediterranean species and/or populations. The reproductive ecology of Vipera latastei in the Iberian Peninsula was studied by analysing a large sample of specimens from collections, to better understand the conservation status of this Mediterranean viper. Males and females matured at small and similar body sizes (240 and 265 mm snout-vent length, respectively) and reproductive cycles in both sexes were seasonal. Spermatogenesis peaked in August, vitellogenesis developed in spring and the timing of the mating period was puzzling, with populations mating in autumn, spring, or in both seasons. The most striking finding was that adult females reproduced triennially on average. Lataste's viper is currently in continuous decline in the IP, and most of its populations are isolated in Mediterranean mountains. We hypothesize that prey scarcity and the brevity of the activity period in mountain habitats diminishes the ability of vipers to recover over the short term the energy expended in reproduction. The species needs 2 years for the acquisition and storage of energy ("capital breeder"), and a third year for the expenditure of this energy (in vitellogenesis and embryogenesis), a year during which females feed consistently ("income breeder"). Thus, this viper combines both strategies to supply the reproductive energy cost. Current decline in population and distribution, together with a poor capacity to renew populations, renders Lataste's viper vulnerable to environmental stochasticity.

Fatores que Impactam a Decisão de Realizar Ventriculografia Esquerda em Doença Arterial Coronariana / Factors That Impact the Decision to Perform Left Ventriculography in Coronary Artery Disease

Resumo Fundamento A ventriculografia esquerda é um método invasivo para avaliar a função sistólica do ventrículo esquerdo. Depois do advento de métodos não invasivos, o seu uso tem sido questionado por resultar em algum risco para o paciente. Objetivos Avaliar quais fatores associam-se independentemente com a decisão de realizar ventriculografia em pacientes com doença arterial coronariana. Métodos Tratou-se de um estudo analítico, retrospectivo, avaliando prontuários eletrônicos e banco de dados e comparando 21 variáveis de interesse pré-definidas entre pacientes submetidos a cineangiocoronariografia. Foi considerado significante p < 0,05. Resultados Avaliamos 600 pacientes consecutivos, e a ventriculografia esquerda foi realizada na maioria dos pacientes submetidos a uma cineangiocoronariografia (54%). Depois da análise multivariada, os pacientes com síndromes coronarianas crônicas ( odds ratio [OR] 1,72; intervalo de confiança de 95% [IC 95%]: 1,20-2,46; p < 0,01) tiveram maior chance de serem submetidos ao procedimento. Os pacientes com função ventricular conhecida (OR = 0,58; IC 95%: 0,40-0,85; p < 0,01), os revascularizados (OR 0,31; IC 95% 0,14-0,69; p < 0,01), os hipertensos (OR 0,58; IC 95%: 0,36-0,94; p = 0,02) e aqueles com maiores valores de creatinina (OR 0,42; IC 95% 0,26-0,69; p < 0,01) tiveram maior chance de não realizar ventriculografia. Conclusões Nos pacientes submetidos a cineangiocoronariografia, o diagnóstico de síndrome coronariana crônica associou-se de modo independente com uma maior realização da técnica, enquanto ter a função ventricular previamente conhecida, ser hipertenso, ter sido submetido a revascularização cirúrgica prévia e ter valores de creatinina mais elevados associaram-se a uma maior chance de não realizar o método.

Abstract Background Left ventriculography is an invasive method for assessment of left ventricular systolic function. Since the advent of noninvasive methods, its use has been questioned, as it carries some risk to the patient. Objective To assess which factors are independently associated with the decision to perform ventriculography in patients with coronary artery disease. Methods Analytical, retrospective, database review study of electronic medical records comparing 21 predefined variables of interest among patients undergoing coronary angiography. P-values <0.05 were considered significant. Results We evaluated 600 consecutive patients undergoing coronary angiography. Left ventriculography was performed in the majority of cases (54%). After multivariate analysis, patients with chronic coronary syndrome (OR 1.72; 95% CI: 1.20-2.46; p < 0.01) were more likely to undergo the procedure. Patients with known ventricular function (OR 0.58; 95% CI: 0.40-0.85; p < 0.01); those with a history of CABG (OR 0.31; 95% CI: 0.14-0.69; p < 0.01) or hypertension (OR 0.58; 95% CI: 0.36-0.94; p = 0.02); and those with higher creatinine levels (OR 0.42; 95% CI: 0.26-0.69; p < 0.01) had greater odds of not undergoing ventriculography. Conclusions In patients undergoing coronary angiography, a diagnosis of chronic coronary syndrome was independently associated with greater likelihood of left ventriculography, while having previously determined ventricular function, a history of hypertension or CABG, and higher creatinine levels were associated with a decreased likelihood of undergoing this procedure.