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Our knowledge of the conservation status of reptiles, the most diverse class of terrestrial vertebrates, has improved dramatically over the past decade, but still lags behind that of the other tetrapod groups. Here, we conduct the first comprehensive evaluation (~92% of the world's ~1714 described species) of the conservation status of skinks (Scincidae), a speciose reptile family with a worldwide distribution. Using International Union for Conservation of Nature (IUCN) criteria, we report that ~20% of species are threatened with extinction, and nine species are Extinct or Extinct in the Wild. The highest levels of threat are evident in Madagascar and the Neotropics, and in the subfamilies Mabuyinae, Eugongylinae and Scincinae. The vast majority of threatened skink species were listed based primarily on their small geographic ranges (Criterion B, 83%; Criterion D2, 13%). Although the population trend of 42% of species was stable, 14% have declining populations. The key threats to skinks are habitat loss due to agriculture, invasive species, and biological resource use (e.g., hunting, timber harvesting). The distributions of 61% of species do not overlap with protected areas. Despite our improved knowledge of the conservation status of the world's skinks, 8% of species remain to be assessed, and 14% are listed as Data Deficient. The conservation status of almost a quarter of the world's skink species thus remains unknown. We use our updated knowledge of the conservation status of the group to develop and outline the priorities for the conservation assessment and management of the world's skink species. © 2021 Elsevier Ltd

Few published data are available on West African Agamid lizards. From 2003 to 2009, we have collected 1,020 specimens from 11 countries (Senegal, Mauritania, Mali, Guinea, Liberia, Burkina Faso, Ghana, Togo, Benin, Niger, Nigeria) and investigated their systematics, geographic distribution, ecology and phylogeny. For molecular studies, we have used two separate portions of mitogenome, coding for 16S rRNA and for cytochrome B. DNA from 100 mg of homogenized muscular tissue conserved in ethanol, was extracted using the QIAGEN BioRobot MDx Workstation with customized extraction protocol and stored at 4°C until use in PCR amplifications. Primers were manufactured by Eurogentec, Seraing, Belgium. Polymerase chain reactions were performed in automated DNA thermal cyclers. PCR products were visualized by electrophoresis on a 1.5% agarose gel, stained with ethidium bromide and examined using an ultraviolet transilluminator. The PCR products were purified using a QIAquick Spin PCR Purification Kit (Qiagen) according to the manufacturer's instructions. Sequencing of amplicons was performed using the BigDye Terminator Cycle Sequencing Kit with ABI automated sequencer. Obtained sequences were assembled, edited by BioEdit Sequence alignment editor v. 7.0.9.0 and compared with those available in GenBank by NCBI BLAST. Sequences of both mitochondrial genes from studied lizards were concatenated and aligned with CLUSTAL W program, and a neighbor-joining phylogenetic tree was constructed with Geneious 4.7.6 software. Fourteen different species were recognized in the genus Agama in West Africa, excluding the easternmost part of Nigeria near the Cameroon border which was not included in our study: Agama africana, A. agama, A. boueti, A. boulengeri, A. castroviejoi, A. cristata, A. doriae benueensis, A. gracilimembris, A. insularis, A. paragama, A. sanka-ranica, A. weidholzi, and two undescribed species. According to biogeographic areas, four species were Sahelian, seven species were Sudanian, two species were Guinean, and one species was ubiquitous.

A comparative study between the Enzyme-Linked Immuno Sorbent Assay (ELISA-CSP) for circumsporozoitic antigen detection method, the direct observation after dissection and the polymerase chain reaction (PCR) technique used to identify Plasmodium falciparum genomic DNA markers was carried out. This to evaluate the sensibility and the specificity of the PCR, for the determination of both sporozoitic index (ICSP) and the entomological inoculation rate (EIR). The study is conducted in laboratory on eighty six specimens of Anopheles gambiae M infected after being fed with the blood of a gametocytes carrier from Dielmo (Senegal). Salivary glands of forty-eight specimens randomly selected (test A) among the infected eighty six are microscopically observed after manual dissection for the sporozoites detection. The content of these salivary glands and the crushed head/thorax of the remaining 38 specimens (test B) are tested in ELISA-CSP and PCR. The positive and negative results obtained were recorded and summarized for each method. A pair-comparison of the results obtained with each method generally revealed a good sensibility and an excellent specificity. The kappa coefficient (K) of test A indicated a "moderate" to "excellent" concordance between the three different methods performed. By using the crushed head/thorax sample, generally used to determine the transmission parameters (ICSP and EIR), the PCR / ELISA-CSP concordance was excellent. In the light of the values of sensibility and specificity obtained, this PCR is comparable to the other methods for the assessment of sporozoitic index and entomological inoculation rate.; Une étude comparative entre la méthode immuno-enzymatique de détection de l'antigène circum-sporozoïtique (ELISA-CSP), l'observation directe après dissection et la technique d'amplification en chaîne (PCR) d'un marqueur génomique de Plasmodium falciparum a été menée. Ceci pour évaluer la sensibilité et la spécificité de la PCR comme une autre méthode de détermination de l'indice sporozoïtique (ICSP) des anophèles et du taux d'inoculation entomologique (EIR). L'étude est réalisée en laboratoire sur 86 spécimens d'Anopheles gambiae M infectés après alimentation avec le sang d'un porteur de gamétocytes originaire de Dielmo (Sénégal). Les glandes salivaires de 48 spécimens pris au hasard sur les 86 sont observées au microscope pour la recherche de sporozoïtes (test A). Leurs contenus ainsi que les broyats de tête/thorax des 38 échantillons restants (test B) sont utilisés pour l'ELISA-CSP et la PCR. Les résultats positifs et négatifs obtenus avec chacune des techniques sont comparés par paires. Généralement, une bonne sensibilité et une excellente spécificité sont obtenues. Le coefficient kappa () montre une concordance, variant de modérée à excellente, entre les différentes techniques utilisées dans le test A. Avec le broyat tête/thorax, généralement utilisé pour la détermination des indicateurs de la transmission, la concordance entre la PCR et l'ELISA-CSP est excellente. Au vu des valeurs de sensibilité et de spécificité obtenues, cette PCR est comparable aux autres méthodes pour la détermination de l'indice sporozoïtique et le taux d'inoculation entomologique.

Epidemiological studies, based on longitudinal surveys of human communities from endemic areas of Senegal and Brazil, have provided more precise criteria for defining premunition. Humoral and cellular immune responses of individuals with different levels of premunition have been investigated using recombinant antigens and peptides corresponding to vaccine-candidate antigens. (Résumé d'auteur)