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The first fossil species of Trichopria Ashmead, 1893 (Hymenoptera: Diapriidae) from the Miocene Zhangpu biota
No full textInternational audienceFollowing studies of the aculeate families Bethylidae, Chrysididae, Formicidae, and Apidae, we report here the Diapriidae, the fifth hymenopteran family from the middle Miocene Zhangpu amber of China. A fossil species belonging to Trichopria Ashmead, 1893 is described and figured from a male specimen. The new extinct species, Trichopria electrosinica n. sp., is characterized by the subround and hypognathous head, the flagellomeres each with 6–8 long setae, the metanotum with longitudinal keels, the petiole two times longer than wide and carinate, and the fore basitarsomere with a row of setae along the inner margin. Trichopria is one of the largest diapriid genus, with some species used in pest control program against fruit flies, but Trichopria electrosinica n. sp. is its first described fossil species. Its absence in older and long-known deposits is indicative of the disparate Diapriidae fossil record. Its occurrence in both China and Dominican Republic during the Miocene suggests that the genus was already widespread at that time
A new operational approach to multi-source landscape mapping based on radiometric information
No full textInternational audienceThis project aims to develop a methodological framework and operationalize a spatial processing chain to identify landscape units with the deployment of multi-source scales from remote sensing
Historical biogeography and systematics of yellow-bellied toads (Bombina variegata), with the description of a new subspecies from the Balkans
No full textInternational audienceThe Balkan Peninsula hosts a great proportion of Europe’s biodiversity, and this is well illustrated by amphibian richness and endemism. Among them, the yellow-bellied toad Bombina variegata has been a model in ecology and evolution, but several aspects of its phylogeography and taxonomy remain surprisingly poorly understood. In this study, we combine cytochrome b DNA barcoding data (1238 individuals from 355 localities), mitogenome phylogenetics (17.2 kb), gene-based nuclear phylogenetics (3.7 kb from four gene fragments) and multilocus phylogenomics (4759 loci / ~554 kb obtained by double digest Restriction Associated DNA sequencing; ddRAD-seq) to re-assess the diversification of B. variegata , and revisit its nomenclatural history to assign scientific names to phylogeographic lineages. The analyses support four major lineages, one assigned to B. v. variegata (Carpathians and northwestern ranges), one assigned to B. v. pachypus (Apennine Peninsula), and two assigned to B. v. scabra (Dinarides, Hellenides and Balkanides vs. the Rhodope mountains). Spatiotemporal patterns of diversification suggest a role for a Late Miocene marine incursion in the Pannonian Plain (Paratethys) as the initial trigger of divergence, followed by a vicariance event in the Apennines and a “sky island” process of Pleistocene differentiation in the Balkan Peninsula. As it reached the Dinarides during the Late Pleistocene, B. v. variegata potentially hybridized with B. v. scabra and captured its mitochondrial DNA, which resulted in a massive cyto-nuclear discordance across all northwestern European populations. Finally, we show that the two lineages of B. v. scabra significantly differ in morphology and ventral coloration patterns, and describe the Rhodope lineage as a new subspecies
Description d’une deuxième espèce pour le genre Serratochaerilobuthus Lourenço, 2024 (Scorpiones : Chaerilobuthidae)
No full textInternational audienceA new species is described for the genus Serratochaerilobuthus Lourenço, 2024. The description of this new species brings further evidence for the validity of the genus and confirms the family Chaerilobuthidae as one of the most speciose groups among those known from Early Cretaceous Burmite.Une nouvelle espèce est décrite pour le genre Serratochaerilobuthus Lourenço, 2024. La description de cette nouvelle espèce apporte un soutien supplémentaire à la validité du genre et confirme en même temps que la famille des Chaerilobuthidae est un des groupes les plus riches en espèces, parmi ceux déjà connus de l’ambre Crétacé du Myanmar
Tropical tree species with high wood specific gravity have higher concentrations of wood phosphorus, and are more efficient at resorbing it
No full textInternational audiencePhosphorus (P) and potassium (K) play important roles in plant metabolism and hydraulic balance, respectively; while Calcium (Ca) and Magnesium (Mg) are important components of cell walls. Although significant amounts of these nutrients are found in wood, relatively little is known on how the wood concentrations of these nutrients are related to other wood traits, or on the factors driving the resorption of these nutrients within stems. We measured wood nutrient (i.e., P, K, Ca and Mg) concentrations, wood specific gravity (WSG), as well as wood fiber and parenchyma fractions, in both inner (i.e., close to the pith) and outer (i.e., close to the bark) wood, for 22 tree species from a rainforest of eastern Amazonia. We first examined the associations of wood nutrient concentrations with WSG, fiber fractions and parenchyma fractions. Then, we assessed whether resorption rates (i.e., difference between heartwood and sapwood nutrient contents) differed among nutrients, and whether nutrient resorption rates were related to species ecological strategies. Wood specific gravity was unrelated to wood Ca, positively related to wood P in outer wood, and negatively related to inner wood Mg, as well as to both inner and outer wood K. Overall, nutrients were unrelated or negatively related to fiber and parenchyma fractions, except for wood Ca and wood P, which were positively related to fiber and axial parenchyma fractions in outer wood, respectively. We found that resorption rates did not differ among nutrients, and that P resorption rates was higher in high-WSG, while K, Ca and Mg resorption rates were unrelated to WSG. This study illustrates that the relationships of wood nutrient concentration with WSG and cell type fractions can be nutrient-specific. Our results indicate that, excluding a positive association between wood Ca and fiber fractions, and between wood P and axial parenchyma fractions, wood nutrients were mostly unrelated to anatomical traits. Our findings also suggest that high-WSG (i.e., shade-tolerant) species store higher amounts of wood P, and are more efficient at resorbing wood P, than low-WSG (i.e., fast-growing) species. These insights are important to increase our understanding on wood nutrient allocation, nutrient resorption, and tree ecological strategies in lowland tropical forests
Encore une nouvelle espèce pour le genre Cretaceoushormiops Lourenço, 2018 de l’ambre du Crétacé inférieur de la Birmanie (Scorpiones: Protoischnuridae)
No full textInternational audienceThe study of one new scorpion specimen from Cretaceous Burmite authorises the description of a new species of Cretaceoushormiops Lourenço, 2018 and brings further information about this genus. The new species shows quite distinct characters, particularly the confirmation of a majorante trichobothriotaxy and extremely reduced median eyes. The number of species in this genus is raised to four.L’étude d’un nouveau spécimen de scorpion de l’ambre du Crétacé inférieur du Myanmar autorise la description d’une nouvelle espèce de Cretaceoushormiops Lourenço, 2018 et apporte des nouvelles informations sur ce genre. La nouvelle espèce présente des caractères très distincts, notamment une trichobothriotaxie clairement majorante et des yeux médians extrêmement réduits. Le nombre d’espèces connues pour le genre s’élève désormais à quatre
Pleiotropic signaling of single-chain thyrostimulin (GPB5-GPA2) on homologous glycoprotein hormone receptors (ScFSHR, ScLHR, ScTSHR) in the elasmobranch Scyliorhinus canicula reproduction
No full textInternational audienceThe pituitary glycoprotein hormones (GPHs) control several physiological processes in vertebrates such as reproduction and metabolism. They include the luteinizing hormone (LH), the follicle-stimulating hormone (FSH), and the thyroid-stimulating hormone (TSH), which activate their cognate leucine-rich repeat G proteincoupled receptors (LGRs), LHR, FSHR, and TSHR. Each GPH consists of a common α subunit and a specific βFSH, βLH or βTSH subunit. More recently, two supplementary GPH proteins, GPA and GPB, were identified in nearly all bilaterians and are the ancestors of the pituitary GPH αand β-subunits, respectively. Chondrichthyans (holocephalans and elasmobranchs), the sister group of bony vertebrates, are the most ancient clade to possess diversified GPH subunits. In the present study, GPA2, GPB5, TSHβ2, but not TSHβ1, and TSHR sequences have been identified in several elasmobranch genomes, and their 3D models were analyzed. Functional hormonereceptor interactions were studied in the small-spotted catshark (Scyliorhinus canicula) and showed that conditioned media from cells expressing the recombinant single-chain ScGPB5-ScGPA2 were more effective than independent subunits in activating ScTSHR, ScFSHR, and ScLHR. Expression profiles were analyzed by real-time PCR, in situ hybridization, and immunohistochemistry along the male genital tract, other male and female tissues, and female tissues. A broader tissue distribution expression was observed for tshr and gpa2 than for gpb5, which was mainly observed in the testes. In testis, expression of tshr and gpb5 by Sertoli cells and of gpa2 by germ cells suggested paracrine/autocrine functions of GPA2/GPB5/GPHR signaling during spermatogenesis. This study complements the data on GPA2 and GPB5 by studying a chondrichthyan of phylogenetic interest for understanding the evolution of endocrine regulation in vertebrates
Integration of interculturality in education for sustainable development
No full textInternational audienceIn response to global environmental challenges, there has been a growing demand over the last century to develop the field of Education for Sustainable Development (ESD). While most research in the ESD field recognizes the importance of the cultural dimension, very few studies focus on interculturality. Despite its importance in promoting international cooperation and consensus, the development of intercultural competencies has not been consistently studied. This article examines the relationship between ESD and intercultural education by analyzing two pedagogical experiments with school groups in Guadeloupe and Quebec who worked synchronously and collaboratively on sustainable development themes. Our analysis shows that many competencies acquired during the experiments are characteristic of ESD, such as behavioral and emotional skills, including communication and empathy. This supports the idea that culture and interculturality can serve as a catalyst for ESD. Designing pedagogy based on interculturality can enhance the understanding of sustainable development issues and foster the development of crucial SD competencies