In collaboration with colleagues from around the World, a part of our research focuses on alpha taxonomy, integrative taxonomy and molecular systematics. The goal of this research focus is two-fold:
1/ Conduct fieldwork in under-explored areas to discover and sample unknown biodiversity
2/ Describe and place new taxa in a comprehensive phylogenetic framework using integrative tools and when possible next-generation molecular data
Below are some examples of groups on which we focus.
Giant ground beetles (Coleoptera, Carabidae, Carabinae)
Beetles from the subfamily Carabinae represent about 1500 species distributed across the globe. Within Carabinae, four tribes are recognized, the flightless Holarctic Cychrini (four genera, ca. 230 species), the flightless South American Ceroglossini (one genus, ca. 10 species), the flightless Pamborini (two genera, ca. 20 species), and the mostly flightless Carabini (two genera, ca. 1100 species). Within the latter, only two genera are usually recognized, the hyperdiverse genus Carabus and the Calosoma caterpillar hunter beetles. We use different clades within Carabus and Calosoma to study fine-scale phylogeographic patterns in the Alps and Pyrenees, but also important evolutionary processes involved in the loss of flight and feeding habits. These projects rely on cutting-edge phylogenomic methods including HyRAD-X, transcriptomic and whole-genome sequencing approaches.
Tiger beetles (Coleoptera, Cicindelidae)
Tiger beetles are a diverse group with >4000 described species, yet their evolutionary history remains puzzling. The main reason for this is a a lack of robust phylogenetic hypotheses for most internal clades, and the lack of accurate divergence time estimates across this family despite the existence of amber and rock fossils. Using ultraconserved elements we aim at generating robust timetrees for selected clades of tiger beetles and study they biogeography and diversification mechanisms.
Skipper butterflies (Lepidoptera, Hesperiidae)
Skippers are a diverse group of butterflies with more than 4200 species distributed across the globe. They have received comparatively low attention by molecular phylogeneticists despite intriguing ecologies and morphologies. In the framework of the ButterflyNet initiative, we investigate the phylogenetic relationships among major groups of skippers using a next-generation sequencing approach called target exon capture (anchored phylogenomics). This method allows us to capture hundreds of protein-coding gene fragments across the genome of these butterflies including museum specimens whose DNA is extracted using abdomen soak non-invasive procedures. Based on this unprecedented amount of data, we will infer a robust backbone for the skipper tree-of-life. We will also look at different intriguing groups (Baorini, Coeliadinae, Heteropterinae, Pyrrhopygini, Trapezitinae) using the same sequencing approach. We will eventually build the largest molecular tree to date for the family by assembling existing datasets and new ones in order to test evolutionary hypotheses in this fascinating group of insects.
Predaceous diving beetles (Coleoptera, Dytiscidae)
Diving beetles are a relatively diverse group of insects (> 4300 species) and some groups present a high level of cryptic diversity. They are found in a wide variety of habitats such as tropical river edges, high altitude lakes, peat swamps and even in groundwater ecosystems, canopy water tanks and waterfalls. Using the information contained in DNA sequences and in collaboration with the Balke Lab, we assess biodiversity and place new taxa in comprehensive phylogenies to understand their evolutionary ties. This area presents a high level of endemism, a threatened fauna and an alarming erosion of biodiversity mainly due to human activity. We use morphology and molecules to describe, revise and infer phylogenetic trees of diving beetles. With a highly complex geological history and an excessively large number of oceanic islands, the Australasian archipelago has been a key region to decipher evolutionary processes since the pioneer work of Alfred R. Wallace. As a result, our work mainly focuses on the emblematic islands of Australia, New Guinea and New Caledonia as long as the Wallacea region surrounding the island of Sulawesi where we aim at testing a wide range of hypotheses regarding the biogeography, diversification and ecology of these aquatic beetles using a phylogenetic framework.
Leafwing butterflies (Lepidoptera, Charaxinae)
Often, butterfly groups present very complex taxonomies due to centuries of species description by naturalists, amateurs and taxonomists, and poorly known systematics because of a lack of large-scale phylogenies. Therefore, in order to investigate the evolutionary history of several groups of brush-footed butterflies from the charismatic subfamily Charaxinae, we use freshly collected material as well as Museum specimens to build DNA matrices which serve as a starting point to test species boundaries using multiple cutting-edge species delimitation methods based on the coalescent theory. Based on the results of these analyses, we aim at building-up an exhaustive species-level sampling of multiple genera of tropical Nymphalids to infer phylogenetic relationships and test biogeographic and ecological hypotheses. At the moment we concentrate our efforts on the tribes Anaeini (Neotropics) and Charaxini (Afrotropics/Indo-Australia).