Skip to content. | Skip to navigation

Personal tools

You are here: Home

Search results

RSS Subscribe to an always-updated RSS feed.

1513 items matching your search terms.
Filter the results.
Item type



































New items since



Sort by relevance · date (newest first) · alphabetically
Article Reference Integrative taxonomy of giant crested Eusirus in the Southern Ocean, including the description of a new species (Crustacea: Amphipoda: Eusiridae)
Among Antarctic amphipods of the genus Eusirus, a highly distinctive clade of giant species is characterized by a dorsal, blade-shaped tooth on pereionites 5–7 and pleonites 1–3. This lineage, herein named ‘crested Eusirus’, includes two potential species complexes, the Eusirus perdentatus and Eusirus giganteus complexes, in addition to the more distinctive Eusirus propeperdentatus. Molecular phylogenies and statistical parsimony networks (COI, CytB and ITS2)of crested Eusirus are herein reconstructed. This study aims to formally revise species diversity within crested Eusirus by applying several species delimitation methods (Bayesian implementation of the Poisson tree processes model, general mixed Yule coalescent, multi-rate Poisson tree processes and automatic barcode gap discovery) on the resulting phylogenies. In addition, results from the DNA-based methods are benchmarked against a detailed morphological analysis of all available specimens of the E. perdentatus complex. Our results indicate that species diversity of crested Eusirus is underestimated. Overall, DNA-based methods suggest that the E. perdentatus complex is composed of three putative species and that the E. giganteus complex includes four or five putative species. The morphological analysis of available specimens from the E. perdentatus complex corroborates molecular results by identifying two differentiable species, the genuine E. perdentatus and a new species, herein described as Eusirus pontomedon sp. nov. ADDITIONAL KEYWORDS: alpha taxonomy – cryptic species – genetics – molecular systematics – phylogenetic systematics.
Located in Library / RBINS Staff Publications 2020
Proceedings Reference Intercontinental dispersal of mammals during the Paleocene new data from Europe
The Paleocene in general and in Europe in particular, is generally considered as an epoch with high endemism and few intercontinental dispersals of mammals, although some faunal interchange is known between Asia and North America, mainly from the Tiffanian-Clarkforkian boundary. Up to now, however, faunal interchange between Europe and North America during the Paleocene has almost never been demonstrated. The study of the early Paleocene fauna of Hainin (Belgium) reveals high endemism in European mammals at the end of the Danian (early Paleocene). The age of the fauna of Walbeck (Germany) is reevaluated and is likely to be Selandian (middle Paleocene), significantly older than previously suggested. Therefore, Walbeck is closer in age to Hainin than to the typical late Paleocene fauna of Cernay (France). However, the faunas from Walbeck and Cernay share many common genera that are not present in Hainin, showing a faunal turnover around the Danian-Selandian boundary in Europe, marked by the first occurrence of Plesiadapis, Arctocyon and Adunator in Walbeck, and of neoplagiaulacid multituberculates and Dissacus in Cernay. The three genera present in Walbeck are abundant and diversified in North America from the beginning of the Tiffanian, i.e., older than the expected age of Walbeck. Therefore, it is inferred that these genera dispersed from North America to Europe around the Danian–Selandian boundary, corresponding roughly to the Torrejonian–Tiffanian boundary. The absence of multituberculates in the fauna of Walbeck does not allow the drawing of definite conclusions about the moment of their dispersal, but it is likely that it happened at the same time as Plesiadapis and Arctocyon, because neoplagiaulacids are abundant and diversified during the whole Paleocene in North America. Similarly, Dissacus is very rare in Cernay, and could also have dispersed at the same time as others, but remained unnoticed because of its rarity. The Clarkforkian in North America is marked by massive arrival of taxa from Asia, among which are rodents, carnivorans, and tillodonts. The recent discovery of the latest Paleocene fauna of Rivecourt (France), where typical Paleocene taxa cohabit with rodents and a carnivoran, indicates that the large-scale dispersal event marking the Paleocene–Eocene boundary began in Europe about at the same time as in North America, with the arrival of rodents and carnivorans. The morphology of the new carnivoran species suggests that this group dispersed separately from Asia to Europe and from Asia to North America.
Located in Library / RBINS Staff Publications
Article Reference Intra- and Intertaxon stable O and C isotope variability of fossil fish otoliths: an early Eocene test case
Knowledge of basic data variability is essential for the interpretation of any proxy-based paleotemperature record. To evaluate this for δ18O stable isotope paleothermometry based on early Paleogene fish otoliths from marginal marine environments, an intra- and interspecific stable O and C isotope study was performed at a single locality in the southern North Sea Basin (Ampe Quarry, Egem, Belgium), where shallow marine sands and silts are exposed. The age of the deposits is early late Ypresian (ca. 50.9 Ma) and falls within the early Eocene climatic optimum (EECO) interval. In each of four fossiliferous levels sampled, the same three otolith species were analyzed (Platycephalus janeti, Paraconger papointi and “genus Neobythitinorum” subregularis). Intrataxon stable isotope spread amounts on average 2.50-3.00‰ for all taxa and is present in all levels. This implies that each sample level comprises substantial variability, which can be attributed to a combination of temporal and taphonomic effects. More importantly, intertaxon offsets of 4.60‰ in δ13C and 2.20‰ in δ18O between the mean values of the three otolith species are found, with “N.” subregularis representing more positive values relative to the other species. We hypothesize that freshwater influence of coastal waters is the most likely cause for these discrepancies. Similar analyses on two coastal bivalve species (Venericardia sulcata and Callista laevigata) corroborate this hypothesis. Accordingly, δ18O values measured on “N.” subregularis otoliths probably represent a more open oce- anic signal, and therefore seem well-suited for δ18O stable isotope paleothermometry. This study highlights the importance of investigating data variability of a biogenic carbonate paleotemperature proxy at the species level, before applying paleotemperature equations and interpreting the outcome.
Located in Library / RBINS Staff Publications
Article Reference Intra-specific morphological variability in the cave bear Ursus spelaeus (Mammalia, Carnivora, Ursidae) from the Trou du Sureau (Montaigle caves, Belgium) using an outline analysis
Located in Library / RBINS Staff Publications
Article Reference Introduction history and genetic diversity of the invasive ant Solenopsis geminata in the Gala´pagos Islands
The Gala´pagos Islands constitute one of the most pristine tropical systems on Earth. However, the complex and fragile equilibrium of native species is threatened by invasive species, among which is one of the most successful ants in the world, the tropical fire ant, Solenopsis geminata. We characterized the genetic structure and diversity of populations of S. geminata in the Galapagos Islands and unravelled the archipelago colonization by combining Bayesian clustering methods and coalescent-based scenario testing. Using 12 microsatellite markers and one mitochondrial DNA fragment (COI), we analysed individuals collected in all main invaded islands of the archipelago and from the native areas in Costa Rica and mainland Ecuador. We also used mitochondrial DNA to infer evolutionary relationships of samples collected in Galapagos Islands, Ecuador, Costa Rica and other Latin American countries. Our results showed that genetic diversity was significantly lower in Galapagos Islands and mainland Ecuador populations when compared to Costa Rican populations, and that samples from Galapagos Islands and mainland Ecuador (Guayaquil) clustered in a single group and all share a single mtDNA haplotype. Approximate Bayesian Computation favoured a scenario assuming that populations from Galapagos Islands diverged from mainland Ecuador. The city of Guyaquil, an obligatory hub for tourism and trade, could act as a bridgehead.
Located in Library / RBINS Staff Publications 2018
Article Reference Invasive process and repeated cross-sectional surveys of the mosquito Aedes japonicus japonicus establishment in Belgium
When accidentally introduced in a new location, a species does not necessarily readily become invasive, but it usually needs several years to adapt to its new environment. In 2009, a national mosquito survey (MODIRISK) reported the introduction and possible establishment of an invasive mosquito species, Aedes j. japonicus, in Belgium. First collected in 2002 in the village of Natoye from a second-hand tire company, then sampled in 2003 and 2004, the presence of adults and larvae was confirmed in 2007 and 2008. A repeated cross-sectional survey of Ae. j. japonicus was then conducted in 2009 in Natoye to study the phenology of the species on two different sites using three kinds of traps: Mosquito Magnet Liberty Plus traps, BG sentinel traps and CDC Gravid traps. An analysis of the blood meals was done on females to assess the epidemiological risks. Five species of mosquitos were caught using the different kind of traps: Culex pipiens, Cx. torrentium, Anopheles claviger, Aedes geniculatus and Ae. j. japonicus, Cx. pipiens being the most abundant. The CDC gravid traps gave the best results. Surprisingly Ae. j. japonicus was only found on one site although both sites seem similar and are only distant of 2.5 km. Its population peak was reached in July. Most of the engorged mosquitoes tested acquired blood meals from humans (60\%). No avian blood meals were unambiguously identified. Larvae were also collected, mostly from tires but also from buckets and from one tree hole. Only one larva was found in a puddle at 100 m of the tire storage. A first local treatment of Ae. j. japonicus larvae population was done in May 2012 using Bacillus thuringiensis subsp. israelensis (Bti) and was followed by preventive actions and public information. A monitoring is also presently implemented.
Located in Library / RBINS Staff Publications
Article Reference Investigating the co-occurrence of Neanderthals and modern humans in Belgium through direct radiocarbon dating of bone implements
Located in Library / RBINS Staff Publications 2023
Article Reference Investigating urban ant community (Hymenoptera: Formicidae) in port cities and in major towns along the border in Côte d’Ivoire: a rapid assessment to detect potential introduced invasive ant species
Objective: This study aimed at examining ant communities of port and border cities in order to identify introduced and potential invasive ant species and microhabitats likely to contribute to the spread of these ant species. Therefore, the sampling design are linear transects of 200 metres on which ants were collected using tuna baits at 15, 30, 45 and 60 minutes in the two port cities of Abidjan and San Pedro, and seven cities that are Man, Touba, Odienne, Ferkéssedougou, Bouna, Bondoukou and Abengourou located near the borders of Côte d’Ivoire. The results showed 83 ant species including 9 potential introduced or invasive ant species. These invasive ants contributed importantly to the ant assemblage in port cities (23.95±2.7 % of total richness and 37±6.1 % of total abundance) and border cities (20.17±4.7 % / 30.6±7 %). In addition two notorious invaders, Solenopsis geminata (Fabricius, 1804) (Tropical fire ant) and Pheidole megacephala (Fabricius, 1793) (Big-headed ant) were detected during this study. The results also indicated that potential introduced or invasive ant species were mostly detected in microhabitats where human activities are uninterrupted such port zones, markets, domestic streets and residential. Conclusion: In the end, this study has shown that ant communities in port and border cities harbour invasive potential ant species, particularly microhabitats characterized by high human activities such as port areas, markets, domestic streets and residential areas.
Located in Library / RBINS Staff Publications 2018
Article Reference Investigation urban ant community (Hymenoptera: Formicidae) in port cities and in major towns along the border in Côte d'Ivoire: a rapid assessment to detect potential introduced invasive ant species
Located in Library / RBINS Staff Publications 2018
Article Reference Is Lasius bicornis (Förster, 1850) a very rare ant species? (Hymenoptera: Formicidae)
Since its description based on a single alate gyne by the German entomologist Arnold Förster, Lasius bicornis (Förster, 1850), previously known as Formicina bicornis, has been sporadically observed in the Eurasian region and consequently been characterized as very rare. Here, we present the Belgian situation and we consider some explanations for the status of this species.
Located in Library / RBINS Staff Publications 2018