Search results for "ASTER"
showing 10 items of 2223 documents
Nomenclatural synopsis of cirsium sect. Eriolepis (asteraceae) in Italy
2021
The names of the Italian taxa in Cirsium sect. Eriolepis are discussed. The accepted names are: Cirsium echinatum, C. eriophorum subsp. eriophorum, C. eriophorum subsp. spathulatum, C. ferox, C. italicum, C. lacaitae, C. lobelii, C. morisianum, C. scabrum, C. tenoreanum, C. vallis-demonii subsp. vallis-demonii, C. vallis-demonii subsp. calabrum comb. nov., and C. vulgare (= C. crinitum, C. sylvaticum). Four accepted names are typified by specimens preserved at FI (one lectotype), G (one lectotype and one neotype), P (one lectotype), and by illustrations (two lectotypes). Several other heterotypic synonyms of taxa described from Italy are discussed and six of them are typified. A new combina…
A note on leaf venation and the circumscription of Tephroseris (Asteraceae–Senecioneae)
2020
Molecular phylogenetic results had shown that Tephroseris, a genus differentiated from its closest relatives by its pinnately veined leaves, also contains species with palmate leaf venation. This had led to the conclusion that leaf venation is a homoplasious character in the lineage containing Tephroseris. We here take a closer look at leaf venation in Tephroseris and other species of Asteraceae–Senecioneae. We found that leaf venation in Tephroseris is distinct from leaf venation in Jacobaea vulgaris and Senecio vulgaris, which both have pinnately veined leaves as typical for most species of their respective genera, and that description of the leaves of Tephroseris as pinnately veined is i…
World-wide variation in Drosophila melanogaster sex pheromone: behavioural effects, genetic bases and potential evolutionary consequences
1996
0016-6707 (Print) Journal Article Research Support, Non-U.S. Gov't; In Drosophila melanogaster, male wing vibration, a key element of courtship behaviour, is most efficiently induced by a female-specific contact pheromone cis, cis 7,11 heptacosadiene (7,11 HD), which is the main mature female cuticular hydrocarbon in the CS laboratory strain. A study of 63 strains from around the world revealed that flies from Sub-Saharan Africa and the Caribbean are unique in showing low levels 7,11 HD and high levels of the position isomer 5,9 HD. This difference maps to chromosome III, perhaps indicating a simple genetic control of the 7,11 HD:5,9 HD ratio. Females from strains with high levels of 7,11 H…
Reproductive site selection: evidence of an oviposition cue in a highly adaptive dipteran, Drosophila suzukii (Diptera: Drosophilidae)
2020
Abstract Drosophila suzukii (Matsumura) is a vinegar fly species that originates from Eastern Asia and has spread throughout Europe and the Americas since its initial detection in United States in 2008. Its relatively large, sclerotized, and serrated ovipositor enables the ability to penetrate ripening fruits, providing a protected environment for its egg and larval stages. Because the mechanism of oviposition site selection of D. suzukii is a matter of hypothesis, the aim of the present study was to elucidate behavioral and chemical aspects of short-range ovipositional site selection within the context of D. suzukii reproductive biology. The preference of D. suzukii to lay eggs on artifici…
No inbreeding depression in sperm storage ability or offspring viability in Drosophila melanogaster females.
2013
Mating between relatives usually decreases genetic quality of progeny as deleterious recessive alleles are expressed in inbred individuals. Inbreeding degrades sperm traits but its effects on sperm storage and fate within females are currently unknown. We quantified the relationship between the degrees of inbreeding relevant to natural populations (f=0, 0.25 and 0.50) and the number of sperm inseminated and stored, sperm swimming speed, long-term sperm viability while in storage, pattern of sperm precedence, mating latency, and offspring viability of female Drosophila melanogaster. The use of transgenic flies that have either red or green fluorescent sperm heads allowed us to distinguish tw…
Drosophila cuticular hydrocarbons revisited : Mating status alters cuticular profiles
2010
Editor: Frederic Marion-Poll, INRA - Paris 6 - AgroParisTech, France.; International audience; Most living organisms use pheromones for inter-individual communication. In Drosophila melanogaster flies, several pheromones perceived either by contact/at a short distance (cuticular hydrocarbons, CHs), or at a longer distance (cis-vaccenyl acetate, cVA), affect courtship and mating behaviours. However, it has not previously been possible to precisely identify all potential pheromonal compounds and simultaneously monitor their variation on a time scale. To overcome this limitation, we combined Solid Phase Micro-Extraction with gas-chromatography coupled with mass-spectrometry. This allowed us (i…
Genomic Analysis of European Drosophila melanogaster Populations Reveals Longitudinal Structure, Continent-Wide Selection, and Previously Unknown DNA…
2020
Genetic variation is the fuel of evolution, with standing genetic variation especially important for short-term evolution and local adaptation. To date, studies of spatiotemporal patterns of genetic variation in natural populations have been challenging, as comprehensive sampling is logistically difficult, and sequencing of entire populations costly. Here, we address these issues using a collaborative approach, sequencing 48 pooled population samples from 32 locations, and perform the first continent-wide genomic analysis of genetic variation in European Drosophila melanogaster. Our analyses uncover longitudinal population structure, provide evidence for continent-wide selective sweeps, ide…
First record of Percnon gibbesi (H. Milne Edwards, 1853) (Crustacea: Decapoda: Percnidae) from Egyptian waters
2011
3 pages, 2 figures
Threatened biogenic formations of the Mediterranean: Current status and assessment of the vermetid reefs along the Lebanese coastline (Levant basin)
2019
Abstract Vermetid reefs are a key intertidal habitat in the warm-temperate part of the Mediterranean Sea and in some subtropical and tropical regions in the Atlantic and Pacific oceans. This unique and highly diverse ecosystems is under siege due to both the high anthropogenic pressure and the global climate change, with documented local population declines in the Eastern Mediterranean. This study aims at evaluating the conservation state of vermetid reefs along the Lebanese coast (Eastern Mediterranean), where seawater warming, habitat degradation and coastal urbanization likely threaten their presence. In order to assess the conservation status of vermetid reefs in Lebanon, five sites wer…
Cellular encapsulation in the eastern subterranean termite, Reticulitermes flavipes (Isoptera), against infection by the entomopathogenic fungus Meta…
2009
Reticulitermes flavipes workers were topically inoculated with approximately 10,000 conidia of the entomopathogenic fungus Metarhizium anisopliae. After being kept in groups of 20 individuals for 1-9 d, histopathological examination showed that termites had an individual immune reaction. The nodule formation at the point of entrance of the fungal hyphae was identified as a cellular encapsulation and the different steps in the nodule formation are described. The relative number of hemocytes per termite increased 24h after fungal exposure and remained high in the hemolymph for at least 3 d before decreasing back to pre-exposure levels. The role of an individual immune cellular reaction in soc…