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showing 10 items of 18693 documents
Otolith-based age and growth of the Lessepsian species Fistularia commersonii (Osteichtyes: Fistulariidae) in South of Sicily (Central Mediterranean …
2016
During spring–summer 2013, 23 specimens of the Lessepsian Fistularia commersonii Rüppell, 1838 were studied through occasional catches by artisanal and coastal trawler fisheries in the South of Sicily (Mediterranean Sea). The total lengths (TL, cm, without filament) and weight (W, g) ranged between 69.0 and 104.0 cm and 155 and 798 g, respectively. The estimated sex-combined parameters of the length–weight relationship (k = 9*10–9; b = 3.6) suggested a positive allometry. All pairs of sagittae were examined under a stereomicroscope and the age estimated by counting the complete translucent zones, both as whole and thin sections, with ages from 3 to 5 years. Growth parameters (von Bertalanff…
Das phylogenetische System
2003
Arten konnen im Lauf der Zeit als Linien aufgefast werden, die durch Aufspaltungsereignisse gegeneinander abgegrenzt sind. Anhand der Abfolge solcher Aufspaltungen lassen sich Arten in einem hierarchischen System, dem phylogenetischen System, zusammenfassen. Nachfolgend werden wir uns zunachst mit dieser Hierarchie der Arten und ihren Einheiten befassen. Dann werden wir uns naher mit dem Gedanken zur Artbildung durch Hybridisierung auseinandersetzen, weil er die konsequ ent hierarchische Struktur des phylogenetischen Systems in Frage stellt.
Urania sloanus (Cramer, 1779) (Lepidoptera: Uraniidae), an Enigmatic Extinct Species in Polish Museum Collections
2019
Urania sloanus is an endemic species in Jamaica. The species probably became extinct at the end of the 19th century or the beginning of the 20th century. During the work on combining the collections of exotic butterflies in the Upper Silesian Museum in Bytom, one specimen of this taxon was found. The discovery of this species in the Museum of Upper Silesia in Bytom led us to search for entomological collections in other Polish museums. As a result of our search, we found three additional specimens: two specimens in the collection of the Museum of Natural History of the University of Wrocław and one at the Zoological Museum of the Polish Academy of Sciences in Warsaw. In total, in the Polish…
A revision of the new world species of Gymnoclasiopa Hendel (Diptera, Ephydridae)
2012
Species of the shore-fly genus Gymnoclasiopa Hendel from the New World are revised, including G. grecorum, sp. n. (Alaska. Juneau: Gastineau Channel, Thane Road (S Juneau; 58°16.9’N, 134°22.4’W)) and G. matanuska, sp. n. (Alaska. Matanuska-Susitna: Palmer (Matanuska River; 61°36.5’N, 149°04.1’W)). We also clarify the status of previously described species, including those now discovered to have Holarctic distributions and/or for which sexual dimorphism was not appreciated and the species was described twice, including G. montana (Cresson) as a syn. n. of G. bohemanni (Becker). Two species, G. bella (Mathis), comb. n., and G. chiapas (Mathis), comb. n., are transferred from Ditrichophora to …
Systematic Position of Gastropini (Diptera: Ephydridae), and a Review of Two Included Genera:GastropsWilliston andNotacanthinaMacquart
2017
The placement of the tribe Gastropini within the subfamily Gymnomyzinae, with the tribe Gymnomyzini as a sister-group, is supported. Validity for two genera Gastrops Williston and Notacanthina Macquart (senior synonym of Beckeriella Williston) is maintained. Particular characters of their proboscis, ventral receptacle and the male terminalia are presented. A key to species and habitus photographs of selected species of Gastrops and Notacanthina are provided. The following new combinations are proposed: Notacanthina clypeata (Lizarralde de Grosso, 1986), comb. nov., N. fasciata (Mathis & Grimaldi, 2000), comb. nov., N. filipina (Lizarralde de Grosso, 1994), comb. nov., N. gigas (Lizarralde d…
A century after introduction: variability in Cepaea hortensis (Müller, 1774) in Sibiu, central Romania
2019
AbstractThe polymorphic land snail Cepaea hortensis was introduced to the city of Sibiu, central Romania, in the first decade of the 20th century and has spread widely across the city. A total of 97 locations were examined in 2017 across the city to determine the habitat preferences and variation in shell size, shape, colour and banding polymorphism of C. hortensis, and to relate these to the same features in the likely source population from Mannheim, Germany, and the first established population in Sibiu. We found that C. hortensis was largely restricted to sites with some woody vegetation cover and showed a marked preference for abandoned and overgrown private gardens. Mean adult shell s…
Novel sexual dimorphism in a new genus of Bathynellidae from Russia, with a revision of phylogenetic relationships
2019
Bathynellidae is the neglected family of Bathynellacea, a groundwater group of crus- taceans with 33 genera and 107 species described and almost half of them included in the `catch-all¿ genus Bathynella. Due to the morphological homogeneity of the spe- cies, the taxonomic uncertainties have accumulated over time. Therefore, to explore the phylogenetic relationships among taxa, a combined approach using morphologi- cal and molecular data is needed. In this paper, we performed a phylogenetic analysis based on partial sequences of COI and 18S including 30 species of Bathynellidae. This data set represents the most updated one, including a new genus and a new spe- cies (Altainella calcarata gen…
Allelopathy and the role of allelochemicals in plant defence
2017
International audience; Allelopathy is described as the interference to plant growth resulting from chemical interactions among plants and other organisms mediated through release of plant-produced bioactive secondary metabolites referred to as allelochemicals. A number of mechanisms have been studied for the release of allelochemicals from various plant tissues including volatilization or leaching from aerial parts, exudation from roots and decomposition of plant residues in soil. Despite differences in biological activity and mode of action, related compounds commonly share similar biosynthetic pathways while some classes of metabolites can be produced using diverse biosynthetic pathways.…
Ant recognition cue diversity is higher in the presence of slavemaker ants
2015
Social insect colonies defend themselves from intruders through nestmate recognition, yet the evolution and maintenance of recognition cue diversity is still poorly understood. We compared the recognition cue diversity of 9 populations of Temnothorax longispinosus ant colonies, including populations that harbored the socially parasitic slavemaker ant, Protomognathus americanus. Although ants recognize friends from foe based on recognition cues encoded in their cuticular hydrocarbon profile, which specific compounds are involved in recognition is unknown for most species. We therefore started by statistically identifying 9 putative recognition compounds involved in worker and colony aggressi…
Cuticular hydrocarbon profiles differ between ant body parts: implications for communication and our understanding of CHC diffusion.
2020
Abstract Insect cuticular hydrocarbons (CHCs) serve as communication signals and protect against desiccation. They form complex blends of up to 150 different compounds. Due to differences in molecular packing, CHC classes differ in melting point. Communication is especially important in social insects like ants, which use CHCs to communicate within the colony and to recognize nestmates. Nestmate recognition models often assume a homogenous colony odor, where CHCs are collected, mixed, and redistributed in the postpharyngeal gland (PPG). Via diffusion, recognition cues should evenly spread over the body surface. Hence, CHC composition should be similar across body parts and in the PPG. To te…