Search results for " Systematics."
showing 10 items of 4820 documents
The comparison of beta-thymosin homologues among metazoa supports an arthropod-nematode clade.
2000
The definition of an Ecdysozoa clade among the protostomians, including all phyla with a regularly molted alpha-chitin-rich cuticle, has been one of the most provocative hypotheses to arise from recent investigations on animal phylogeny. Here we present evidence in favor of an arthropod-nematode clade, from the comparison of beta-thymosin homologues among the Metazoa. Arthropods and nematodes share the absence of the highly conserved beta-thymosin form found in all other documented bilaterian phyla as well as sponges, and the possession of a very unusual, internally triplicated homologue of the beta-thymosin protein, unknown in other phyla. We argue that such discrete molecular character is…
Composition and Trophic Structure of Detrital Food Web in Ant Nest Mounds of Formica aquilonia and in the Surrounding Forest Soil
1998
Community composition and food web structure of soil decomposer biota in relation to various habitat properties were compared between upper parts of red wood ant (Formica aquilonia) nest mounds and the adjacent forest soil. For a description of trophic structure of the decomposer community in the two habitats, soil decomposers were classified into 14 trophic groups. Classification of the taxa into three habitat preference categories resulted in a clear division of the fauna into either soil or nest specialists, relatively few taxa falling between these two groups. A large majority of the nest specialists belonged to a non-myrmecophilous soil decomposer fauna so far largely overlooked in stu…
Thresholds in selection of breeding habitat by the Eurasian treecreeper (Certhia familiaris)
2005
Abstract Assessment of habitat thresholds is a topical issue in ecology, both from theoretical and applied perspectives. We examined how forest structure influences selection of breeding habitat in the Eurasian treecreeper (Certhia familiaris). It is an old-growth forest passerine, which can be considered an umbrella species. Habitat selection data, covering five breeding seasons, were collected from a study area across three spatial scales: (a) territory core scale (a radius of 30 m), (b) territory scale (a radius of 200 m) and (c) large scale (a radius of 500 m). Logistic regression analyses revealed that the radii of 30 and 200 m from the nest were the most important spatial scales for t…
Effects of harvesting timber stands on goshawk nesting in two European areas
2001
We evaluated the effects of harvesting timber stands on goshawk (Accipiter gentilis) nesting in two European areas (central Italy and eastern France), by studying their occupancy and reproductive performance. We found no difference in the productivity of goshawk pairs reproducing in unlogged vs. logged stands. When considering the same nesting stand, before and after timber harvesting, we noted no differences in the number of young per breeding pair nora year effect. We observed that 87.5% of goshawk pairs nesting in logged stands moved away only when the original stand structure was altered by > 30%, and then only to the nearest neighbouring mature stand (maximum distance ca. 1.5 km). The …
Zur Bedeutung des Geruchssinnes beim Nahrungserwerb von Kröten (Amphibia, Anura, Bufonidae): Versuche mit der Kreuzkröte (Bufo calamita Laur.)
1975
The influence of olfactory and visual prey stimuli on the feeding behaviour of toads was studied as well as their response to lasting olfactory cues. A further aim was to find simple methods for testing olfactory responsiveness in anurans. Subjects were 8 adult specimens of the European species Bufo calamita (natterjack) kept in captivity one year at least. The results point to the role of olfaction in these animals.
Pseudorhynchus raggeanus nomen novum
2021
Massa, Bruno (2021): Pseudorhynchus raggeanus nomen novum. Zootaxa 4991 (3): 592-592, DOI: https://doi.org/10.11646/zootaxa.4991.3.9
Dorsthippus and Aethiopiacris: synonymic genera of Dwarf Grasshoppers of the Ethiopian highlands (Orthoptera: Acrididae)
2020
The grasshopper species of the genera Dorsthippus Donskoff, 1977 (D. baleensis) and Aethiopiacris La Greca, 1994 (A. parva) of the Ethiopian highlands are very poorly known. Little information is a...
Erratum: on the correct name of Scolocerca thomasi Massa, 2021 (Orthoptera, Tettigoniidae, Phaneropterinae) from Côte d’Ivoire
2021
Massa, Bruno (2021): Erratum: on the correct name of Scolocerca thomasi Massa, 2021 (Orthoptera Tettigoniidae, Phaneropterinae) from Côte d'Ivoire. Zootaxa 4963 (2): 400-400, DOI: https://doi.org/10.11646/zootaxa.4963.2.11
Upper Givetian and Frasnian (Middle and Upper Devonian) conodonts from Ampriú (Aragonian Pyrenees, Spain): global correlations and palaeogeographic r…
2012
This report describes for the first time a part of the Middle and Upper Devonian conodont sequence of the Sierra Negra Subfacies in the Aragonian Pyrenees (Spain), establishing the basis for further sound correlations both across the distinct Pyrenean facies and subfacies and on other relevant world areas. The description of 20 conodont taxa and their stratigraphical distribution permits recognition of two separate time intervals. The older one corresponds to the lower Upper Givetian (Middle Devonian), hermanni to crista- tus ectypus zones. The younger interval is uppermost Lower Frasnian to lower Middle Frasnian (Upper Devonian) and is equivalent to MN4-MN6 zones. The combination of litho-…
Coralline algal growth-increment widths archive North Atlantic climate variability
2011
Over the past decade coralline algae have increasingly been used as archives of paleoclimate information. Encrusting coralline algae, which deposit annual growth increments in a high Mg-calcite skeleton, are amongst the longest-lived shallow marine organisms. In fact, a live-collected plant has recently been shown to have lived for at least 850 years based on radiometric dating. While a number of investigations have successfully used geochemical information of coralline algal skeletons to reconstruct sea surface temperatures, less attention has been paid to employ growth increment widths as a temperature proxy. Here we explore the relationship between growth and environmental parameters in …