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Vegetationsdynamik verlandeter Biberteiche auf der Insel Navarino (Feuerland-Archipel, Chile)
(2009)
Die vorliegende Fallstudie veranschaulicht die Auswirkungen des invasiven Nordamerikanischen Bibers (Castor canadensis) auf den autochthonen Nothofagus-Wald der ca. 2500 km2 großen Insel Navarino im Feuerland-Archipel (Archipiélago de Tierra del Fuego), Chile. Dazu wurden auf den Sukzessionsflächen verlandeter Biberteiche (1) Diversität (absolute Artenzahl, mittlere Artenzahl, Artendichte, Shannon-Wert und Evenness), (2) Artenzusammensetzung, (3) Anteil gebietsfremder Pflanzenarten. (4) Baumartenzusammensetzung, (5) Dichte, (6) Stammdurchmesser und (7) die Wuchshöhe der Gehölzverjüngung untersucht. Die Ergebnisse zeigen auf den Sukzessionsflächen eine deutliche Zunahme der Diversität mit Ausnahme der mittleren Artenzahl. Die ehemaligen Biberteiche zeichnen sich durch eine charakteristische Artenzusammensetzung aus, die insbesondere durch Weide- und Überschwemmungszeiger bestimmt wird und sich erheblich von biberfreien Waldflächen unterscheidet. Der Anteil gebietsfremder Pflanzenarten variiert stark, wofür noch keine Determinanten festgestellt werden konnten. Im Unterschied zu von Bibern unbeeinflussten Nothofagus-Wäldern wird die Verjüngung auf den Sukzessionflächen von Nothofagus antarctica dominiert. Es wurden folgende fünf Faktoren identifiziert, die als wesentliche Steuergrößen für die Etablierung von Nothofagus in Betracht gezogen werden können: (1) relative Lage des Spenderbiotops, (2) Vorkommen von Totholz, (3) Beweidung, (4) Konkurrenz und (5) Überschwemmung.
Two species of the genus Ophelina Örsted, 1843 (Annelida, Opheliidae) are reported from the coast of Kuwait (Arabian Gulf) after specimens collected in the intertidal and shallow subtidal, namely Ophelina arabica sp. nov. and Ophelina grandis (Pillai, 1961). The new species is mainly characterised by features of the anal tube, which is provided with about 25 annulations at each side; the ventral margins are fully fused while dorsal margins are fused at most of their length but are free at the distal end in the shape of a conspicuous incision; the posterior end is opened with free margins; the anal tube also lacks marginal papillae but bears a pair of basal papillae and an unpaired anal cirrus attached to ventral margin at mid-length. Ophelina grandis is reported for the first time in the Arabian Gulf; specimens are fully described and compared with similar species. A key for species of Ophelina in the Indo-Pacific, Southern Asia, Indo-Malay Archipelago and Australia, is also provided.
Based on samples collected during the BIOICE project off Iceland, four species of marine annelids belonging to the family Pectinariidae were identified: Amphictene auricoma (O.F. Müller, 1776), Cistenides granulata (Linnaeus, 1767), Cistenides hyperborea Malmgren, 1865 and Lagis koreni Malmgren, 1866. Taxonomic remarks and data on geographical and bathymetric distribution are presented. The distribution of each species off Iceland was evaluated and two patterns were defined: C. granulata and C. hyperborea were mainly found in waters off the northeast coast, while A. auricoma and L. koreni were found on the southern coast. Several body characters with taxonomic value in this family were reviewed under the stereo microscope and scanning electron microscope, with special emphasis on the neuropodial uncini. Remarks on these special chaetae are included in the diagnoses.
Two new species of subgenus Heterophyllidiae subsection Cyanoxanthinae, Russula fusiformata Y.Song sp. nov. and R. purpureorosea Y.Song sp. nov., collected from the Dinghushan Biosphere Reserve (DHSBR), are described based on both morphology and a phylogenetic analysis of the internal transcribed spacer (ITS), further increasing Heterophyllidiae species diversity in the area. Differences between the two new species and related taxa are analyzed. The other 17 reported species of Russula subgenus Heterophyllidiae that have been collected from DHSBR during mushroom explorations since 2014 are also summarized. The dominant species and the ecological distribution of all 19 species are briefly discussed, and most species are presented in macrofungal plates.
The current knowledge of the scorpionfly genus Dicerapanorpa Zhong & Hua, 2013 is taxonomically reviewed. Two new species of Dicerapanorpa are described and illustrated, increasing the species number of this genus to 20. Dicerapanorpa bifurcata sp. nov. from the Minshan Mountains, Sichuan Province, is characterized by the absence of the paramere basal branch and the elongated mesal branch in males, and the medigynium having a short basal stalk in females. Dicerapanorpa zhengkuni sp. nov. from the Wuling and Miaoling Mountains, Guizhou Province, is distinguishable by the greatly elongated hypovalves, the very short basal branch of the paramere, and the dorsomedially curved lateral branch in males, and the rounded main plate of the medigynium in females. An updated key to species of Dicerapanorpa is presented.
Patterns and processes of cladogenesis among taxa living on the Mozambique ‘sky islands’ remain poorly studied. During the present study, we report on a new freshwater crab species from Mount Lico, an inselberg and ‘sky island’ in the Zambezia Province of Mozambique. Phylogenetic analyses using three mitochondrial DNA sequence loci (12S rRNA, 16S rRNA and COI) were used to determine the evolutionary placement of the freshwater crab specimens from Mount Lico. The freshwater crab specimens from Mount Lico were retrieved sister to Potamonautes choloensis. The new species, Potamonautes licoensis sp. nov., is described and compared with other southern African freshwater crab species. Divergence time estimations for the Mozambican freshwater crab species suggest a Miocene / Plio–Pleistocene diversifi cation. Some endemic ‘sky island’ species form an early branching and are sister to other predominantly East African species, while other ‘sky island’ species are more recently derived and nested within a predominantly southern African clade. The present study presents the description of the fourth endemic freshwater crab species from Mozambique and suggests that the species diversity in the country is likely highly underrepresented, reiterating the call for renewed systematic surveys. An argument for the conservation of these mountainous ‘sky islands’ is presented.
Another survey of Odonata on the Indonesian island of Belitung is reported. This survey was the second survey conducted in the Belitung area with International Dragonfly Fund support and was focused to Belitung Regency's outer islands. Seventy two species were recorded during the survey. Significant records from the surveyed islands include Amphicnemis kuiperi, Mortonagrion arthuri, Mortonagrion appendiculatum, Teinobasis ruficollis, Platylestes heterostylus, Pornothemis serrata, Pornothemis starrei and Tramea phaeoneura. Almost all the records are new to the small islands surveyed, except for Mendanau Island for which there were already records of four species. A checklist of the odonate fauna of the outer islands is given in an appendix.
The current forest policy in Germany is to change forest monocultures into mixed forests. This is based on the assumption that monocultures are less robust against climatic influences (e.g. storm, drought), more susceptible to pest organisms (JACTEL et al. 2002, WOODS 2003, BURTON et al. 1992) and are for several insect taxa known to show a lower species richness in comparison to mixed forests (YOUNG 1986, BARKMAN 1992, BURKHART & THAM 1992, DENNIS 1997, BRAGANCA et al. 1998). This investigation wanted to verify this thesis in forests consisting of European beech (Fagus sylvatica), Norway spruce (Picea abies) and of both tree species. The area of investigation was in the Solling region, a large woodland in Lower Saxony (Germany).
This paper contains the results of research on a large assemblage of jumping spiders collected by J.-C. Ledoux from Ivory Coast in 1974–75. In total, 105 species are included. Three new genera are erected Pulcherula gen. nov., Sphericula gen. nov. and Vicirionessa gen. nov. Two generic names are synonymized, Polemus Simon, 1902 with Baryphas Simon, 1902 and Brancus Simon, 1902 with Thyene Simon, 1885. Twenty eight new species are described: Afraflacilla albopunctata sp. nov. (♀), Ansienulina lamottei sp. nov. (♂), Asemonaea pusilla sp. nov. (♀), Detalik cavally sp. nov. (♀), Evarcha zougoussi sp. nov. (♀), Heliophanus (Heliophanus) minimus sp. nov. (♂♀), Hyllus ignotus sp. nov. (♀), Hyllus solus sp. nov. (♀), Hyllus unicolor sp. nov. (♀), Icius bandama sp. nov. (♂♀), Langona recta sp. nov. (♂), Malizna zabkai sp. nov. (♀), Menemerus niangbo sp. nov. (♀), Myrmarachne galea sp. nov. (♀), Phintella brevis sp. nov. (♂), Phintella globosa sp. nov. (♀), Phintella occidentalis sp. nov. (♂), Phintella transversa sp. nov. (♂), Pochytoides mirabilis sp. nov. (♂♀), Pochytoides tonkoui sp. nov. (♀), Pochytoides tournieri sp. nov. (♂), Pulcherula magna gen. et sp. nov. (♂), Rhene ferkensis sp. nov. (♀), Sonoita ledouxi sp. nov. (♂♀), Sphericula globulifera gen. et sp. nov. (♀), Thiratoscirtus silvestris sp. nov. (♂♀), Tusitala bandama sp. nov. (♀) and Tusitala cornuta sp. nov. (♂). Five specific names are synonymized: Polemus chrysochirus Simon, 1902 with Baryphas jullieni Simon, 1902, Viciria mondoni Berland & Millot, 1941with Malloneta guineensis Simon, 1902, Brancus lacrimosus Wesołowska & Edwards 2008 with Vicirionessa fuscimana (Simon, 1903), Viciria monodi Berland & Millot, 1941 and Viciria equestris pallida Berland & Millot, 1941 with Vicirionessa equestris (Simon, 1903). Hyllus natali peckhamorum Berland & Millot, 1941 is removed from synonymy of Hyllus brevitarsis Simon, 1902, revalidated and its rank is raised as Hyllus peckhamorum Berland & Millot, 1941 stat. nov. Also rank of Telamonia aequipes minor Lessert, 1925 is elevated as Phintella minor (Lessert, 1925) stat. nov. Menemerus dubius Berland & Millot, 1941 is removed from nomina dubia. This species is considered valid and is redescribed. A lectotype is designated for it. The male of Mexcala torquata Wesołowska, 2009 and females of Hyllus tuberculatus Wanless & Clark, 1975, Iranattus principalis (Wesołowska, 2000), Myrmarachne eidmanni Roewer, 1942 and Thiratoscirtus tentativus (Szűts & Jocqué, 2001) are described for the first time. Many new combinations are proposed. Twenty ex Brancus are recombined: Hyllus nigeriensis (Wesołowska & Edwards, 2012) comb. nov., Thyene blaisei (Simon, 1902) comb. nov., Thyene calebi (Kanesharatnam & Benjamin, 2018) comb. nov., Thyene mutica (Simon, 1902) comb. nov., Thyene verdieri (Berland & Millot, 1941) comb. nov., Vicirionessa besanconi (Berland & Millot, 1941) gen. et comb. nov., Vicirionessa fuscimana (Simon, 1903) gen. et comb. nov., Vicirionessa mustela (Simon, 1902) gen. et comb. nov., Vicirionessa niveimana (Simon, 1902) gen. et comb. nov., Vicirionessa occidentalis (Wesołowska & Russell-Smith, 2011) gen. et comb. nov., Vicirionessa peckhamorum (Lessert, 1927) gen. et comb. nov., Vicirionessa signata (Dawidowicz & Wesołowska, 2016) gen. et comb. nov. Four ex Viciria are recombined: Vicirionessa chabanaudi (Fage, 1923) gen. et comb. nov., Vicirionessa equestris (Simon, 1903) gen. et comb. nov., Vicirionessa prenanti (Berland & Millot, 1941) gen. et comb. nov., Vicirionessa tergina (Simon, 1903) gen. et comb. nov. and one species ex Hyllus: Vicirionessa albocincta (Thorell, 1899) gen. et comb. nov. Furthermore, the following two new combinations are proposed: Thiratoscirtus tentativus (Szűts & Jocqué, 2001) comb. nov. (ex Bacelarella) and Baryphas galeatus (Simon, 1902) comb. nov. (ex Polemus). For 11 species known so far from single records new data are presented: Heliophanus butemboensis Wesołowska, 1986, Hyllus lwoffi Berland & Millot, 1941, Hyllus tuberculatus Wanless & Clark, 1975, Menemerus dubius Berland & Millot, 1941, Mexcala torquata Wesołowska, 2009, Neaetha maxima Wesołowska & Russell-Smith, 2011, Pachyballus miniscutulus Wesołowska, Azarkina & Wiśniewski 2020, Phintella paludosa Wesołowska & Edwards, 2012, Thiratoscirtus gambari Wesołowska & Russell-Smith, 2011, Tusitala guineensis Berland & Millot, 1941 and Tusitala lutzi Lessert, 1927.
The intensification of agricultural practices has led to a severe decrease in grassland biodiversity. Although there is strong evidence that organic farming can reduce the negative impacts of land use, knowledge regarding the most beneficial management system for species richness on organic grasslands is still scarce. This study examines differences in the biodiversity of plants and butterflies on rotationally and continuously grazed pastures as well as on meadows cut twice per year on two large organic suckler cow farms in NE Germany. Vegetation and flower abundance, as factors likely to influence butterfly abundance and diversity, were compared and used to explain the differences. The data attained by vegetation assessments and monthly transect inspections from May to August were analyzed using descriptive statistics and nonparametric methods. The abiotic site conditions of the studied plots had more influence on plant species numbers than the management method. Dry and nutrient-poor areas (mainly poor types of Cynosurion) and undrained wet fens (Calthion) were important for phytodiversity, measured by the absolute number of species, indicator species for ecologically valuable grasslands and the Shannon Index. Meadows tended to have more indicator species than pastures, where small-scale special sites such as wet depressions were crucial for plant diversity. Butterfly diversity was very low, and 90% of the recorded butterflies were individuals of the generalist species Pieris napi. Butterfly abundance depended mainly on occurrence of specific habitat types and specific larval host plants. Supply of flowers was crucial only in certain time periods. Differences in butterfly abundance between the management systems could be explained by the site conditions of the studied grasslands. We conclude that meadows are more favorable to support ecologically valuable plant species; however, their extension is contradictory to the organic farming method of suckler cows maintained outside of stables. Rotationally grazed pastures could be a compromise that would enhance the temporal heterogeneity of flower abundance and vegetation structure. The plant diversity on pastures should be improved by less intensive grazing on special sites and plant species enrichment by means of hay transfer. For enhancing butterfly diversity we suggest to reduce land use intensity especially on poor soils. Considering the economic perspective of the farms, small parts of the agricultural area could be sufficient if connectivity to other suitable habitats is assured. Flower abundance and diversity of larval host plants could be promoted by high diversity of farming practices as well as pre-serving small uncut strips of meadows.