Review of Colombian Conchostraca (Crustacea) — ecological aspects and life cycles — family Cyclestheriidae

This study gives an overview and describes special aspects of the biology, ecology and the life cycle ofCyclestheria hislopi (Baird, 1859). This species is most commonly found in parthenogenically reproducing populations which produce large, directly developing nondiapause eggs. But periodically and under certain environmental conditions, sexually reproducing generations appear and produce diapause eggs. the sexual generations include males and particularly constituted females, which undergo a complete transformation into a special type of ephippium.Cyclestheria is the only known conchostracan species which does not occur in the initial phases of temporary water bodies, but develops in older temporary pools and even in permanent waters. It survives in the presence of effective depredators like fish by hiding within a special self-made mucus capsule.     

Review of Colombian Conchostraca (Crustacea) — morphotaxonomic aspects

This paper presents an overview of the current knowledge about species diversity and morphological taxonomy of the Colombian conchostracan fauna. Relationships among morphological variability, reproduction biology and environmental conditions are stressed. The Colombian fauna includes 12 species in five families: Limnadiidae Sars, 1896; Leptestheriidae Daday, 1915; Cyclestheriidae G. O. Sars, 1899; Metalimnadiidae Strakraba, 1965; and Lynceidae Stebbing, 1902. No member of the families, Cyzicidae Stebbing, 1910, or Imnadiidae Botnariuc & Orghidan 1941 have been found in Columbia. Morphology depends on developmental stage and on the modulating effects of environmental conditions. Extremely high temperatures may lead to specimens with neotenic features inEulimnadia magdalenensis Roessler, 1990.     

Adventive flora of Israel — Phytogeographical,ecological and agricultural aspects

73 adventive wild species occur in the flora of Israel: 39 are of tropical origin, 20 are North American. The geographical distribution pattern suggests that about two thirds of the species reached Israel through neighbouring countries, while only one third arrived directly from their countries of origin. — Three patterns of population dynamics can be recognized: accidental species (7), colonizing species (30), and species penetrating into natural habitats (3). There is insufficient information about the remaining species. — About 20 species are widespread noxious weeds which now have economic significance in Israel, 20 others are known to have similar ecological tendencies in other countries. These species soon may become aggressive weeds in Israel.     

Tolerance, optimum ranges, and ecological requirements of freshwater Ostracoda (Crustacea) in Lake Aladağ (Bolu, Turkey)

During monthly sampling from Lake Alada (Bolu, Turkey) between April 2003 and June 2004, nine ostracod taxa (Candona candida, Cypridopsis vidua, Darwinula stevensoni, Eucypris virens, Eucypris sp., Heterocypris sp., Limnocythere inopinata, Physocypria kraepelini, and Tonnacypris lutaria) were recorded from seven stations. Physocypria kraepelini was commonly found in the lake while the others were recorded in particular months. UPGMA analyses clustered three groups based on their occurrence. Accordingly, the occurrence of species (C. candida, E. virens, and T. lutaria) was positive and significantly related to each other. Two species, P. kraepelini and D. stevensoni, showed a significant positive relationship with electrical conductivity. A significant negative correlation was found between the occurrence of P. kraepelini and dissolved oxygen, while there was a significant positive correlation between the occurrence of P. kraepelini and turbidity. About 76% of the relationship between species and environmental factors was explained by the first two axes of canonical correspondence analyses (CCA). Temperature and dissolved oxygen were the two most important influences on the species assemblages. All species showed different but high optima and tolerance ranges, corresponding with their cosmopolitan characteristics. These responses may be related to unstable ecological characteristics of Lake Alada, which is often subjected to human activity.     

Distribution, ecological tolerance and optimum levels of freshwater Ostracoda (Crustacea) from Diyarbak?r, Turkey

A total of 23 ostracod taxa were found in 48 of 90 different water bodies (wetlands, springs, lakes, creeks, etc.) located at moderate to high elevation (530–1,095 m) in Diyarbakır province. The ecological tolerances and optimum values for environmental variables of 15 species were analyzed. Accordingly, maximum numbers of species were found between 700 and 800 m. Ostracod species and sampling sites along with seven environmental variables were ordinated with canonical correspondence analysis (CCA). The first axis of CCA explained 72% of the relationship between species and environmental variables. Of these, water temperature, redox potential and altitude were the most influential (P < 0.05) factors for species. Based on habitat similarities, an unweighted pair group mean average dendrogram divided species into four clustering groups. Among the species, Potamocypris arcuata, Candona neglecta and Psychrodromus fontinalis had the highest optimum estimates for altitude, whereas P. arcuata, Herpetocypris brevicaudata and P. fontinalis exhibited the highest tolerances to altitude. While most species revealed unique tolerances and optimum values for different ecological variables, species with cosmopolitan characteristics had wider ranges of ecological tolerances and distribution amid the variety of habitats along elevational gradients.     

Distributions,life cycles and hybridization of two Mysis relicta group species (Crustacea: Mysida) in the northern Baltic Sea and Lake Båven

We used electrophoretically identified material to assess the geographical distributions, life cycles and interspecific hybridization of two sibling species of the Mysis relicta species group (sp. I and sp. II) in the northern Baltic region. In the Gulf of Finland, sp. I prevails in inshore waters and sp. II in the open sea; the distributions overlap in the outer archipelago zone. In the Gulf of Bothnia, only sp. II was found in the southern part (Bothnian Sea), whereas the two species coexist throughout the northerly Bothnian Bay. Both the local and large-scale distributions are salinity-related, but salinity alone does not explain the differences. The two species exhibit different patterns of geographical variation in their life histories. In strict sympatry in the north they have identical two-year life cycles with winter breeding. Further south (Gulf of Finland), sp. I exhibits a predominantly one-year winter-breeding cycle, whereas sp. II breeds throughout the year. The patterns comply with the concept of a great phenotypic flexibility and environmental control of life history characteristics in the Mysis relicta group, and make a contrast to the stable life cycle of the congeneric M. mixta. F1 hybrids between the two M. relicta group species were found at a low frequency (0.6%) in the Bothnian Bay, but not in other areas of sympatry. This revised version was published online in July 2006 with corrections to the Cover Date.     

Age-influenced morphological changes inLeptestheria saetosa Marinček et Petrov, 1992 (Conchostraca,Crustacea)

Morphological changes during the process of ageing ofLeptestheria saetosa Marinek et Petrov, 1992 were observed. It was established thet the greatest number of analysed characteristics change intensively after sexual maturation. These changes continue throughout the entire life, although they are very slow in old specimens. Such a large number of changes brings about considerable morphological differences between adult specimens of different age.     

Die Rezeptoren an den ersten Antennen vonLeptestheria dahalacensis Rüppel (Crustacea,Conchostraca)

Zusammenfassung Bei dem ConchostracenLeptestheria dahalacensis kommen auf den ersten Antennen etwa 600 gleich aussehende Sinneshaare vor, die in Gruppen von jeweils 25–30 zusammengefaßt sind. Diese Sinneshaare sind in zwei Teile gegliedert, die durch das lichtmikroskopisch gut sichtbare Basalstück (basal bead) voneinander getrennt sind. Dieses bildet die Basis des Haares, dessen Wand im wesentlichen aus Epicuticula besteht. Apikal wird das Haar durch das Endkügelchen (terminal pellet) abgeschlossen. Das Basalstück wird von der untersten Lage der Epicuticula gebildet. Die 4–10 Receptorcilien, die jeweils einzeln ebensovielen Dendriten aufsitzen, ziehen aus dem inneren Teil des Rezeptors, der von insgesamt 5 Hüllzellen umgeben wird, durch das Basalstück, in dem sie stark eingeengt werden und verzweigen sich dann im äußeren Teil des Rezeptors. Sie ziehen bis zum Endkügelchen, in das sie durch einen Porus, den man als Häutungsporus ansprechen kann, eintreten. In der Häutungsvorbereitung wird der Haarbalg von der Hüllzelle 5, das Basalstück von der Hüllzelle 4, der Haarschaft dagegen von der Hüllzelle 3 gebildet. Dabei spaltet sich die Hüllzelle 3 ringspaltförmig auf, so daß in diesem Spalt der neuangelegte Haarschaft handschuhfingerförmig eingestülpt liegt. Die Hüllzelle 2 formt die Spitze des neuen Haares, während die Dendritenscheide von der Hüllzelle 1 abgegeben wird.

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The receptors on the first antennae ofLeptestheria dahalacensis Rüppel (Crustacea, Conchostraca)

Summary On the antennulae ofLeptestheria dahalacensis (Conchostraca) nearly 600 sensory setae of one type are found. They are gathered in groups of 25–30. The single sensory seta is divided into two parts by the basal bead which is easily visible in the light microscope. The basal bead is the socket of the seta, whose wall is mainly built up by the epicuticle. The terminal pellet closes the tip of the seta. The basal bead is derived from the innermost layer of the epicuticle. 4–10 dendrites each with one receptorcilium innervate the receptor. The receptorcilia stretch through the interior part of the receptor and the basal bead into the exterior part, where they branch. They enter the terminal pellet in a porus, which seems to be a moulting porus. The interior part of the receptor is surrounded by 5 sheath cells. During the premoult it becomes obvious, that the socket of the seta is built by the sheath cell 5, the basal bead by the sheath cell 4 and the shaft by the sheath cell 3. For this the sheath cell 3 is divided into two parts. Between this two parts the newly formed cuticle is invaginated. The sheath cell 2 formes the tip and the sheath cell 1 the cuticular sheath of the new bristle.

     

Taxonomic,phylogenetic and ecological diversity of Niphargus (Amphipoda: Crustacea) in the Hölloch cave system (Switzerland)

Groundwater belongs to the spatially most extensive, but least explored freshwater systems. On a global scale, the species richness of several subterranean invertebrate taxa parallels species richness found in surface waters, while on a local scale species richness hardly exceeds 20 species. This results in a high contribution of groundwater ecosystems to regional β- and γ-diversity, and to a smaller degree to α-diversity, and deserves focused attention. In general, more species are to be found in large cave systems. The second largest cave system in Europe is Hölloch in Switzerland. In this paper we revised the taxonomic, phylogenetic and ecological diversity of the amphipod community in the Hölloch cave system. While previous records listed five geographically widespread species of the genus Niphargus for this cave system, we could not confirm the presence of any of those species, but rather found three highly distinct species new to science. In this paper we describe Niphargus styx sp. nov., Niphargus murimali sp. nov., and Niphargus muotae sp. nov., and suggest that previous records from that cave were probably misidentifications. Although amphipod species richness in this cave system seems to be lower than previously thought in terms of absolute numbers, the cave retained its regional and international importance in terms of nature conservation for multiple reasons. First, all newly described species are probably endemic to this cave system. Second, they are phylogenetically distantly related and exhibit moderate to high phylogenetic diversity. Third, the species, as inferred from their functional morphology, are also ecologically highly divergent. Based on geographic distribution of their nearest relatives, we hypothesize that the cave system was most likely independently colonized from North, West and South and that the pre-adapted ancestors occupied different ecological niches within the system.

http://zoobank.org/urn:lsid:zoobank.org:pub:A19309E5-C06B-4844-A4D8-7571F05F25C9     

Leafless autumnal-flowering geophytes in the Mediterranean region — phytogeographical,ecological and evolutionary aspects

Numerous Mediterranean geophytes are hysteranthous, i.e. they flower in a leafless stage during autumn. On the basis of their life cycles and other features two types can be recognized: In the Crocus type flowers with subterranean ovary develop at the start of the new reproductive cycle from an annual storage organ; seed dispersal and germination are delayed to the spring and the next autumn. In the Urginea type, flowers with supraterranean ovary originate from a perennial storage organ at the end of the life cycle; seed dispersal and germination follow flowering immediately. Similar rhythms exist in other seasonal climates. Field observations and some experiments demonstrate flower stimulation by temperature decrease or increase in different geophytes, and relationships between water supply and synanthous versus hysteranthous leaf development. The origin, ecological importance, and horticultural implication of the hysteranthous syndrome is discussed.     

Spinicaudata (“Conchostraca,” Crustacea) from the Middle Keuper (Upper Triassic) of the southern Germanic Basin,with a review of Carnian–Norian taxa and suggested biozones

The Coburg Sandstone member of the Hassberge Formation, Middle Keuper, Carnian, Upper Triassic, in the Germanic Basin of Central Europe contains spinicaudatan branchiopods which considerably broaden the known spectrum and provide important data on the phylogenetic history and intercontinental correlation of this systematic group. The spinicaudatan fauna for this lithostratigraphic unit is described in detail and includes Euestheria kozuri sp. nov., E.? sp. nov. A, Gregoriusella striatula sp. nov., Laxitextella freybergi Kelber and Kozur in Kozur and Weems, 2007, L. dorsorecta (Reible, 1962), and Laxitextella? sp. A. Additional discussions deal with Euestheria multicostata (Geyer, 1987), E. winterpockensis (Bock, 1953a), Laxitextella laxitexta (Sandberger in Jones, 1890), Laxitextella multireticulata (Reible, 1962), and “Laxitextella? hausmanni (Schmidt, 1938),” as well as problems with (sub)global zonations that are based on spinicaudatans and suggested to be of Carnian and Norian age.     

Phospholipids composition and metabolism in the hemolymph of Carcinus maenas (Crustacea,Decapoda)—Effect of temperature

• 1.1. The distribution of different phospholipids and the repartition of fatty acids extracted from hemolymph of crab Carcinus maenas are analysed.
• 2.2. The action of the temperature on the lipid composition is also determined: an increase of content of PE and a slight rise of the degree of unsaturation of fatty acids are found at lower temperatures.
• 3.3. The specific radioactivity of total phospholipids, phosphatidyl-choline and phosphatidylethanolamine from hemolymph of Carcinus maenas is studied from two radioactive precursors (³²Phosphorus and ³H]ethanolamine). Results suggested that the conversion of PE into PC by methylation could take place in hepatopancreas of Carcinus maenas.
• 4.4. The specific radioactivity of phospholipids from these two same radioactive compounds is increased following a variation in the environmental temperature.
• 5.5. The composition of hemolymph lipids could be a direct reflection of the lipid metabolism of the hepatopancreas and that the temperature alters the rate of the phospholipid exchange between hepatopancreas and hemolymph.
• 6.6. It is suggested that these lipid alterations occur in order to permit crab Carcinus maenas to support large changes in environmental temperatures.

     

The post-embryonic development of Remipedia (Crustacea)—additional results and new insights

The post-embryonic development of a species of the enigmatic crustacean group Remipedia is described in detail for the first time under various aspects. Applying a molecular approach, we can clearly prove the species identity of the larvae as belonging to Pleomothra apletocheles. We document the cellular level of several larval stages and the differentiation of segments, limbs, and the general body morphology applying the techniques of confocal laser scanning microscopy and scanning electron microscopy. In addition, we document the swimming behavior and the peculiar movements of the naupliar appendages. A comparison of our results with published data on other Crustacea and their larval development tentatively supports ideas about phylogenetic affinities of the Remipedia to the Malacostraca. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at     

Phytosociological and ecological aspects of the dunes on the Isle of Rügen,Baltic sea

Foredunes, white-, grey- and brown dunes have an important function in coastal protection. Although a close syngenetic connection exists between these neighbouring ecosystems, they are considerably differentiated phytosociologically and ecologically. Whilst on foredunes and white dunes the predominating plant species are characteristic of Ammophiletea, on the grey dunes, species characteristic of the Festuco-Brometea and the Sedo-Scleranthetea are found, and on the brown dunes species of the Nardo-Callunetea.Going through the white-, grey- and brown dunes, the salt and lime content and the pH are decreasing. In grey- and brown dunes the formation of humus starts and a lower pH develops. On the grey dunes, which are sparsely vegetated, the air temperature, soil moisture, air moisture and evaporation are extremely fluctuating daily. The climate values in the brown dunes are relatively constant. There is a close connection between the ecology of the dune types and their specific function in coastal protection.Nomenclature of syntaxa follows Rothmaler (1976).     

Checklist of the families Lonchopteridae and Phoridae?of Finland (Insecta,Diptera)

A checklist of the Lonchopteridae and Phoridae recorded from Finland is presented.     

Ecological aspects of hermit crabs (Crustacea,Anomura, Paguroidea) off the northern coast of São Paulo State,Brazil

The occurrence of species of hermit crabs and their ecological distribution in soft bottoms off Ubatuba, São Paulo, Brazil were analyzed. To better understand the distribution of the species in relation to environmental factors, the similarity and species-diversity indexes were calculated. Paguroideans were sampled monthly from January through December 2000. The trawls were made with two otter-trawl nets at 13 different sites, at depths of 2–40 m. Water temperature, salinity, sediment texture, and organic matter content were measured. Gastropod shells occupied by hermit crabs were also assessed. A total of 1,238 specimens was collected, belonging to the families Diogenidae and Paguridae, comprising seven genera and thirteen species. The most abundant hermit crab species were Dardanus insignis (761 specimens) and Loxopagurus loxochelis (351 specimens). Phimochirus holthuisi is newly reported from the São Paulo coast. The highest diversity index was found for the shallower sites near rocky shores. The results of the grouping analysis for sites and species indicated three distinct groups for sites, and four groups for species. This suggests that the occurrence of these anomurans is associated with the environmental and biotic factors analyzed.     

Checklist of the families Scathophagidae,Fanniidae and?Muscidae of Finland (Insecta,Diptera)

A revised checklist of the Scathophagidae, Fanniidae and Muscidae recorded from Finland is presented. Phaonia amicula Villeneuve, 1922 is noted from Finland for the first time.     

Social aspects for sustainability assessment of technologies—challenges for social life cycle assessment (SLCA)

Purpose

Technologies can contribute to sustainable development (e.g., improving living conditions) and at the same time cause sustainability problems (e.g., emissions). Decisions on alternative technologies should thus ideally be based on the principle to minimize the latter. Analyzing environmental, economic, and social aspects related to technologies supports decisions by identifying the “more sustainable” technology. This paper focuses on social issues. First, it discusses the applicability of the social life cycle assessment (SLCA) guidelines for a comparative technology analysis, taking the example of two case studies in developing countries. Indicating technologies as “sustainable” also means that they are indeed operated over the expected lifetime, which, in development projects, is often not guaranteed. Consequently, social aspects related to implementation conditions should be considered in an SLCA study as well. Thus, a second focus is laid on identifying appropriate indicators to address these aspects.

Methods

First, the SLCA guidelines were examined with regard to applying this product-related approach to two real case studies (analysis of technologies/plants for water supply and for decentralized fuel production) for a comparative technology analysis. Suitable indicators are proposed. To address the second focus, a literature research on technology assessment and implementation in developing countries was conducted. Moreover, socioeconomic studies in the investigation areas of the case studies were consulted. Based on this, indicators addressing implementation conditions were identified from the SLCA guidelines and additional literature.

Results and discussion

The study shows social issues and indicators found in the SLCA guidelines and considered suitable for a comparative technology analysis in the case studies. However, for a sustainability assessment of technologies, especially in developing countries, further indicators are required to address technology implementation conditions. A set of additional social indicators like reported trust in institutions or fluctuation of personnel is proposed. Though these indicators were derived based on specific case studies, they can also be suggested to other technologies and are not necessarily limited to developing countries.

Conclusions

The study pointed out that an application of the SLCA guidelines considering the whole life cycle was not (yet) feasible for the case studies considered. This is mainly due to the lack of data. Regarding technology implementation, it was examined which indicators are available in this SLCA approach and which could additionally be integrated and applied. This is relevant as a potential contribution of technologies to sustainable development can only be achieved when the technologies are successfully implemented.     

The life history,production and food habits of Pontoporeia affinis Lindström (Crustacea: Amphipoda) in mesotrophic Lake Erken

The life history and feeding habits of Pontoporeia affinis Lindström were studied in mesotrophic Lake Erken during 1982 to 1983. The greatest densities and biomasses of P. affinis occurred at 12 m (662 ind./m² and 118.2 mg dw/m², respectively) with values decreasing at the shallower and deeper regions. The life cycle of Pontoporeia was one year, with recruitment occurring in April, at which time the majority of the population consisted of individuals <2 mm. Overall the gut content of Pontoporeia was predominantly composed of detritus (97.6%) with algae accounting for 2.3%. Annual production was highest at 12 m (386.2 mg dw/m²) and lowest at 16 m (8.1). The highest production occurred during September, coinciding with the autumn Bacillariophyceae bloom.