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1.
Heinz Löffler 《Hydrobiologia》1993,264(3):169-174
The northwestern area of the Pannonian Lowland extends into Austria. The climatic and hydrologic attributes of this biographic region promote the existence of extremely astatic bodies water lacking any fish and hence the occurrence of Anostraca, Notostraca, Laevicaudata and Spinicaudata. Zoogeographical and ecological features as well as the extinction of species due to anthropogenic influence are described.Dedicated to Prof. Dr F. Berger, Lunz, Austria, on the occasion of his 90th birthdayDedicated to Prof. Dr F. Berger, Lunz, Austria, on the occasion of his 90th birthday  相似文献   
2.
Tadpole shrimps (Notostraca) occur sporadically in temporary ponds and their survival there depends largely upon the drought-resistant eggs they produce. Environmental conditions conducive to hatching of eggs of Lepidurus couesii were investigated in the laboratory. Almost all eggs hatched best at 20 °C, whether desiccated for a short or long period, with a prior freezing shock or without such a shock, with intact shells. Eggs that endured a longer period of desiccation and eggs with abraded shells displayed a more equivocal response to different temperatures for hatching. Long-term hatchability of eggs was demonstrated. Time required for successful hatching was shortest at 20 °C, with no discernible difference between 17 °C and 25 °C. Both short- and long-term survival of populations of the species appears to be fostered by the adaptive response to temperature shown by the eggs.  相似文献   
3.
4.
Fluorescent-amplified fragment length polymorphism (FAFLP) fingerprinting assay was used to compare the genetic diversity within and between tadpole shrimps (Notostraca) populations of Lepidurus apus (n=7) and Triops cancriformis (n=2) from rain pools in Israel. Each ephemeral water body has revealed a unique fingerprint pattern with an entailed genetic drift between nearby ponds. High similarity of genotypic diversity within each geographic area led to three clusters of water bodies, north, south and center of Israel. FAFLP assays on several newly hatched individuals of T. cancriformis revealed high identity amongst kin, as compared to L. apus where newly hatched from the same maternal source showed high diversity. Results indicate that T. cancriformis populations from Israel are probably parthenogenetic as indicated by clonal structures. The higher genetic variability in the L. apus populations and in laboratory-hatched specimens indicates the existence of sexual reproduction.  相似文献   
5.
Petrov  Brigita  Petrov  Ivan 《Hydrobiologia》1997,359(1-3):29-35
The investigations of Anostraca, Notostraca and Conchostraca in Yugoslavia began after a great delay compared with other European countries. Intensive systematic investigations date back only to the 1970s.To date, 19 species have been recorded. All species, with the exception of Artemia salina, are faunal elements of the Pannonian region. Seven species, including Artemia salina, Branchinecta orientalis, Branchipus serbicus, Leptestheria dahalacensis, Limnadia lenticularis, Imnadia cristata and Imnadia panonica are known from single localities. Six species including Branchinecta ferox, Chirocephalus brevipalpis, Chirocephalus carnuntanus, Lepidurus apus, Eoleptestheria spinosa and Imnadia banatica have restricted distributions. Streptocephalus torvicornis and Cyzicus tetracerus are known from several localities, while Branchipus schaefferi, Chirocephalus diaphanus, Triops cancriformis and Leptestheria saetosaare common. Large branchiopods are mainly confined to anthropogenic landscapes, especially in the northern part of the country. Rare species inhabiting a single pond, or those with rather restricted distributions, are the most endangered and such species account for about 70% of the fauna. Limnadia lenticularis, Imnadia cristata and I. panonica have not been found for more than 20 years and they are probably extinct in Yugoslavia. Branchipus serbicus, Imnadia cristata and panonica have not been documented since being originally described. Eoleptestheria spinosa is currently the most endangered species since it only appears irregularly in small populations. At present, Branchinecta ferox, Chirocephalus carnuntanus and Imnadia banatica are the safest of the rare species as they regularly appear in large numbers. There are no large branchiopods on the List of protected animals in Yugoslavia. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
6.
Thiéry  Alain 《Hydrobiologia》1997,359(1-3):177-189
Cysts of three species of anostracans (Branchipusschaefferi, Chirocephalus diaphanus, and Tanymastigites perrieri), two species of Notostracans (Triops numidicus and Lepidurus apus) and one species of Spinicaudata (Leptestheriamayeti) were collected from the upper 2 cm of dry sediments at intervals along transects from a temporary pool in an arid zone of Morocco and from two ditches in France. The horizontal distribution of viable cysts was patchy and is discussed in relation to several ecological parameters prevailing during the aquatic phase. These include vegetation distribution, depth and morphometry of the pond, dominant wind pattern, and granularity of the sediments. The densities reached more than 1700 cysts of C. diaphanus per 100 cm2, and 1150 cysts of L. apus per 100 cm2 in the two ditches. The mean densities of cysts per 100 cm2 calculated for each transect ranged from 250 to 450 for C. diaphanous and 240 to 260 for L. apus (in the ditch populations) and about 1–6 for T. perrieri and L. mayeti, 3–15 for B. schaefferi, and16–58 for T. numidicus in the pool in Morocco. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
7.
Four branchiopod species occur on the Maltese Islands, viz. Branchipus schaefferi, B. visnyai, Cyzicus tetracerus and Triops cancriformis. All four live in freshwater pools, but it is noteworthy that, beside B. schaefferi, T. cancriformis was recorded from a mesohaline, coast-fringing habitat.  相似文献   
8.
Epizootic algae and Protozoa occur on the exoskeleton of fresh water branchiopods in temporary ponds in Morocco. Algal colonization seemed linked with turbid waters and access by the epibionts to the nutritive and oxygenated flows created by the rhythmical beat of the thoracic legs of the branchiopods. It also seemed linked to the mode of life (planktonic or benthic) of the host, and to their exposition to light. Appendages of anostracans, which swim ventral side up, bear a rich community of Chlorophytes, while in conchostracans, where body and appendages are protected by a bivalve carapace, and which swim ventral side down, epibionts colonize the valves, particularly near the hinge and umbo. The lack of algae on notostracans may result from their habit of living in the deeper part of ponds. Protozoans fixed on notostracan shields and on conchostracan valves or appendages, seem to benefit principally from the flow of nutrient- and oxygen-rich water created by the host.  相似文献   
9.
Jàn Brtek  Alain Thiéry 《Hydrobiologia》1995,298(1-3):263-280
The Large Branchiopod fauna of Europe consists of 72 species and sub-species: 50 anostracans, 8 notostracans, 12 spinicaudatans, and 2 laevicaudatans. Their geographical distribution is mapped, and remarks on ecological requirements of species are given.  相似文献   
10.
A new notostracan crustacean, Strudops goldenbergi gen. et sp. nov., is described from the well‐preserved terrestrial arthropod fauna of the Upper Devonian of Strud, Belgium. The fossil notostracan bears a close resemblance to modern notostracans in possessing a large, simple head shield covering almost half of the whole body, a set of phyllopodous thoracic appendages and a legless posterior abdomen with a telson bearing a caudal furca. The differentiation and relative size of mouthparts and limbs suggest that these specimens are all adults. The notostracans described herein are the earliest clear members of the total group Notostraca.  相似文献   
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