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Cyclops Strenuus
''Cyclops strenuus'' (Fisher) is a common species of copepod in small water bodies in central Europe. The life-cycle of ''C. strenuus'' varies depending on habitat type and climate. In some habitat year round reproduction occurs. While in others one or two distinct generations exist with summer diapause. During diapause copepodid IV resting stages are produced that are largely inactive. These resting stages can survive in mud, to survive dry summer periods. During autumn, with a change in environmental conditions, resting stages become more active again and develop further into adult copepods. Ecology ''Cyclops strenuus'' occurs in temperate habitats. Normal activity occurs between 3 and 21 °C and temperatures above 26 °C are actively avoided. It is also a common intermediate host of cestode parasites, such as ''Schistocephalus solidus ''Schistocephalus solidus'' is a tapeworm of fish, fish-eating birds and rodents. This hermaphroditic parasite belongs to the Eucestoda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor), a number of species have parasitic phases, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, and puddles, damp moss, or water-filled recesses (phytotelmata) of plants such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as Ecological indicator, biodiversity indicators. As with other crustaceans, copepods have a larval form. For copepods, the egg hatches into a Crustacean larvae#Nauplius, nauplius form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diapause
In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press It is a physiological state with very specific initiating and inhibiting conditions. The mechanism is a means of surviving predictable, unfavorable environmental conditions, such as temperature extremes, drought, or reduced food availability. Diapause is observed in all the life stages of arthropods, especially insects. Embryonic diapause, a somewhat similar phenomenon, occurs in over 130 species of mammals, possibly even in humans, and in the embryos of many of the oviparous species of fish in the order Cyprinodontiformes. Activity levels of diapausing stages can vary considerably among species. Diapause may occur in a completely immobile stage, such as the pupae and eggs, or it may occur in very active stages that undergo extensive migrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copepodid
Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow. The larvae of crustaceans often bear little resemblance to the adult, and there are still cases where it is not known what larvae will grow into what adults. This is especially true of crustaceans which live as benthic adults (on the sea bed), more-so than where the larvae are planktonic, and thereby easily caught. Many crustacean larvae were not immediately recognised as larvae when they were discovered, and were described as new genera and species. The names of these genera have become generalised to cover specific larval stages across wide groups of crustaceans, such as ''zoea'' and ''nauplius''. Other terms described forms which are only found in particular groups, such as the ''glaucothoe'' of hermit crabs, or the '' phyllosoma'' of sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cestoda
Cestoda is a class of parasitic worms in the flatworm phylum (Platyhelminthes). Most of the species—and the best-known—are those in the subclass Eucestoda; they are ribbon-like worms as adults, known as tapeworms. Their bodies consist of many similar units known as proglottids—essentially packages of eggs which are regularly shed into the environment to infect other organisms. Species of the other subclass, Cestodaria, are mainly fish infecting parasites. All cestodes are parasitic; many have complex life histories, including a stage in a definitive (main) host in which the adults grow and reproduce, often for years, and one or two intermediate stages in which the larvae develop in other hosts. Typically the adults live in the digestive tracts of vertebrates, while the larvae often live in the bodies of other animals, either vertebrates or invertebrates. For example, '' Diphyllobothrium'' has at least two intermediate hosts, a crustacean and then one or more freshwater fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schistocephalus Solidus
''Schistocephalus solidus'' is a tapeworm of fish, fish-eating birds and rodents. This hermaphroditic parasite belongs to the Eucestoda subclass, of class Cestoda. This species has been used to demonstrate that cross-fertilization produces a higher infective success rate than self-fertilization. Life cycle It parasitizes fish and fish-eating water birds. The fish-eating water bird is the definitive host, and reproduction occurs in the bird's intestine. Eggs of the tapeworm are passed with the bird's feces and hatch in the water, where the first larval stage, the coracidium, is produced. The coracidium is then ingested by the first intermediate host, a cyclopoid copepod (e.g. ''Macrocyclops albidus''). The second larval stage then subsequently develops in the tissue of this host. Within one to two weeks, the infected copepod is ingested by the second intermediate host, the three-spined stickleback, ''Gasterosteus aculeatus''. The third larval stage, the plerocercoid, grows in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of Europe
The fauna of Europe is all the animals living in Europe and its surrounding seas and islands. Since there is no natural biogeographic boundary in the east and south between Europe and Asia, the term "fauna of Europe" is somewhat elusive. Europe is the western part of the Palearctic realm (which in turn is part of the Holarctic). Lying within the temperate region, (north of the equator) the wildlife is not as rich as in the hottest regions, but is nevertheless diverse due to the variety of habitats and the faunal richness of Eurasia as a whole. Before the arrival of humans European fauna was more diverse and widespread than today. The European megafauna of today is much reduced from its former numbers. The Holocene extinction drastically reduced numbers and distribution of megafauna and continues to (such as with wolves and bears). Many of these species still exist in smaller numbers, while others thrive in the developed continent free from natural predators, with the former threaten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
