Crustacea, crustaceans

The Mandibulata is by far the largest group of arthropods, since it contains the insects. Animals in this group have two or three body segments, one or two pairs of antennae, and one pair of mandibles. The subphylum Mandibulata is divided into six classes, the largest two of which are the Hexapoda (insects) and Crustacea (crustaceans). 

Anostraca CR CRUSTACEA Crustacean (NODC) NODC Taxonomic Code 6104010101... 

Crustacea (Crustaceans) 40000 Free-living, diverse, mostly aquatic, widespread... 

The phylum Arthropoda includes the classes Diplopoda (millipedes), Chilopoda (centipedes), Crustacea (see Chapter 3), and Insecta (see Chapter 1). All luminous arthropods other than crustaceans are terrestrial, and not very many luminous millipedes and centipedes are known. The luminescence of millipedes is usually intracellular, whereas luminous centipedes discharge luminous secretion. Substantial chemical studies have been made only with the millipede Luminodesmus sequoiae and the centipede Orphaneus brevilabiatus, of which the latter is discussed in the Section 10.3. 

Crustacea Arthropods, Crustaceans, Insects Lectins, PO, Leucine rich repeats, Toll, Tol interleukin receptors, AMPs, complement... 

Crustacean A member of the class Crustacea aquatic invertebrates with jointed appendages and having gills and two pairs of antennae. 

In adult insects the prothoracic gland ceases to function, and the gonads take over ecdysteroid production. In adult Crustacea moulting continues and the Y-organs continue to function, so that there is limited evidence about alternative sites of production. Lafont and Mathieu39 point out that there is no clear evidence that crustacean ovaries produce ecdysteroids, and there is still less evidence that males produce them. 

In several fish species and one marine crustacean, taurine conjugates of xenobiotic carboxylic acids have been Isolated from urine (fish) or hepatopancreas (Crustacea) and subjected to unequivocal chemical characterization (77-82). Table VIZ shows which acids are conjugated with taurine in some marine species. 

Water-borne Administration. For water-borne administration, drugs are usually prepared in a bath in which the animals are held for a period of time before introducing fresh untreated water. It is important to ensure that the drug is completely dissolved in the well-mixed water before adding the animal. This method of exposure has not to our knowledge been used to study drug uptake by crustaceans, but has been widely used for studies of the uptake of pesticides and environmental pollutants by Crustacea 74). 

Isolation from Dosed Crustacea. Metabolites are usually excreted in feces and urine after formation in the hepatopancreas, antennal gland or other sites. The identification of metabolites in crustaceans follows established procedures, i.e., the expected metabolites are predicted from the drug s structure, or from studies with other species, and methods are developed for the extraction and separation of the parent drug and the expected metabolites. Metabolites may then be identified by cochromatography with known metabolite, standards, and by various spectroscopic procedures, such as mass and nuclear magnetic resonance. The major difficulty in working with crustaceans lies in isolating metabolites from hepatopancreas, where most of the metabolites of lipophilic... 

The phylum Arthropoda contains a number of subphyla, such as Chelicerata (scorpions, spiders and mites), Myriapoda (centipedes and millipedes), Crustacea (crabs, shrimps and woodlice) and Hexapoda (springtails, bristletails and insects). The most conspicuous and well-known members of the Arthropoda are, undoubtedly, the crustaceans and... 

The zooplankton include a number of major taxonomic groups of animals, either for their entire life cycle or for short periods, as in the case of the larval stages of some fishes, polychaetes, crustaceans and molluscs. From among these types of zooplankton by far the most important group are the Crustacea, and of these, the copepods are the most predominant and have thus received most attention (Crisp, 1975). 

Fig. 1.1 Phylogeny of crustaceans, highlighting in bold the taxa that have been subject to research on chemical communication. Only those subtaxa of Malacostraca and Decapoda are shown that have been subject to chemical communication research. Phylogeny was modified after Tree of life (http //tolweb.org/Crustacea), and Dixon et al. (2003)...

In crustaceans, communication is mainly through the visual, chemical, and mechanical channels (see e.g., Mead and Caldwell, Chap. 11 Christy and Rittschof, Chap. 16 Clayton 2008). Whereas visual communication is mainly limited to species from terrestrial and clear-water environments, chemical communication can occur under most environmental conditions. Not surprisingly, studies on chemical communication dominate the literature. Of a total of 76 publications on crustacean communication (with the keywords communicat and Crustacea ) published between 1990 and 2010, 43 were on chemical communication, 24 on visual communication, and only 9 on mechanical/acoustic communication (Web of Science 2010). 

Atema J, Steinbach MA (2007) Chemical communication and social behavior of the lobster Homarus americanus and other decapod Crustacea. In Duffy JE, Thiel M (eds) Evolutionary ecology of social and sexual systems - crustaceans as model organisms. Oxford University Press, New York, pp 115-144... 

Dunham PJ, Hurshman AM (1991) Precopulatory mate guarding in aquatic Crustacea Gammarus lawrencianus as a model system. In Bauer RT, Martin JW (eds) Crustacean sexual biology. Columbia University Press, New York, pp 50-66... 

Willis JH (1999) Cuticular proteins in insects and crustaceans. Am Zool 39 600-609 Winsor GL, Innes DJ (2002) Sexual reproduction in Daphnia pulex (Crustacea Cladocera) ... 

Borst DW, Laufer H, Landau M, Chang ES, Hertz WA, Baker FC, Schooley DA (1987) Methyl farnesoate and its role in crustacean reproduction and development. Insect Biochem 17 1123-1127 Browdy CL, Fainzilber M, Tom M, Loya Y, Lubzens E (1990) Vitellin synthesis in relation to oogenesis in in vitro incubated ovaries of Penaeus semisulatus (Crustacea Decapoda, Penaeidae). J Exp Zool (in press)... 

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