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At least 19 recordsLinked to original sources
PubMed2004

The effects of power station entrainment passage on three species of marine planktonic crustacean, Acartia tonsa (Copepoda), Crangon crangon (Decapoda) and Homarus gammarus (Decapoda).

Experiments have been undertaken exposing larval common shrimp (Crangon crangon) and lobster (Homarus gammarus) and adult copepods (Acartia tonsa) to the key stresses of entrainment within power-station cooling-water systems. The apparatus has enabled the testing of mechanical, thermal, chlorine and realistic pressure effects both alone and in combination, the range of stressors spanning the standard conditions found within a temperate coastal direct-cooled power station. Mechanical stresses affected only lobster larvae, pressure changes affected only the Acartia adults. Residual chlorine caused significant mortality of Acartia and shrimp larvae, but had no effect on lobster larvae even at 1 ppm. The temperature increment significantly affected all three species, with a synergistic effect on chlorine sensitivity in the shrimp larvae, but only temperatures higher than would be experienced in a normally-operating power station affected the copepods. The majority of individuals of each species would survive passage through a power-station system under normal conditions. It is notable that, within the species tested, generalizations from the responses of one species to those of another are not valid.

Animals↗
PubMed1996

Annotated list of species of marine crustaceans (Decapoda and Stomatopoda) from Golfo Dulce, Costa Rica.

The present study is an annotated list of the marine crustaceans (Decapoda and Stomatopoda) from Golfo Dulce, Costa Rica, collected during the RV Victor Hensen Cruise 1993-1994, at depths ranging from 20 to 260 m. Stomatopoda was represented by one family and two species. Decapoda was represented by 12 families and 21 species. Two new records for Costa Rica, Cancer johngarthi and Lysmata californica are reported. This increases the reported marine crustaceans of Golfo Dulce to three species of Stomatopoda and sixty-six of Decapoda (a complete checklist in included). A list of species reported in the literature from the gulf is also included.

Animals↗
PubMed2006

[Laurentaeglyphea, a new genus for the second recent species of Glypheid recently discovered. (Crustacea Decapoda Glypheidae)].

In 1975, a recent member of a large group of Crustacea Decapoda was described as Neoglyphea inopinata Forest & de Saint Laurent, until now only known as fossils and presumed extinct since the Eocene. The only known specimen had been collected in the Philippine waters, in 1908, at a depth of 200 m. During the next years, three oceanographical expeditions gave more adult specimens, allowing complete study of the species. From its morphology, it appeared that the status attributed to glypheids in the past in the classification of Decapoda Crustacea was quite erroneous. This group, until then considered as related to Palinurids (rock lobsters) was in fact much closer to Astacids (lobster, crayfish, etc.). In 1982, N. inopinata was recorded from the other side of Equator, from the Timor Sea. In October 2005, a second living species of glypheid was discovered southwest of New Caledonia. It was named Neoglyphea neocaledonica B. Richer de Forges, 2006. However, important and significant differences set apart the two species, especially the ornamentation of the cephalothorax, the conformation of the cephalic part and the proportions of epistom and thoracic appendages, being much more robust. It seems justified to establish, for the more recently described species, a new genus, Laurentaeglyphea, much closer to fossil forms.

Animals↗
PubMed2006

The complete mitochondrial genome of the mantid shrimp Harpiosquilla harpax, and a phylogenetic investigation of the Decapoda using mitochondrial sequences.

The complete mitochondrial DNA sequence was determined for the mantid shrimp Harpiosquilla harpax. These data demonstrate that the H. harpax mitochondrial genome is a 15,714 bp circular molecule and encodes the typical 37 metazoan mitochondrial genes (13 protein-coding, 22 tRNA, and two rRNA genes). The gene arrangement of H. harpax is consistent with that of the putative arthropod ancestral gene order as depicted by Limulus polyphemus. H. harpax was employed as an outgroup taxon for a phylogenetic investigation of the Decapoda using sequences from complete mitochondrial genomes. Whilst our results are largely in agreement with current taxonomic treatments, the relationships indicated among the reptantian decapods are novel. Our results provide strong statistical support for a sister-group relationship between the Achelata and the Astacida. These findings not only refute previous phylogenetic hypotheses, but also have serious implications for the interpretation of morphological and developmental evolution in the Decapoda. In addition we also investigated the effects of outgroup selection on the resolution of ingroup relationships. We found outgroup choice to significantly influence tree topology thus reinforcing the importance of appropriate outgroup selection in phylogenetic studies.

Animals↗
PubMed2002

Complete mitochondrial DNA sequence of the Japanese spiny lobster, Panulirus japonicus (Crustacea: Decapoda).

We determined the complete nucleotide sequence of the mitochondrial genome for a Japanese spiny lobster, Panulirus japonicus (Crustacea: Decapoda). The entire genome was amplified using long polymerase chain reaction, and the products were subsequently used as templates for direct sequencing using a primer-walking strategy. The genome (15,717 base pairs) contained the same 37 genes (two ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes) plus the putative control region as found in other arthropods, with the gene order identical to that of typical arthropods. Preliminary phylogenetic analyses of selected arthropods using concatenated amino acid sequences of the 13 protein-coding genes strongly supported monophyly of Decapoda species and confidently rejected "Macroura", a conventional taxon that shares an elongated abdominal body.

Amino Acid Sequence↗
PubMed2001

Ultrastructural aspects of a new species, Vavraia mediterranica (Microsporidia, Pleistophoridae), parasite of the French Mediterranean shrimp, Crangon crangon (Crustacea, Decapoda).

The life cycle stages of a new species of the genus Vavraia (Microsporidia, Pleistophoridae), which parasitizes the shrimp Crangon crangon (Crustacea, Decapoda), were examined by light and electron microscopy. This parasite was monomorphic with polysporous sporogony and developed in the skeletal muscle of the host. The multinucleate sporogonial plasmodium divided by plasmotomy and multiple division into uninucleate sporoblasts. All stages were surrounded by a thick and amorphous dense coat external to the plasmalemma. This structure gradually became a merontogenetic sporophorous vacuole (MSV) where the sporonts developed into sporoblasts. The MSV was filled with episporontal granular secretory products and eventually contained up to 50 uninucleate spores. During spore morphogenesis, these episporontal granular products within the MSV became organized as episporontal tubular-like structures. In transverse sections, these structures showed a mean diameter of 1.0 microm, but disappeared during the final phase of the spore maturation. Mature spores were ellipsoidal to slightly pyriform and measured 2.30 x 1.41 microm. The polar filament was anisofilar and consisted of a single coil with six to seven turns (rarely five). This new species is named Vavraia mediterranica n. sp.

Animals↗
PubMed2003

Toxic effects of microcystins in the hepatopancreas of the estuarine crab Chasmagnathus granulatus (Decapoda, Grapsidae).

Microcystins are toxins produced by cyanobacteria, being toxic to aquatic fauna. It was evaluated alternative mechanisms of microcystins toxicity, including oxidative stress and histopathology in the hepatopancreas of the estuarine crab Chasmagnathus granulatus (Decapoda, Grapsidae). Microcystins was administered to crabs (MIC group) over 1 week, whereas the control (CTR group) received the saline from cyanobacteria culture medium. At day 7, catalase activity was higher in the MIC than in the CTR group, although a decrease of activity was verified in both groups with respect to time 0. Glutathione-S-transferase activity augmented in MIC with respect to CTR, suggesting a higher conjugation rate of the toxins with glutathione. No differences were detected in the superoxide dismutase activity. Lipid peroxidation remained stable in both groups. Histopathological analyses showed that the number of B cells decreased significantly in the CTR as a possible effect of starvation, while no significant change was observed in the MIC group. The hepatopancreas from the MIC group exhibited some necrotic tubules and melanin-like deposits. Overall, results showed that some enzymes of the antioxidant defense system were activated after microcystins exposure, this response being able to maintain lipid peroxidation levels, but insufficient to completely prevent histological damage.

Animals↗
PubMedDate not supplied

Effects of extracts from the cyanobacterium Microcystis aeruginosa on ion regulation and gill Na+,K+-ATPase and K+-dependent phosphatase activities of the estuarine crab Chasmagnathus granulata (Decapoda, Grapsidae).

Recent discoveries indicate that microcystins affect enzymes, such as Na(+),K(+)-ATPase, involved in ion regulation of aquatic animals, through K(+)-dependent phosphatase inhibition. In vitro studies showed the inhibitory effect of Microcystis aeruginosa extracts on Na(+),K(+)-ATPase and K(+)-dependent phosphatase activities in gills of Chasmagnathus granulata (Decapoda, Grapsidae). Extracts of M. aeruginosa were prepared from lyophilized or cultures cells of the cyanobacterium. For lyophilized cells, IC(50) values were estimated as 0.46 microg/L (95% confidence interval [CI]=0.40-0.52 microg/L) and 1.31 microg/L (95% CI=1.14-1.51 microg/L) for Na(+),K(+)-ATPase and K(+)-dependent phosphatase, respectively. However, extracts prepared from cultured cells presented a much lower inhibitory potency against both enzymes. Gas chromatography revealed long-chain fatty acids in the lyophilized cell extracts, indicating that they are in part responsible for the enzyme inhibition. In vivo studies showed that the toxin inhibited Na(+),K(+)-ATPase activity in anterior gills, whereas an increased augmented activity of glutathione-S-transferase was observed in both kind of gills, indicating that the crab has increased its ability to conjugate the toxin. No significant differences in hemolymph sodium or chloride concentration were detected. This result is in agreement with the lack of effects of microcystin on Na(+),K(+)-ATPase activity of posterior (osmoregulating) gills.

Animals↗
PubMed2004

B chromosomes in Crustacea Decapoda.

Among crustacean Decapoda numerical chromosome variability is frequent, and it has been hypothesized that the presence of supernumerary chromosomes accounts for this variability. Thanks to the improvement of cytogenetic analysis by chromosomal banding techniques, supernumerary B chromosomes (Bs) have been demonstrated in Nephrops norvegicus, Homarus americanus,Palinurus elephas and P. mauritanicus, belonging to different crustacean families. In all four species Bs were variable in number, mainly heterochromatic and undigested by various endonucleases, and in meiosis they showed non-Mendelian segregation. Compared to the other chromosomes of the complement, the Bs are very small in almost all species, but some of them were very large in N. norvegicus.

Chromosomes↗
PubMed2002

A new species of the genus Rimicaris (Alvinocarididae: Caridea: Decapoda) from the active hydrothermal vent field, "Kairei Field," on the Central Indian Ridge, the Indian Ocean.

Rimicaris kairei new species (Alvinocarididae: Caridea: Decapoda) is described based on materials, from the active hydrothermal vent field, "Kairei Field," on the Central Indian Ridge, the Indian Ocean. The new species is clearly distinguishable from the unique congener, R. exoculata Williams & Rona, 1986, which is known from the Atlantic Ocean. The following morphological differences were identified: (1) all punctations on carapace strongly ornamented by tufts of short stiff setae in R. exoculata, whereas without any setae in R. kairei; (2) antennal flagella in R. exoculata shorter than in R. kairei; (3) walking legs in R. exoculata more robust than in R. kairei.

Animals↗
PubMed2004

A waterborne behavioral cue for the actinotroch larva of Phoronis pallida (Phoronida) produced by Upogebia pugettensis (Decapoda: Thalassinidea).

Phoronis pallida (Phoronida) occurs as a commensal within the burrow of Upogebia pugettensis (Decapoda: Thalassinidea). Upogebia-conditioned seawater (UCSW) induced an exploratory swimming behavior in competent larvae of P. pallida in a dosage-dependent manner. This behavior included a significant increase in swimming speed that was directed downward, along with the repeated probing of the bottom with the sensory portion of the oral hood. The waterborne cue from the shrimp was present in the gut effluent, and the swimming behavior was not the result of the elevated ammonia concentration. Molecular weight separation of the UCSW estimated that the cue was between 10 and 50 kDa. Enzymatic treatments showed that the cue's activity could be eliminated by arginase and significantly reduced by lipase. Competent larvae were also induced to metamorphose when exposed to 20 mM CsCl for 30 min. Larvae did not respond to CsCl when cultured about 4 weeks past the onset of competence. Compared with actinotroch larvae of other phoronid species, P. pallida larvae exhibit greater behavioral specificity and neuronal differences within the hood sense organ. These anatomical and behavioral differences may have been maintained through a coevolutionary process among P. pallida and species of thalassinid shrimps that share Upogebia life-history characteristics.

Animals↗
PubMed2000

Quantification of the age-pigment lipofuscin in brains of known-age, pond-reared prawns Penaeus japonicus (Crustacea, decapoda).

A quantitative study of the lipofuscin content was carried out by image analysis in brains of known-age, pond-reared Penaeus japonicus (Crustacea, Decapoda) with the aim of assessing the applicability of the lipofuscin technique as an estimator of the physiological age in penaeids. With this purpose, three distinct measurements of lipofuscin levels (% area fraction, granule density and mean granule size) were recorded in ten sections of the olfactory lobe cell mass (OLCM) per animal. The image analysis was based on the autofluorescence emitted by the pigment, which accentuates the contrast between the lipofuscin granules and the background tissue. The concentration of lipofuscin increased significantly with age and was independent of sex. The relationship between age and lipofuscin concentration (area fraction and granule density) was best described by a seasonalized von Bertalanffy function, since the accumulation rate of the pigment dramatically slowed down in fall-winter, probably as a result of reduced seasonal metabolism. The present results confirm the potential of the lipofuscin method in the estimation of physiological age in penaeids and suggest that the application of this methodology can be useful in studies of age structure in wild populations and in the assessment of natural resources. J. Exp. Zool. 286:120-130, 2000.

Animals↗
PubMed1997

The molecular evolution of visual pigments of freshwater crayfishes (Decapoda: Cambaridae).

This study examines the diverse maximum wavelength absorption (lambdamax) found in crayfishes (Decapoda: Cambaridae and Parastacidae) and the associated genetic variation in their opsin locus. We measured the wavelength absorption in the photoreceptors of six species that inhabit environments of different light intensities (i.e., burrows, streams, standing waters, and subterranean waters). Our results indicate that there is relatively little variation in lambdamax (522-530 nm) among species from different genera and families. The existing variation did not correlate with the habitat differences of the crayfishes studied. We simultaneously sequenced the rhodopsin gene to identify the amino acid replacements that affect shifts in maximum wavelength absorption. We then related these to changes that correlated with shifts in lambdamax by reconstructing ancestral character states using a maximum-likelihood approach. Using amino acid sequences obtained from five species (all were 301 amino acids in length), we identified a number of candidates for producing shifts of 4 to 8 nm in lambdamax. These amino acid replacements occurred in similar regions to those involved in spectral shifts in vertebrates.

Amino Acid Sequence↗
PubMed1991

Biochemical and histochemical observations on effects of low-level heavy metal load (lead, cadmium) in different organ systems of the freshwater crayfish, Astacus astacus L. (Crustacea: Decapoda).

The effects of low-level lead (20 micrograms/liter) and/or cadmium (2 micrograms/liter) exposure on the structure and function of different organ systems of the freshwater crayfish. Astacus astacus L. (Crustacea: Decapoda) were estimated by several biochemical and histochemical methods. The animals were incubated during 10 weeks (max.) at a temperature of 10 degrees C and a normal diurnal rhythm. Lead accumulated in high amounts especially in the digestive gland, carapax, and gills, whereas the hindgut and musculature exhibited very low lead levels. Cadmium accumulated particularly in the digestive gland and gills. Lead and cadmium levels were definitely lower in the digestive gland, gills, and carapax of animals incubated in water containing a double, i.e., lead and cadmium load, than in animals kept in water containing only one of these heavy metals. Histochemically both metals could be visualized in a typical distribution within the tissues, such as the carapax, digestive gland, or gills. After several weeks of poisoning, all organs, but especially the digestive gland, showed severe structural impairment. The activities of oxidative enzymes in the digestive gland and gills were significantly lowered after 2 weeks of incubation. Enzyme histochemical evaluation demonstrated changes of reaction intensities within the organs as compared to the controls. GSH S-transferase activities and GSH contents were also distinctly decreased following lead and/or cadmium intoxification. The histochemical demonstration of SH and S-S groups exhibited a stronger staining reaction after 10 weeks of exposure, especially in digestive gland and gills. The results obtained are discussed in view of the specific impairment of function of the organ systems studied, as related to the typical biology of the animal species tested.

Animals↗
PubMed2005

Biochemical and physiological responses after exposure to microcystins in the crab Chasmagnathus granulatus (Decapoda, Brachyura).

Microcystins are usually the predominant cyanotoxins present in both drinking and recreational waters after cyanobacterial blooms. Their classic toxic effect is hepatotoxicity through inhibition of serine/threonine phosphatases. However, recent studies also reported oxidative stress generation and disruption of ion regulation in aquatic organisms after microcystins exposure. In the present study, aqueous extracts of Microcystis aeruginosa were administered to the estuarine crab Chasmagnathus granulatus (Decapoda, Brachyura) by gavage in variable doses (from 34 to 860 microg kg(-1)) and exposure times (6, 12, and 72 h). A control group was exposed to saline solution. Analyzed variables included oxygen consumption, lipid peroxidation (LPO), enzyme activities (glutathione S-transferases or GST; alanine aminotransferase or ALT; aspartate aminotransferase or AST; and lactate dehydrogenase or LDH), glycogen, and microcystins content. Oxygen consumption increased in organisms exposed for 12h to 860 microg kg(-1) of microcystins and a similar result was observed after 72 h at doses equal to or higher than 34 microg kg(-1). LPO levels increased in doses equal to or higher than 34 microg kg(-1) after 72 h. GST and LDH activities increased after 12 h (at a dose of 860 microg kg(-1)), but ALT and AST activities remained unaltered in all experimental conditions. Glycogen content decreased after 72 h exposure at doses equal to or higher than 172 microg kg(-1). After 12h of exposure to 860 microg kg(-1) of microcystins, the concentration found in the hepatopancreas of C. granulatus was 13.17+/-0.56 microg kg(-1). In crabs exposed to doses higher than 172 microg kg(-1) during 72 h this value raised to 32.14+/-4.12 microg kg(-1). The obtained results indicated that microcystins exposure led the tissue to an oxidative stress condition (high LPO levels), at least in part favored by the augment of oxygen consumption, altering the glycogen metabolism. GST responses were only observed in the short-term experiment (12 h) and no effect on classical markers of vertebrate liver damage (ALT and AST) was observed. Although the hepatopancreas from C. granulatus accumulated a relatively low concentration of toxins, it was enough to induce physiological and biochemical disturbances.

Animals↗
PubMed2004

Complete mitochondrial DNA sequence of the Australian freshwater crayfish, Cherax destructor (Crustacea: Decapoda: Parastacidae): a novel gene order revealed.

The complete mitochondrial DNA sequence was determined for the Australian freshwater crayfish Cherax destructor (Crustacea: Decapoda: Parastacidae). The 15,895-bp genome is circular with the same gene composition as that found in other metazoans. However, we report a novel gene arrangement with respect to the putative arthropod ancestral gene order and all other arthropod mitochondrial genomes sequenced to date. It is apparent that 11 genes have been translocated (ND1, ND4, ND4L, Cyt b, srRNA, and tRNAs Ser(UGA), Leu(CUN), Ile, Cys, Pro, and Val), two of which have also undergone inversions (tRNAs Pro and Val). The 'duplication/random loss' mechanism is a plausible model for the observed translocations, while 'intramitochondrial recombination' may account for the gene inversions. In addition, the arrangement of rRNA genes is incompatible with current mitochondrial transcription models, and suggests that a different transcription mechanism may operate in C. destructor.

Animals↗
PubMed2003

Complete mitochondrial DNA sequence of the swimming crab, Portunus trituberculatus (Crustacea: Decapoda: Brachyura).

We determined the complete mitochondrial DNA sequence for a swimming crab Portunus trituberculatus (Miers, 1876) (Crustacea: Decapoda: Brachyura). The entire genome was amplified using a long PCR technique, and the products were subsequently used as templates for direct sequencing using a primer walking strategy. The genome (16,026 bp) contained the same 37 genes (two rRNAs, 22 tRNAs, and 13 proteins) plus the putative control region as found in other arthropods. The gene order of P. trituberculatus was largely identical to those so far obtained for other arthropods such as Drosophila yakuba, although the relative position of the tRNA(His) gene differed from all other arthropods studied so far. While the tRNA(His) gene in other arthropod mitochondrial genomes is located between the ND4 and ND5 genes, that of P. trituberculatus was found between the tRNA(Glu) and the tRNA(Phe) genes, which were located downstream of the ND5 gene. The present gene order could have resulted from tandem duplication occurring in the tRNA(Phe)-ND5-tRNA(His) region (typical gene order in other arthropods) and following deletions of redundant genes. This is the first report of a mitochondrial genome of a brachyuran crab, one of the most diversified and economically important groups of crustaceans.

Animals↗
PubMed2002

Organic and inorganic compound variations in haemolymph, epidermal tissue and cuticle over the molt cycle in Scylla serrata (Decapoda).

Analysis of organic and inorganic compounds in haemolymph, epidermal tissue and cuticle, allowed the correlation of their content variation during the molt cycle in Scylla serrata (Decapoda). The extrusion of carbohydrate, chitin, H(2)O- and NaOH-soluble proteins of the epidermal tissue from D2 stage on suggested an early formation of the organic fraction in the new cuticle. The additional secretion of HCl-soluble protein, glycosaminoglycans, calcium, phosphorus and sulfur in D2-D3 stages suggests mineral nucleation shortly before or at ecdysis. This is consistent with the dominant content of proteins and chitin associated with peaks of carbohydrates and GAG-sulfur groups detected in the cuticle immediately after ecdysis. Furthermore, the maximal phosphorus content at this moment suggests calcium, magnesium and manganese phosphate deposits. After an intense accumulation of calcium, chitin and sharp decrease of protein from A to B stages, a constant rate of their deposition in intermolt and dissolution in premolt occurred. The variations concerning proteins, carbohydrates, glycosaminoglycans, calcium, magnesium and sulfur in the haemolymph, before and after ecdysis, suggest a transitory phenomenon for calcium binding and releasing. Other major elements such as, sodium, potassium and chloride may function as osmotic regulators in the haemolymph and in epidermal compartments. The copper profile presented an indicator role for variations of osmolality over the molt cycle.

Animals↗