| radionuclide concentrations in benthic invertebrates from amchitka and kiska islands in the aleutian chain, alaska. | concentrations of 13 radionuclides (137cs, 129i, 60co, 152eu, 90sr, 99tc, 241am, 238pu, 239,249pu, 234u, 235u, 236u, 238u) were examined in seven species of invertebrates from amchitka and kiska islands, in the aleutian chain of alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. amchitka island was the site of three underground nuclear test (1965-1971), and we tested the null hypotheses that there were no differences in radionuclide concentrat ... | 2007 | 17057992 |
| redescription of dicyemennea nouveli (phylum: dicyemida) from enteroctopus dofleini (mollusca: cephalopoda: octopoda). | a species of dicyemid mesozoan is redescribed from the giant pacific octopus, enteroctopus dofleini (wülker, 1910), collected off iwase in toyama bay, honshu, japan. dicyemennea nouveli mcconnaughey, 1959, is a large species that reaches about 12,000 microm in length. this species lives in folds of the renal appendages. the vermiform stages are characterized as having 30-41 peripheral cells, a conical calotte, and an axial cell that extends to the middle of the metapolar cells. an anterior abort ... | 2008 | 18576827 |
| rearing and growth of the octopus robsonella fontaniana (cephalopoda: octopodidae) from planktonic hatchlings to benthic juveniles. | globally, octopus larviculture is one of the challenges faced in the attempt to diversify aquaculture and achieve cephalopod farming. currently, only juveniles of octopus vulgaris, octopus joubini, and enteroctopus dofleini have been obtained at an experimental level. this is the first study to look at the characteristics of planktonic and benthic robsonella fontaniana juveniles in an effort to analyze the morphometric changes occurring during their planktonic and benthic phases and to explore t ... | 2010 | 20413796 |
| sperm ultrastructure of the hydrothermal vent octopod vulcanoctopus hydrothermalis. | sperm ultrastructure of the deep-sea hydrothermal vent octopod vulcanoctopus hydrothermalis has been carried out by transmission electron microscopy. spermatozoa of this species have the shortest head observed so far in octopodids. the acrosome possesses a helix with six gyres. the rod-shaped nucleus is short and wide in relation with other octopodids. noteworthy features along the nucleus are the regularly disposed dense bands of cytoplasm, which have not been observed before in octopodids. the ... | 2010 | 20623654 |
| fecal hormones measured within giant pacific octopuses enteroctopus dofleini. | the captive husbandry of giant pacific octopuses enteroctopus dofleini is well understood, but their endocrine signatures are not well documented. the major vertebrate reproductive hormones--estrogen, progesterone, and testosterone--and the stress-related hormone corticosterone are relatively well known for many vertebrate species. however, few studies on these hormones within invertebrates have been conducted. our hypothesis was that endocrine signatures within octopuses are similar to those fo ... | 2010 | 21192544 |
| evolution of molluscan hemocyanin structures. | hemocyanin transports oxygen in the hemolymph of many molluscs and arthropods and is therefore a central physiological factor in these animals. molluscan hemocyanin molecules are oligomers composed of many protein subunits that in turn encompass subsets of distinct functional units. the structure and evolution of molluscan hemocyanin have been studied for decades, but it required the recent progress in dna sequencing, x-ray crystallography and 3d electron microscopy to produce a detailed view of ... | 2013 | 23454609 |
| functional chondroitin sulfate from enteroctopus dofleini containing a 3-o-sulfo glucuronic acid residue. | there are several reports that chondroitin sulfate containing k-type units [glca (3s)-galnac (4s)] exhibiting similar levels of neurite outgrowth promoting activities as cs having high amounts of b-, d- and e-type disulfated disaccharides. although cs containing k-type units possess important biological activities, there are only few sources, such as king crab cartilage, squid cartilage or sea cucumber. in this study, cs containing 13.9% of k-type units was found in octopus (enteroctopus doflein ... | 2015 | 26428158 |
| octopuses (enteroctopus dofleini) recognize individual humans. | this study exposed 8 enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. one person consistently fed the octopuses and the other touched them with a bristly stick. each human recorded octopus body patterns, behaviors, and respiration rates directly after each treatment. at the end of 2 weeks, a body pattern (a dark eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly diffe ... | 2010 | 20563906 |
| retrospective review of mortality in giant pacific octopus (enteroctopus dofleini). | the giant pacific octopus (enteroctopus dofleini) is a popular exhibit species in public display aquaria, but information on health and disease is limited. this retrospective review evaluates time in collection and describes antemortem clinical signs and pathology of giant pacific octopuses in an aquarium setting. between march 2004 and december 2013, there were 19 mortalities: eight males, 10 females, and one individual whose sex was not recorded. average time spent in collection for all octopu ... | 2016 | 27010286 |
| the packaging problem: bivalve prey selection and prey entry techniques of the octopus enteroctopus dofleini. | many predators face a complex step of prey preparation before consumption. octopuses faced with bivalve prey use several techniques to penetrate the shells to gain access to the meat inside. when given prey of mussels mytilus trossulus, manila clams venerupis philippinarum, and littleneck clams protothaca staminea, enteroctopus dofleini solved the problem differently. they pulled apart v. philippinarum and m. trossulus, which had the thinnest shells and the least pulling resistance. p. staminea ... | 2007 | 17696656 |
| phylogenetic relationships among major species of japanese coleoid cephalopods (mollusca: cephalopoda) using three mitochondrial dna sequences. | phylogenetic relationships among 36 species of major coleoid cephalopods from japanese waters were studied using partial sequences of three mitochondrial genes, 16s rdna, 12s rdna, and cytochrome c oxidase subunit i gene. octopoda and decapoda were monophylic groups. within sepioidea, sepiadariidae and sepiolidae were not closely related to sepiidae, but rather related to teuthoidea. sepiidae with a distinct calcareous shell formed a single cluster. myopsida was closely related to oegopsida. wit ... | 2005 | 15738635 |