MICROECOLOGICAL FACTORS IN OYSTER EPIZOOTICS

1961 ◽  
Vol 39 (4) ◽  
pp. 449-485 ◽  
Author(s):  
Marshall Laird
Keyword(s):  
Crassostrea Virginica ◽  
Relevant Literature ◽  
Organic Pollution ◽  
Direct Effects ◽  
Ostrea Edulis ◽  
New Host ◽  
Lethal Temperatures ◽  
Canadian Data ◽  
Dead Animal ◽  
Favorable Conditions

On oyster beds as elsewhere, mud–water interfaces exhibit a biological film harboring saprobic microorganisms. The abundance of these is directly proportional to the amount of decomposing organic matter present. Different communities of protozoa and bacteria characterize each of the levels of organic pollution, which may be defined biologically in terms of a modification of the "Saprobiensystem" of Kolkwitz and Marsson. While the microorganisms concerned are not conspicuous on clean substrata except where especially favorable conditions are afforded certain of them by some dead animal or plant, their general abundance is indicative of pollution. This follows overaccumulation of reducible deposits, initiated by irregular tidal flushing, freshets, and winter icing, and rendering the microenvironment anaerobic. Ostrea edulis and Crassostrea virginica survive temporary exposure to the direct effects of such conditions as well as to near-lethal temperatures, but, weakened thereby, become vulnerable to invasion by saprobes from the enriched biological film. Unless environmental conditions improve before the oysters lose ability to recover, abnormal mortalities will be hastened by the activities of these microorganisms, notably Hexamita inflata (Protozoa). Relevant literature is reviewed, and possible local remedies are discussed. Canadian data are supported by original observations from Wales and Pakistan. Among other new host and locality records, Cristispira balbianii (Spirochaetales) and cercariae of a bucephalid trematode are listed from Ostrea belcheri from Karachi.

An annotated checklist of parasitic lice (Insecta: Phthiraptera) from the Galápagos Islands

Zootaxa ◽  
2013 ◽  
Vol 3627 (1) ◽  
pp. 1-87 ◽  
Author(s):  
RICARDO L. PALMA ◽  
STEWART B. PECK
Keyword(s):  
Native Species ◽  
New Genus ◽  
Relevant Literature ◽  
Valid Species ◽  
New Host ◽  
Taxonomic History ◽  
History Of ◽  
Systematic Relationships ◽  
Host Parasite ◽  
Annotated Checklist

We list all described species and subspecies of parasitic lice from theGalápagos Islands, based on literature and specimen records. A total of eight families, 47 genera, and 104 species and subspecies of parasitic lice are listed, of which 26 are new species records and eight are new genus records. Also, we report 17 new host-louse associations. The checklist includes 17 endemic species (16 from birds, one from a mammal), 79 native species and subspecies (78 from birds, one from a mammal), and eight species and subspecies (five from birds, three from mammals) introduced by human agency. Nine species assigned in error to theGalápagos Islandsin the literature are discussed and deleted from the fauna. For each valid species and subspecies we give information on its taxonomic history, type material, host associations, geographic distribution, biogeographical status, systematic relationships, and relevant literature references. We also give a brief summary of louse biology, and an account of the history of louse collecting, expeditions, collections, and research relating toGalápagos Islandslice. We include a host-parasite list, and a list of hosts which breed in theGalápagos Islandsbut without lice recorded from them. Also, we formally designate four lectotypes from the Kellogg Collection.

Nocardiosis in Mediterranean bivalves: First detection of Nocardia crassostreae in a new host Mytilus galloprovincialis and in Ostrea edulis from the Gulf of Naples (Italy)

2013 ◽  
Vol 114 (3) ◽  
pp. 324-328 ◽  
Author(s):  
Francesca Carella ◽  
Noelia Carrasco ◽  
Karl B. Andree ◽  
Beatriz Lacuesta ◽  
Dolors Furones ◽  
...  
Keyword(s):  
Mytilus Galloprovincialis ◽  
Ostrea Edulis ◽  
New Host ◽  
Gulf Of Naples

Lipids and Fatty Acids of the American (Crassostrea virginica) and European Flat (Ostrea edulis) Oysters from a Common Habitat, and After One Feeding with Dicrateria inornata or Isochrysis galbana

1974 ◽  
Vol 31 (4) ◽  
pp. 403-409 ◽  
Author(s):  
T. Watanabe ◽  
R. G. Ackman
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Crassostrea Virginica ◽  
Isochrysis Galbana ◽  
Ostrea Edulis ◽  
Unicellular Algae ◽  
Unusual Fatty Acids ◽  
Lipid Fractions

The oysters Crassostrea virginica and Ostrea edulis from a common habitat showed species-oriented fatty acid composition patterns for total lipids and lipid fractions. Attempts to modify these patterns by offering the unicellular algae Dicrateria inornata and Isochrysis galbana as food suggest that the oysters rapidly convert qualitatively or quantitatively unusual fatty acids to these species-oriented compositions, although only in the combination of D. inornata and O. edulis was enough fatty acid taken up to modify the oyster fatty acid composition in an easily detectable way. The unusual C22 nonmethylene-interrupted diunsaturated fatty acid components were not found in the O. edulis used for this study.

scholarly journals Towards an Integrative Psychological Model for Climate Change Mitigation Behavior among Managers in the Tourism Industry

2019 ◽  
pp. 120-127
Author(s):  
D. N. Kinyanjui
Keyword(s):  
Climate Change ◽  
Climate Change Mitigation ◽  
Relevant Literature ◽  
Tourism Industry ◽  
Mitigation Measures ◽  
Detailed Knowledge ◽  
Psychological Determinants ◽  
Climate Change Policies ◽  
Favorable Conditions ◽  
Change Mitigation

The aims of the current paper are to provide an extensive review of the theoretical and empirical evidence on which current climate change mitigation efforts are based and to advance a new model of the determinants of mitigation behavior. The study was based on the review of relevant literature. The model specifically demonstrates the interplay between human values, attitude, knowledge, emotions and social norms as determinants of broad and greater levels of mitigation behaviours. The model is complemented by adding age and sex as confounders. It indicates the possible interrelationships between these factors with their joint effects being emphasized. The model addresses a concern that most business-level climate change policies ought to be integrative, but are unfortunately, not. Detailed knowledge of psychological determinants is useful for policy makers to provide favorable conditions in support of business level climate change mitigation measures and how it can be used to measure and compare the impacts of the determinants so as to generate more applicable mitigation measures in  optimizing climate change policies now and in the future.

Patterns in metazoan parasite communities of some oyster species

1999 ◽  
Vol 73 (4) ◽  
pp. 283-288 ◽  
Author(s):  
M.L. Aguirre-Macedo ◽  
C.R. Kennedy
Keyword(s):  
Crassostrea Virginica ◽  
Host Response ◽  
Mite Species ◽  
Principal Factor ◽  
Ostrea Edulis ◽  
Component Community ◽  
Parasite Communities ◽  
Metazoan Parasite ◽  
Oyster Species ◽  
Number Of Individuals

Metazoan parasite communities of Crassostrea gigas and Ostrea edulis from Great Britain, Crassostrea virginica from Mexico, and Saccostrea commercialis from Australia are described and summarized in terms of species composition, species richness, total number of individuals and dominance. Metazoan parasite communities in all host species were composed of turbellarians and the metacercarial stage of digeneans, with the exception of S. commercialis where only metacercariae were found. Arthropods, including one copepod and one mite species, were present only in British oyster species. All metazoan parasite communities of oysters had few species and low density of individuals. Richest communities were found in C. virginica at both component and infracommunity level. The least diverse component community occurred in S. commercialis. Infracommunities in O. edulis and S. commercialis never exceeded one species per host. The host response against parasites is suggested as the principal factor responsible for depauperate parasite communities of oysters. Environmental factors characteristic of tropical latitudes are likely to have enhanced both the number of species and the densities of parasites per host in the infracommunities of C. virginica.

scholarly journals Social Sciences and Inequalities in the New Post-COVID-19 “Normal”

2022 ◽  
Vol 12 (1) ◽  
pp. 1
Author(s):  
Maria José Sá ◽  
Sandro Serpa
Keyword(s):  
Social Sciences ◽  
Social Justice ◽  
Social Cohesion ◽  
Social Inequalities ◽  
Relevant Literature ◽  
Direct Effects ◽  
The Social ◽  
Psychological Educational ◽  
The Relationship ◽  
New Inequalities

The pandemic caused by COVID-19 (either through its direct effects by the disease it causes or the measures taken in an attempt to control its spread) had, and still has, a profound effect at several levels beyond the medical, such as the economic and social, political, scientific, psychological, educational, legal and religious levels, among others. However, studies demonstrate that this influence has not been the same for all due to old inequalities and also the emergence of new inequalities. In this letter to the Editor, the authors discuss some of the contributions of the Social Sciences to the understanding of social inequalities in this new post-COVID-19 “normal” through the mobilization of relevant literature and also their experience in analysing COVID-19 with the eyes of the Social Sciences, notwithstanding their plurality. The results of this analysis allow concluding that the Social Sciences can make a very relevant contribution – in an interdisciplinary way – to the understanding of this phenomenon of the relationship between COVID-19 and inequalities based on socioeconomic factors with the aim of increasing social cohesion and social justice.   Received: 4 October 2021 / Accepted: 11 November 2021 / Published: 3 January 2022

The American species of trematode confused with Bucephalus (Bucephalopsis) haimeanus

Parasitology ◽  
1954 ◽  
Vol 44 (3-4) ◽  
pp. 353-370 ◽  
Author(s):  
Sewell H. Hopkins
Keyword(s):  
Crassostrea Virginica ◽  
Type Species ◽  
Life Cycles ◽  
Ostrea Edulis ◽  
Experimental Proof ◽  
Present Evidence ◽  
Adult Form ◽  
Alligator Gar ◽  
The Family ◽  
Species Characteristics

1. The bucephalid cercaria from Crassostrea virginica (Gmelin), the commercial oyster of the Atlantic and Gulf coasts of North America, has been called Bucephalus haimeanus Lacaze-Duthiers and Bucephalopsis haimeana (Lacaze-Duthiers). Neither of these names is correct. Bucephalus haimeanus Lacaze-Duthiers, 1854, is a parasite of the European oyster, Ostrea edulis L. (and possibly of cockles, Cardium spp.) in oceanic or near-oceanic habitats, while the American species is a parasite of an estuarine oyster and is found almost entirely in the least saline parts of its host's range. The correct name of the American oyster bucephalid is Bucephalus cuculus McCrady, 1874.2. The life cycles of all European marine bucephalids are still unknown. The life cycles described in the European literature are based entirely on morphological resemblances which are not close enough to be convincing, and none of them has been tested by experiment. Bucephalid cercariae do not show any of the features which are used to distinguish genera. So far as present evidence goes, Bucephalopsis haimeana is just as likely to develop into a Rhipidocotyle, a Bucephalus, or a Prosorhynchus as it is to develop into a member of the genus Bucephalopsis Nicoll, 1914, nec Diesing, 1855.3. Bucephalopsis Diesing, 1855, is the name proposed by Diesing for a subgenus created especially for the cercaria Bucephalus haimeanus Lacaze-Duthiers, 1854. Nicoll had no right to use this name for the genus of gasterostomes which, as adults, have a muscular sucker at the anterior end and do not have accessory structures such as a hood or papillae. Up to the present, there is still no evidence that this genus has any connexion with Lacaze-Duthiers's cercaria, other than common membership in the family Bucephalidae. Therefore the new name Bucephaloides Hopkins has been proposed to replace the generic name Bucephalopsis Nicoll, 1914, nec Diesing, 1855, with Bucephaloides gracilescens (Rudolphi, 1819) as the type species. This genus does not include Bucephalus haimeanus Lacaze-Duthiers because the metacercaria and the adult form of that species remain unknown.4. Tennent (1905, 1906, 1909) did not prove that there was any connexion between the oyster cercaria, Bucephalus cuculus McCrady, and the immature bucephalids in Menidia or the adult bucephalids in Strongylura. His drawings show that at least some of the bucephalids which Tennent studied had a hood and therefore belong in Rhipidocotyle. Re-examination of the bucephalids in Strongylura marina reveals that at least three species of bucephalids occur as adults in that host; these are described in this paper as Rhipidocotyle transversale Chandler, 1935, R. lintoni Hopkins, and Bucephaloides strongylurae Hopkins. Rhipidocotyle transversale and Bucephaloides strongylurae were also found in an immature (metacercaria) stage in Menidia, and were the only bucephalids found in Menidia during this study. The excretory systems of the three species in Strongylura all have features which exclude the possibility that they could develop from the oyster cercaria, Bucephalus cuculus.5. Tennent's (1906) drawing (fig. 46) of an adult bucephalid from Strongylura marina, which Eckmann (1932) mentions as the best representation of the species characteristics of Bucephalopsis haimeana (Lacaze-Duthiers), was probably made from a specimen of Rhipidocotyle lintoni.6. Tennent (1909) proved that eggs or larvae from an unknown adult bucephalid in Lepisosteus osseus could infect oysters, Crassostrea virginica, and develop into sporocysts which would grow in oysters for at least one month. This is the only experimental proof of a connexion between an adult bucephalid in a fish and a larval bucephalid in an oyster. Until the present, no bucephalid from a gar (Lepisosteus) had ever been described. In the present paper Rhipidocotyle lepis-ostei Hopkins is described from adults in Lepisosteus spatula, the alligator gar, in Louisiana. The metacercariae of Rhipidocotyle lepisostei are abundant in the fin rays of mullets, Mugil cephalus and M. curema. The excretory system of this species is not identical with that of Bucephalus cuculus, but is not so different as to exclude the possibility that the oyster cercaria might develop into R. lepisostei. If, in the future, R. lepisostei is proved to be the adult form of Bucephalus cuculus, the name of the species will become Rhipidocotyle cuculus (McCrady), and R. lepisostei will become a synonym.

scholarly journals Α New Host Plant for Scobicia cheνrieri (Villa) (Coleoptera: Bostrychidae)

2017 ◽  
Vol 9 ◽  
pp. 73
Author(s):  
C.TH. Buchelos
Keyword(s):  
Relevant Literature ◽  
The Philippines ◽  
Mediterranean Coast ◽  
Quercus Coccifera ◽  
New Host ◽  
English Oak ◽  
Evergreen Oak ◽  
The Tropics ◽  
First Time ◽  
Wood Boring

Bostrychidae is primarily a family of wood-boring beetles, distributed mainly in the tropics and subtropics. Many species are serious pests of growing trees and felled timber. One species, Rhysopertha dominica (F.), is a grain borer and the most frequently met among beetles infesting stored wheat in Greece (Buchelos 1981). Two other bostrychids, Dinoderus minutia (F.) and Dinoderus brevis Horn, have been recently found in Greece infesting bamboo articles imported from Hong-Kong and the Philippines respectively. Wooden parts (branches of 3 to 18 cm in diameter) of Brachychiton acerifolium Mull. and Brachychiton diversifolium G. Don. (Sterculiaceae) trees, widely used as ornamentals in alleys and parks in Attika, Greece, that have been cut and stored for one at least year in the open, were found heavily infested by bostrychid bee­tles and their larvae; the exterior of these branches was densely perforated by tunnel openings about 1,5 mm in diameter, while the interior presented an almost complete deterioration due to numerous galleries caused by the insects. Due to the fact that the living Brachychiton trees of the region examined were found infestation free, one is lead to the conclusion that the infestation occurred after felling; furthermore, the infestation on B. acerifolium seemed more severe than on B. diversifolium wooden parts. The identification of the adults, based on taxonomic keys of Lesne 1900, Renter 1911, Por to 1929, Portevin 1931 and Fisher 1950, lead to Scobicia chevrieri (Villa) and was confirmed by the identification group of the Bayerische Staatsamlung, Munich. The species belongs to the subfamily Bostrychinae, tribe Xyloperthini, genus Scobicia Lesne; it has also been found under the synonyms: Apate chevrieri Villa, Apate capilata Dejean, Xylopertha chevrieri J. Duval, Xylopertha foveicollis Allard, Xylopertha pustulate Kiesenwetter and Scobicia pustulate Jacobson. The adults found in the region of Attika, near Athens, are 3.3-4.5 mm long and 1.2 to 1.5 wide. S. chevrieri is reported being distributed in many regions of Italy from the Alpes and Tyrol to Sardinia and Sicily, across the French Mediterranean coast and Corsica, Spain (Malaga, Seville, Cordoba), Morocco, Tunisia, Algeria, Israel, Libanon, Syria, Caucasus, Crimea and Cyprus. In the relevant literature, S. chevrieri is recorded attacking mainly dead branches of the following plants: fig (Ficus sp.), mulberry (Maras sp.), green oak (Quercus ilex L.), English oak (Quercus robur L.), evergreen oak (Quercus coccifera L.), laurel (Laurus nobilis L.), mastic-tree (Pistacia lentiscus L.), birch (Betula sp.), fox grape (Nibs lahrusca L.), pomegranate (Punica granatani), chestnut (Castanea sp.) and gem-tree (Eucalyptus spp.). Brachychiton spp. is recorded here for the first time as host of the insect.

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