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571.
On the basis of 658 specimens collected over an 11 year period, the symbiotic eunicid polychaete, Iphitime paguri Fage & Legendre, 1934, is redescribed, and its biology in its presumed preferred host, Pagurus prideaux Leach, 1815, is outlined. The main ecological part is based on sampling of Pagurus on five occasions throughout a year in Raunefjorden, southwest of Bergen. Iphitime paguri turned out to have a strong sexual dimorphism, both in outer appearance and in the morphology of the jaws. Both juveniles and mature individuals of both genders are described. The infestation rate of Pagurus prideaux was very high (as opposed to the low reported infestation rate in Pagurus bernhardus, generally regarded as the host of this species) and the symbiotic polychaetes turned out to have a distinct pattern of host utilization in different life stages. Ripe males and females were, at certain times of the year, generally found more or less intertwined in the apex of the gastropod shell inhabited by its host. Small larval stages were found in the same place. Intermediate size groups were found in the gill chamber and in a sulcus on the carapax of the pagurid host. 相似文献
572.
Salka Ndazo Minka Joseph Olusegun Ayo 《Journal of applied animal welfare science : JAAWS》2013,16(3):272-288
This study investigated the effects of 12 hr of road transportation during the hot-dry conditions and the modulating role of ascorbic acid (AA) on the hydration state of goats. Twenty goats who served as treatment goats received oral administration of 100 mg/kg body weight of AA, whereas another 20 control goats received sterile water; thereafter, the goats were loaded and transported. The study determined changes in skin thickness; albumin (Alb); total protein (TP); elimination of the gut content; fecal water; urine specific gravity (SG); and pH before, during, and after the transportation. The result obtained in the control goats showed significant (p < .05) increases in the values of TP, Alb, urine SG, and pH; elimination; and drinking behavior, whereas skin thickness decreased over transportation. In the treatment goats who were administered AA, the changes observed in the values were insignificant (p > .05). In conclusion, 12-hr road transportation of goats induced dehydration, which may affect the welfare and health status of the goats. The administration of AA ameliorated the risk of adverse effects of handling, loading, transportation, and hot-dry conditions on hydration state of goats. 相似文献
573.
Observations on the diagenesis of the Lower Triassic Sudair Formation,Abu Dhabi,United Arab Emirates
Summary The Lower Triassic Sudair Formation in the United Arab Emirates (U.A.E.) ranges in thickness from 178–297 m and comprises
three units consisting of interbedded limestone, argillaceous limestone, dolomite and anhydrite. The Lower Unit contains variable
energy shallow marine, slightly argillaceous mudstones and subordinate ooliticpeloidal packstones and grainstones with minor
dolomite and anhdrite. The Middle Unit consists of argillaceous and ferroan dolomite deposited in a lagoonal to supratidal
setting. The Upper Unit comprises argillaceous mudstones and dolomites at the base grading upward into argillaceous anhydrite
deposited in a restricted shallow marine to sabkha setting. These units represent the transition from a carbonate/evaporite
shelf with significant terrestrial input to an evaporitic platform defined by an overall shallowing-upward sequence.
Diagenesis in the Sudair includes extensive leaching of grain-supported carbonates, partial to complete dolomitization, evaportie
formation, clay nucleation, fracturing/pressure solution, late cementation by coarse calcite spar and saddle dolomite, and
hematite formation. These processes have had the cumulative effect of reducing the secondary porosity. Dolomitization occurred
in two stages: an earlier progression of rhombic-sucrosic-aphanocrystalline dolomite, and a later coarse crystalline and saddle
dolomite fracture fill. 相似文献
574.
Victor M. Tuset Ralph Imondi Guillermo Aguado José L. Otero‐Ferrer Linda Santschi Antoni Lombarte Milton Love 《Journal of morphology》2015,276(4):458-469
Sagitta otolith shape was analysed in twenty sympatric rockfishes off the southern California coast (Northeastern Pacific). The variation in shape was quantified using canonical variate analysis based on fifth wavelet function decomposition of otolith contour. We selected wavelets because this representation allow the identifications of zones or single morphological points along the contour. The entire otoliths along with four subsections (anterior, ventral, posterodorsal, and anterodorsal) with morphological meaning were examined. Multivariate analyses (MANOVA) showed significant differences in the contours of whole otolith morphology and corresponding subsection among rockfishes. Four patterns were found: fusiform, oblong, and two types of elliptic. A redundancy analysis indicated that anterior and anterodorsal subsections contribute most to define the entire otolith shape. Complementarily, the eco‐morphological study indicated that the depth distribution and strategies for capture prey were correlated to otolith shape, especially with the anterodorsal zone. J. Morphol. 276:458–469, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
575.
A population ofSchisandra glabra (Schisandraceae) found in the cloud forest of northeastern Hidaglo state, Mexico, represents a new family for the Mexican flora and the first record for the species outside of the southeastern United States. Morphological comparisons of foliar and floral characteristics of this population with southeastern U.S. specimens reveal the material in both countries to be similar in morphology and apparently conspecific.Schisandra glabra is the only species of the family on the American continent. We speculate that the disjunct distribution of the Mexican population is the result of the gradual contraction of an otherwise wider distribution in connection with climatological changes associated with the Tertiary. The species is described and illustrated to familiarize students interested in the Mexican flora with the species and family. 相似文献