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1.
M. Zimmer J. Danko S. Pennings A. Danford T. Carefoot A. Ziegler R. Uglow 《Marine Biology》2002,140(6):1207-1213
In order to test three hypotheses on digestive constraints that may have affected the colonization of land by isopods, two marine isopods and one semi-terrestrial species were screened for their ability to oxidize phenolic compounds and digest cellulose in natural and artificial diets. Ligia pallasii (Isopoda: Oniscidea) and Gnorimosphaeroma oregonense (Isopoda: Sphaeromatidea) oxidized dietary phenolics, but Idotea wosnesenskii (Isopoda: Valvifera) did not, even though it feeds on seaweeds that are rich in phenolics. All three species were able to digest some cellulose, but this ability was least developed in the marine phytophagous species, Idotea wosnesenskii, and best developed in the semi-terrestrial L. pallasii. After reducing the number of endosymbiotic bacteria in the hepatopancreas (midgut digestive gland) by feeding antibiotics, cellulose digestion in L. pallasii was significantly reduced. Our results are consistent with the hypotheses that (1) the ability to oxidize phenolics is absent in phytophagous marine isopods, but present in saprophagous marine and semi-terrestrial species, (2) the ability to digest cellulose was an important pre-adaptation facilitating a fully terrestrial life-style in isopods, and (3) endosymbiotic bacteria in the hepatopancreas aid digestion in terrestrial isopods, and to a lesser degree in semi-terrestrial species, but not in marine isopods. 相似文献
2.
The chemoautotrophic potential of the two co-occurring larger and smaller bacterial endosymbionts of the gutless marine oligochaete
Inanidrilus leukodermatus was determined using immunocytochemistry. An antibody directed against the Form I of ribulose-1,5-bisphosphate carboxylase/oxygenase
(RubisCO), the key CO2-fixing enzyme of the Calvin–Benson cycle, consistently labeled the larger symbionts. Electron microscopic spectroscopy showed
that the larger symbionts contained sulfur in intracellular globules and to a lesser degree in the cytoplasm. The presence
of RubisCO and sulfur indicates that the larger endosymbionts of I. leukodermatus are chemoautotrophic sulfur-oxidizing bacteria. In contrast, no RubisCO or sulfur was detected in the smaller endosymbionts
of this host.
Received: 28 September 1999 / Accepted: 29 May 2000 相似文献
3.
A. Clarke 《Marine Biology》1979,52(2):157-160
When fed shrimp every 2 days, the isopod Glyptonotus antarcticus Eights assimilated over 90% of the ingested food. Errors in this estimate due to loss of food material during maceration by G. antarcticus were investigated and allowed for. These results are discussed in relation to data for other isopods and marine invertebrates. 相似文献
4.
There are many reported associations between mussels and other invertebrates, such as pea crabs, polychaetes, turbellarians
and copepods, which live in their mantle cavities. The boundary between commensalism and parasitism is often indistinguishable
because of insufficient knowledge or because the interaction is variable. Preliminary evidence led to a closer examination
of the relationship between the mussel, Mytilus edulis platensis, and an isopod, Edotia doellojuradoi, previously described as commensalism. Monthly intertidal samples of mussels were taken from September 2004 to August 2005
at Caleta Cordova Norte (45°43′S, 67°22′W) in southern Argentina and assessed for the prevalence and abundance levels of isopods.
Mussels with and without isopods were measured, examined for evidence of gill damage and their condition (soft tissue dry
weight) was determined. The overall isopod prevalence in mussels was 57.9% and infestation varied with mussel length, with
maximum occurence at 30.2 mm (medium-sized mussels). Experimental evidence indicated that the position of the isopod inside
the mussel depended on the feeding activity of the mussel. Female isopods were observed grasping the ventral food groove of
the gill demibranchs and feeding on the mucous food strand produced by the mussel. Juveniles and males were observed clustered
together on the dorsal side of the single female in each occupied mussel, suggesting extended maternal care. Gill damage was
observed in 58.2% of mussels at the Argentine site and was significantly associated with isopod occurrence. Categorical regression
analysis showed that the most important factor associated with the degree of gill lesions was the number of male and juvenile
isopods per mussel, followed by the length of female isopods and the developmental stage of juveniles. Conversely, the degree
of gill damage decreased with increasing mussel length. Overall, E. doellojuradoi had a significant effect on mussel condition throughout the year, with low flesh weight in mussels with isopods, except during
the austral summer and early autumn. In contrast to previous studies, which concluded that the isopod was a commensal, the
present study clearly demonstrates that E. doellojuradoi is a parasite of M. edulis platensis. Other symbiotic interactions formerly classified as commensal might not be innocuous on further investigation, especially
if samples are taken at multiple sites and at different times of the year. 相似文献
5.
Feeding,food preference,and the uptake of food energy by the supralittoral isopod Ligia pallasii 总被引:3,自引:0,他引:3
T. H. Carefoot 《Marine Biology》1973,18(3):228-236
Analyses of gut contents of freshly collected Ligia pallasii (Brandt) showed that the principal foods were encrusting diatoms, insect larvae, occasional members of the same species, and a variety of red and green seaweeds growing in the upper interiidal tidepool habitat. L. pallasii prefers to eat the green seaweed Ulva sp., and the brown alga Nereocystis luetkeana, when given a choice between several seaweeds, although neither of these forms is normally accessible to the isopods. The absorption (assimilation) of food-energy was 78% on a diet of Ulva and 55 to 76% on a diet of N. luetkeana—representative values for an algivorous invertebrate. A correlation analysis on the relationship of feeding preference of L. pallasii with calorific value of 7 potential seaweed foods suggested that feeding preference in this species is related to factors other than energy content of the food. Food preferences of invertebrates are discussed in relation to calorific value, accessibility, and to various nutritional factors. 相似文献
6.
In recent years the pace of exotic species introduction and invasion has accelerated, particularly in estuaries and wetlands.
Species invasions may affect coastal ecosystems in many ways. Alteration of sedimentary environments, through structure formation
and burrowing, has particularly dramatic effects on coastal habitats. This study examines modification of channel bank and
marsh edge habitat by the burrowing Australasian isopod Sphaeroma quoyanum Milne Edwards, in created and natural salt marshes of San Diego Bay and San Francisco Bay. Abundance and distribution patterns
of this isopod species, its relationships with habitat characteristics, and its effects on sediment properties and bank erosion
were examined seasonally, and in several marsh microhabitats. Mean isopod densities were 1541 and 2936 individuals per 0.25 m2 in San Francisco Bay, and 361 and 1153 individuals per 0.25 m2 in San Diego Bay study sites during December and July 1998, respectively. This isopod forms dense, anastomosing burrow networks.
S. quoyanum densities did not differ as a function of location within creeks or location in natural versus created marshes. Burrows,
which are on average 6 mm wide and 2 cm long, were associated with firm sediments containing high detrital biomass. Although
erosion is a natural process along salt marsh banks, enclosure experiments demonstrated that isopod activities can enhance
sediment loss from banks. In areas infested with S. quoyanum, losses may exceed 100 cm of marsh edge per year. The effects of habitat alteration by this invading species are likely to
increase in severity in the coastal zone as these ecosystems become degraded.
Received: 30 March 2000 / Accepted: 21 September 2000 相似文献
7.
In south-western Australia, the isopod Limnoria agrostisa commonly burrows into leaf clusters and immature shoots of Amphibolis griffithii. The isopod also burrows into the sheath and rhizomes of Posidonia species. In A. griffithii, the isopod consumes new tissue within the sheath, damaging or destroying the meristem. This results in malformation of new
leaves or destruction of whole leaf clusters with the potential to reduce the photosynthetic area of a shoot. The isopod has
been found in all but one meadow of A. griffithii examined over 1,000 km of the Western Australian coastline. It was present throughout the year and showed little variation
in abundance. Young were produced year round, but were more abundant in the summer months. Females, 3.5 mm in length or larger,
produced 2–5 young that were brooded within the leaf cluster or base of an immature shoot. Within a meadow, 40–70% of shoots
and 10–20% of leaf clusters were damaged by isopods. Seasonal trends were not consistent, but damage appeared to be higher
in summer when isopod abundance was higher. Approximately 40% of clusters were destroyed by isopod damage. Isopods attack
shoots of all ages, but damage was often located on apical clusters. There was no evidence that isopod damage initiated branching
or leaf cluster formation. Estimations of clusters damaged or destroyed may be conservative, as only those clusters remaining
on a shoot could be counted, and cluster loss could not be quantified. Examination of defoliated stems on upright shoots and
horizontal rhizomes indicated that many were destroyed by isopods. The effect of L. agrostisa although substantial appears to be a feature of healthy seagrasses throughout southern Australia. 相似文献
8.
Electron microscopic examination of thin-sectioned Limnoria tripunctata from creosoted and untreated wood substrates from Panama, Florida, and laboratory aquaria, coupled with limnorian behavioral studies revealed that bacteria may contribute to the wood boring, nutrition, and creosote-resistance of these isopods. Ingested along with wood fragments and encased in a peritrophic membrane in the isopod intestine, these bacteria, upon lysis, may provide supplemental nutrition to the nitrogen-poor wood diet of L. tripunctata. Ingested material has never been observed in the digestive diverticula of limnorians and the presence of the peritrophic membrane in the isopod intestine has been correlated with feeding. Isopods from creosoted wood differed from those inhabiting untreated wood in that the former contained relatively larger and more diverse bacterial populations both on their exoskeletons and in their gut contents. These isopods harbored bacteria, which apparently bypassed the peritrophic membrane and lived in association with the isopod intestinal lining. These gut-associated bacteria were lost when laboratory isopods reared on creosoted wood were transferred to untreated wood. Laboratory isopods reared solely on creosoted or untreated wood were exposed to creosoted and untreated wood substrates, both sterilized and unsterilized. Boring and mortality data from these studies indicated that the creosote-reared population had a microbial flora whose activity facilitated isopod colonization of creosoted substrates. We present the hypothesis that creosote hydrocarbons provide nutrition for isopod-associated bacterial populations and that L. tripunctata may benefit from a concomitant bacterial detoxification of the creosote. 相似文献
9.
Complexity in the relationship between matrix composition and inter-patch distance in fragmented habitats 总被引:1,自引:1,他引:0
The connectivity of fragmented landscapes is a function of the physical distance between suitable habitats and the characteristics
of the habitat through which the animal is moving, i.e. the matrix. Experimental manipulations done to explain how spatial
arrangement and composition of habitats affects biota remain scarce, particularly in marine systems. Holdfasts of the common
kelp, Ecklonia radiata, are discrete units of habitat for small invertebrates (e.g. amphipods, isopods, molluscs, annelids) that can be isolated
from other holdfasts by habitat, which may be less suitable (e.g. other species of algae or relatively bare space). We compared
assemblages, which colonised defaunated holdfasts in experimentally created small-scale landscapes where patches of habitat
(holdfasts) were distant versus close together and which had Sargassum spp. versus relatively bare space in the matrix. We also compared colonisation across matrices of crushed fucoid algae to
assess whether the structural or chemical nature of algae in the matrix had the most influence on the colonisation. Assemblages
in defaunted holdfasts differed between those that were close to and those that were distant from undisturbed holdfasts, where
the matrix was devoid of vegetation. Where Sargassum spp. was present in the matrix, however, this difference disappeared and was possibly due to the chemical, rather than structural,
characteristics of the fucoid matrix. The extent to which matrix habitat is a barrier to movement of invertebrates among holdfasts
thus depends on not only how extensive it is but what type of habitat it contains. As within terrestrial systems, the nature
of the matrix is also likely to be a fundamental component of the connectivity within marine systems. 相似文献
10.
I. D. Marsden 《Marine Biology》1973,21(2):75-85
The survival of the salt-marsh isopod Sphaeroma rugicauda (Leach) was investigated under varying conditions of salinity and temperature following thermal acclimation. It was found that the isopods showed increased resistance to high temperatures following warm-acclimation, and that this increase was greater in adults than in juveniles. S. rugicauda were able to withstand salinity changes event at high experimental temperatures, although this was more pronounced in the older individuals. Behavioural responses in a temperature gradient showed that the isopods could avoid potentially lethal temperatures. 相似文献
11.
Kendall D. Clements Isabel B. Y. Pasch Damian Moran Susan J. Turner 《Marine Biology》2007,150(6):1431-1440
Bacterial diversity in the microbial communities of posterior gut sections of three temperate marine herbivorous fish species
from New Zealand was characterised using Amplified Ribosomal DNA Restriction Analysis, and 16S rRNA gene amplification and
sequencing methods. The fish were collected in 1999–2000 in the Hauraki Gulf, New Zealand (35°54’–36°24’S, 174°48’–175°25’E).
The gastrointestinal bacterial communities of Kyphosus sydneyanus (Günther, 1886) (F. Kyphosidae), Odax pullus (Forster in Bloch and Schneider, 1801) (F. Labridae) and Aplodactylus arctidens Richardson, 1839 (F. Aplodactylidae) were dominated by five clades of bacteria, four of which belong to recognized clostridial
clusters. The clone libraries of K. sydneyanus and O. pullus contained sequences from most of these clades, but were dominated by members of clostridial clusters XI and XIVa, respectively.
The clone library of A. arctidens was dominated by members of clostridial cluster XIVb and an unassigned cluster containing Eubacterium desmolans and Papillibacter cinnaminovorans. The finding that strains of Firmicutes dominated the gastrointestinal microbial communities of all three fish species is consistent with the results of similar
studies on terrestrial vertebrate herbivores. This work thus contributes to the view that gastrointestinal symbionts in some
marine herbivorous fishes may play a similar role to those in terrestrial vertebrate herbivores studied to date. 相似文献
12.
During submersible surveys along the continental slope (summers of 1991 and 1992, 184–847 m) between False Cape, Virginia,
and Cape Hatteras, North Carolina, USA, we observed the aegid isopod, Syscenus infelix Harger, attached to the macrourid Nezumia bairdii (Goode and Bean). This is the first report of S. infelix attached to fishes in the western North Atlantic. The association of this blind isopod with its host appears species specific.
The large, conspicuous isopod always attached to a fish in the same location, the dorsal midline, immediately behind the first
dorsal fin. Attachment appears to be long term, with the isopod forming a characteristic scar consisting of a distinct discolored
oval depression with seven small, dark impressions that coalesce as the fish grows. Only one S. infelix was found on each host fish. The isopod occurred on 23.7% of N. bairdii observed from submersible on the middle continental slope off Virginia and North Carolina, compared with 16.6% of 1236 museum
specimens of the same species (based on inspection for scars) collected at latitudes 26°–64°N. Prevalence of the fish–isopod
association was not correlated with depth or latitude. We also found identical scars on preserved specimens of N. aequalis (2.6% of 660 specimens), N. sclerorhynchus (1.2% of 86 specimens), and N. suilla (14.3% of 7 specimens), mostly from areas outside the range of N. bairdii. No scars were found on museum specimens of N. atlantica (n=27), N. cyrano (n=57), or N. longebarbata (n=7). The low incidence of isopod attachment on these species suggests that N. bairdii is the preferred host. Infestation by the isopod appears to result in erosion of host fish scales and tissue. We propose
that S. infelix is an obligate associate of its host fish and should be considered parasitic.
Received: 9 June 2000 / Accepted: 21 October 2000 相似文献
13.
Biogeographic and phylogenetic data on the deep-sea isopod family Ilyarachnidae (Paraselloidea) document its origin and evolutionary radiation in the deep sea. The distribution of eyes among paraselloidean families suggests an in situ evolution for all those families which have primarily deep-sea distributions. Present-day distributions of paraselloidean isopods provide no hints to their ultimate sources in shallow water. These findings contrast to recent suggestions in the literature that the deep-sea isopod fauna has been derived from shallow Antarctic waters. 相似文献
14.
Gnathiid isopods are one of the most abundant groups of ectoparasites on coral reef fishes. They, and other isopods, have
been shown to significantly affect the health and behaviour of many reef fish. Whether isopod emergence differs among habitats
on coral reefs is not known. In this study, we measured emergence rates of parasitic isopods (Gnathiidea and Flabellifera)
in six habitats at two sites at Lizard Island during new moon periods in March and December 2004. Isopods were collected from
the periphery and centres of micro-reefs, patch reefs, continuous reefs, and from inter-reefal habitats (sand or rubble) with
1 m2 emergence traps. Sites (Casuarina and Coconut Beach) were located on opposite sides of Lizard Island. Live gnathiids were
collected with light traps in November 2005 to investigate species differences between sites. At both sites, the most abundant
gnathiid species was exclusive to that site. More gnathiid larvae emerged at night, and emergence of fed gnathiids (pranizae)
and flabelliferan isopods was almost exclusively nocturnal. Diurnal emergence was greater at Coconut Beach than Casuarina
Beach. Although emergence counts were not consistently affected by parameters such as habitat, site, or sampling period, gnathiid
size and feeding state were. Where significant differences existed, gnathiids were larger and more often fed over reef borders
than centrally. We suggest first stage larvae (Z1) have the largest influence on total abundance and are patchily distributed
in accordance with adults from which they have recently hatched. As later stage larvae depend on fish, more successful (fed)
and older larvae are found on the edges of reefs where appropriate hosts may be more abundant, or predation is lower. Gnathiids
were over-dispersed in all habitats investigated, including apparently homogeneous beds of coral rubble and sand. This indicates
that their distributions may be better predicted by very fine scale differences in substrate or that aggregations are the
result of gregariousness and may be difficult to predict on the basis of substrate. Emergence traps collected comparatively
few parasitic flabelliferan isopods. This community differed greatly from the previously described community of scavenging
isopods at Lizard Island. These differences are probably the result of differences in trapping methodology. 相似文献
15.
Four species of isopod characteristic of salt marsh habitats, Tylos ponticus, Porcellio lamellatus, Halophiloscia couchii and Armadillidium album coexist in the upper reaches of the Ria Formosa lagoon salt marsh system in southern Portugal. In this locality, T. ponticus is the most abundant of the four species with mean annual densities of 2,950 m−2 and a peak density of 10,387 m−2 in July 1998 which is very much higher than what has previously been recorded for any isopod in any habitat. The mean annual
densities for the other species were lower: P. lamellatus 36 m−2, A. album 19 m−2 and H. couchii 3 m−2, indicating a less significant role in this ecosystem. Tylos ponticus and A. album started to breed on May, 24 and 12 months after release from the marsupium, respectively, where as other species start to
breed in March, 12 months after their release from the marsupium. Tylos ponticus has a relative growth rate (RGR) of 0.23 between release from the marsupium and time of first breeding in July of its second
year and breeds at a mature mass of 3.6 mg AFDM whereas the other three species mature after 10–12 months, have more than
double this RGR but because of the shorter pre-reproductive period breed at masses of 1.8 mg AFDM for P. lamellatus, 1.0 mg AFDM for H. couchii, and 1.1 mg AFDM for A. album, respectively. The mass specific fecundity of all three of the less abundant species was higher than that of T. ponticus but the offspring of T. ponticus were ten times heavier than those of the next largest species, P. lammellatus. The difference in abundances between the species is interpreted as being due to the larger mass of the offspring of the
most successful species. This larger mass confers an adaptive advantage due to larger size being associated with reduced juvenile
mortality for isopods under abiotically stressful conditions.
M. Sprung died in an accident on June 18, 2003 相似文献
16.
A total of 38 219 specimens representing 63 species of marine isopods (Crustacea) from deep and shallow Arctic waters were studied in a search for epizoic foraminifers (Protozoa). Foraminifers occurred on 21 species, and their frequency was generally low. A total of 290 foraminifer individuals were found, of which 289 belonged to Cibicides wuellerstorfi, C. refulgens and Cibicides spp. (juveniles) (Cibicidae), while only a single individual belonged to Cornuspira sp. (Cornuspiridae). The foraminifers were most frequent on species of the families Munnidae, Ischnomesidae (suborder Asellota) and on Gnathia stygia (suborder Gnathiidea), but were totally absent from the asellote families Janiridae, Haploniscidae, Nannoniscidae and from the suborder Epicaridea. The foraminifers were mainly located on the legs (Munna acanthifera), the anterior part of the body (Haplomesus quadrispinosus, heteromesus frigidus), or on the head (G. stygia adults). The epizoic foraminifers occur mainly on epibenthic isopods, which do not or only rarely clean themselves. The foraminifers are known to prefer elevated substrata, and in this the habitat of the isopods and the foraminifers coincide. The size of individual isopods was not related to the presence or absence of foraminifers. 相似文献
17.
Population dynamics and reproductive biology of the commensal isopod Colidotea rostrata (Crustacea: Isopoda: Idoteidae) 总被引:2,自引:0,他引:2
T. D. Stebbins 《Marine Biology》1989,101(3):329-337
Colidotea rostrata (Benedict, 1898) is the only known commensal idoteid isopod, living on and mimicking the color of two northeastern Pacific sea urchins of the genus Strongylocentrotus. The population dynamics and reproductive biology of C. rostrata on its host urchins were studied at a low rocky intertidal area in southern California (33°40N; 118°30W) from December 1984 to December 1986. Isopod populations remained relatively stable throughout the 2 yr study, with isopods inhabiting an average of 56.1% of the urchins at 6.1±0.6 (x±2 SE) isopods per urchin. Female isopods reach sexual maturity at a length of 6.8 mm. Fecundity in C. rostrata averaged 11.8±0.9 (x±2 SE) embryos per brood, and increased with female body size. Breeding occurs all year long in C. rostrata, with a main reproductive period between the warmer spring and summer months. Newly released mancas and juvenile isopods were present during all months of the study. C. rostrata differs from the free-living Idoteidae in its smaller maximum size, reduced fecundity, 1:1 sex ratio, and low juvenile mortality. These features may represent adaptations to a commensal life style that reflect a reduced mortality pressure on these isopods. 相似文献
18.
F. Maltagliati A. P. Peru M. Casu F. Rossi C. Lardicci M. Curini-Galletti A. Castelli 《Marine Biology》2000,136(5):871-879
The genetic relationships between morphologically indistinguishable marine and brackish populations of Syllis gracilis Grube, 1840 (Polychaeta: Syllidae) were studied by means of allozyme electrophoresis. Samples of S. gracilis from marine coastal and brackish-water habitats were examined for variation at 13 presumptive loci. In addition, a sample
of the closely related species S. prolifera (Krohn, 1852) was analysed. Five loci were multiallelic in at least one population of S. gracilis and eight loci in S. prolifera. Low to moderate levels of within-population genetic variability were found, with average expected heterozygosity values
ranging from H = 0.068 (±0.043 SE) to 0.187 (±0.069 SE) in the populations of S. gracilis; higher values were found in S. prolifera (H = 0.325 ± 0.076). The presence of various private alleles indicated a marked genetic divergence among populations of S. gracilis, with Nei's genetic distances ranging from D = 0.000 to 0.833 and a highly significant F
ST value. Furthermore, evidence for strong genetic heterogeneity between two sympatric marine populations was found. UPGMA cluster
analysis and multidimensional scaling pointed out a clear genetic divergence between brackish and marine populations. At least
two genetically divergent entities occurred in marine and brackish habitats. This could be due to local adaptation of individuals
coming from marine populations to brackish habitats, but more presumably to the occurrence of a species complex within S. gracilis.
Received: 6 June 1999 / Accepted: 7 February 2000 相似文献
19.
The ghost shrimp Neotrypaea californiensis is imported into southern California from Oregon and Washington for use as live bait in recreational marine fisheries. We
studied the population genetic structure of N. californiensis across much its range to assess the possibility that the transport of ghost shrimp across phylogeographic boundaries poses
a risk of homogenizing existing genetic variation in the species. Analyses of two mitochondrial DNA markers showed little
phylogeographic structure across the sampled range, suggesting that this risk is low. Unexpectedly, mitochondrial DNA analyses
revealed that a second putative species of ghost shrimp frequently coexisted with N. californiensis in southern California intertidal habitats; almost all previous studies of soft-sediment communities in the region report
the presence of N. californiensis only. We also assessed the possibility that the import of ghost shrimp might pose a risk of introduction of a parasitic castrator,
the bopyrid isopod Ione cornuta, into southern California waters, where it does not appear to be native. Prevalence of living I. cornuta in samples purchased from bait shops was high (5.8%), suggesting that this is a real risk that merits further study. 相似文献
20.
E. Sparrevik 《Marine Biology》1999,133(3):437-441
Laboratory experiments were performed to investigate the effects of sediment texture and presence of non-moulting conspecifics
on size-specific moulting survival of the omnivorous benthic isopod Saduria entomon (L.). The moult survival of S. entomon was significantly higher in coarse sand than in very soft muddy clay sediment. However, there was no size-related difference
in moult survival between the substrates. Due to cannibalism, moult survival of S. entomon was substantially reduced in the presence of non-moulting conspecifics. Moult survival was higher when the moulter was larger
than the non-moulters compared to when the moulter was smaller. In contrast, the absolute size of the moulter or the non-moulters
did not affect moult survival. The sex of the moulting or non-moulting isopods had no effect on the survival of the moulters.
Based on the results from laboratory experiments, sediment texture and cannibalism are suggested to affect survival during
moult of S. entomon in the field.
Received: 12 February 1998 / Accepted: 14 November 1998 相似文献