摘要:

In an age of specialization it comes almost as a surprise to find that a symposium honouring the scientific contributions of one man should bear such a broad title: the Biology of Marine Invertebrates. Wyn Knight‐Jones has his specialization, as the long series of papers on the ecology and taxonomy of Spirorbidae reveals; but the earlier papers, offering new leads into several diverse facets of marine ecology, appealed to and stimulated many young biologists. Several of these here present some of their own recent research, which either sprang directly or indirectly from Wyn's own work or guidance to them as graduate students or is offered by colleagues in respect of friendship over many year

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01966.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Protoleodorais redefined to accommodate three North Pacific Pileolariinae, which characteristically have a soft‐walled brood pouch with a lobe extending from the operculum into the faccal groove.Protoleodora uschakovisp. nov. is close toP. coronataand even closer toP. asperata (=‘Spirorbis medius’). BushiellaandJugariaare related circumarctic genera, but these lack proximal extensions to their brood pouches. All genera which brood in the operculum are surveyed briefly and new names are proposed for some which are preoccupied, reinstatingNeodexiospiraand replacingAmplaria, Duplicaria, Nidularia, SimplicariaandSinist

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01967.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Brood chambers of Januinae are cuticular and have to be shed to liberate the larvae, whereas those ofPileolariaare bounded by two epithelia and are used repeatedly. Links for interpreting these differences are to be found amongst some of the smaller genera ofPileolariinae.InAmplicariaandVineariathe embryos are held between a pair of opercular plates, which form distal and proximal cups with the concavities facing each other. They are successive units in a series of sheddings and renewals, found generally in Spirorbidae even on non‐brooding opercula. AJanuabrood chamber corresponds with the distal component of such a pair, the proximal component being represented by the basal plate. In most Pileolariinae the brood chamber is formed entirely by the proximal component. AmongstNidificariaspecies, some hold the embryos in a simple cup with no distal protection, but others have the aboral side of the cup extended and growing over distally, like the dorsal lip of a blastopore. The aperture that remains may be almost closed but can open again to liberate the larvae. Brood chambers ofPileolariaare exactly like that, except that they lack any calcification proximally. Those ofJugariaandBushiellaare similar, but with additional protection through retention of distal plates.Protoleodoraspecies are subarctic and very close toJugariaandBushiellain distribution and morphology, but they have less calcification, readily lose their distal plates, and develop soft‐walled brood pouch extensions which can accommodate very large broods. There seem to be tenuous links between the Pileolariinae and the Romanchellinae, southern hemisphere spirorbids which incubate in their tubes. Fertilization and spawning need further st

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01968.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Thirty‐two species of calcareous tube‐dwelling polychaetes (Families Serpulidae and Spirorbidae) are recorded from coral reefs in the Sudanese Red Sea. Twenty‐two species belong to the family Serpulidae, and 10 to the family Spirorbidae. Brief descriptions and illustrations of tubes and opercula are included. Factors affecting settlement, post‐settlement survival, and the ecological distribution of these species are discussed. Grazing by fish and echinoids results in the removal of many larvae and young tube worms from exposed surfaces in shallow waters, but unchecked growth of green filamentous algae can inhibit larval settlement. Tube worms die when tubes become clogged with sediment or overgrown by encrusting epibiota. Some species have tube or opercular adaptations that may reduce the effects of competition and predation by epifauna. Post settlement mortality is greater among the Spirorbidae than the Serpulidae. This may be due to the small size of the spirorbids or to the oxygen requirements of the brooded embryos. In the Sudanese Red Sea spirorbids occurred at depths less than 50 m, while the serpulids were found at all depths from the intertidal to bel

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01969.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Allelic variation at 13 sites for the intertidalPomatoceros lamarckii(Quatrefages) and at six sites for the sublittoralP. triqueter(L.) in North‐West Europe, when examined at 19 metabolic enzyme loci, showed significant differences between sites in the frequencies of the various enzyme morphs. There was no readily interpretable geographic or environmental trend. The Hardy‐Weinberg equilibrium was maintained at almost all loci and all sites. The genetic distance between populations was very small in comparison with the difference between the two species.Colour morphs ofP. triquetershowed a clear latitudinal cline with blue and brown morphs predominating at more northerly latitudes, and grey, orange and red morphs at more southerly latitudes.Interlocality variations in allele frequency, though statistically significant, were never sufficient to alter the order of frequency of the two or three commonest alleles, so that the frequency of all but rare alleles showed a consensus throughout the ranges studied for each species. Accounting for local genetic patchiness in gene frequencies in species with pelagic larvae raises problems if the alleles are selectively neutral; accounting for wide geographic uniformity raises problems if alleles are selected for or against by environmental fact

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01970.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The upper reaches of Milford Haven and the Daucleddau have an unusually rich fauna because of their depth and the abundance of hard substrata. The estuary is of commercial importance both in its potential for shell‐fisheries and its development as a major oil port, bringing risks of serious pollution. Recent extensive sublittoral studies have added numerous faunistic records and have also cast further light upon changes in the zonation of sedentary marine animals as they penetrate brackish regions. Re‐survey of a transit across the channel near Lawrenny has shown changes largely related to the spread of a vigorous immigrant competitor of the native oys

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01971.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Large numbers of the tube‐building polychaeteDiopatra leuckartiKinberg form extensive mounds of sand on a Hawaiian reef‐fiat, providing a stable environment with plentiful resources to support a diverse invertebrate community. The vertically oriented tubes reach densities of 21 800 m‐2and the projecting tubes trap drift algae and sediments which are sources of food and tube‐building materials for the associated community. There are 22 polychaete species, six crustacean species and eight of other taxa represented, withLeptochelia dubia(tanaid) andCapitella capitala(capitellid) as the dominant organisms, reaching densities of 32 800 m‐2and 11600 m‐2, respectively. Both species form fine mud tubes on the sediment surface among theDiopatratubes. Other numerically abundant taxa are the deposit feeders comprising orbiniid, capitellid and cirratulid polychaetes, small crustaceans and a holothurian. Crustaceans, fishes and polychaetes are the primary predators. Both low salinities (15–26%, at low tides) due to ground water seepage and fine sediments are probably major factors affecting the species composition of theDiopatramounds. They also act as a buffer between the reef‐flat and the beach, serving to reduc

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01972.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Field and laboratory experiments show that endogenous circatidal rhythms in coastal animals are entrained by exposure to real or simulated tidal cycles of hydrostatic pressure, temperature, salinity, wave agitation, immersion and light. Short pulses (2–3 h) of simulated high tide induce slight phase advances or delays in the free‐running circatidal rhythm of groups of experimental animals, depending upon the time of application. Phase‐response curves derived in this way are less clear‐cut than for typical circadian rhythms, but their pattern suggests that tidally rhythmic behaviour is controlled by truly circatidal (and not circadian) oscillators. The underlying circatidal oscillators appear, in general, to be fairly stable, suggesting that populations of coastal animals are relatively unsusceptible to irregularly timed environmental stimuli associated, say, with severe

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01973.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The responses of marine invertebrates to changes in hydrostatic pressure within the + 1000 mbar range are reviewed and some response parameters are considered in an attempt to set the phenomenon of barosensitivity in the more general context of animal irritability. Possible mechanisms of transduction are discussed and, in the absence of any identifiable baroreceptor, a comparative psychophysical approach is advocated as a possible means of elucidating further the fundamental properties of such pressure‐sensitive system

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01974.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Morphological adaptations of the littoral hemipteranAepophilus bonnaireiSign, to its environment are examined. Particular emphasis is paid to the distribution of the plastron formed by microtrichia and structures around the thoracic spiracles.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1984.tb01975.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY