污损性管栖多毛类生态特点及研究展望

污损性管栖多毛类属环节动物门,主要由龙介虫科(Serpulidae)、螺旋虫科(Spirorbidae)、缨鳃虫科(Sabellidae)和蛰龙介科(Terebllidae)4科55种组成,以华美盘管虫(Hydroides elegans)、内刺盘管虫(H.ezoensis)、龙介虫(Serpula vermicularis)和克氏无襟毛虫(Pomatoleios kraussii)等种类为优势种,通常成批的附着在物体表面,严重影响人工设施的安全和性能。污损性管栖多毛类的分布具有明显的地域性和季节性,并与深度有关。今后工作应进一步开展管栖多毛类基础生物学研究,探讨外来种的入侵及影响,丰富和发展生态和分类等方面的研究内容。     

Serpulids and other calcareous tube-dwelling encrusting polychaetes from the Early Cretaceous Agrio Formation (Neuquén Basin,Argentina)

Serpulids and other related tube-dwelling polychaetes are often ignored when found as fossil remains. They are, however, a widespread and important group today, and abundant literature has been published on them. Knowledge of fossil serpulids is centered on European material, and little has already been done on South American fossil calcareous tubes. In this paper, seven serpulid and sabellid morphotypes are described from the Early Cretaceous marine Agrio Formation of Argentina, revealing a diversity of worms recorded as encrusters on bivalves, ammonites and corals. Sabellids are represented by Glomerula cf. serpentina. Serpulids are represented by two subfamilies: “Serpulinae” includes Mucroserpula mucroserpula, Parsimonia antiquata, Placostegus cf. conchophilus, Propomatoceros semicostatus and P. sulcicarinatus; Spirorbinae is represented by heavily worn tiny coiled tubes assigned to ?Neomicrorbis. Serpulids and sabellids are one of the main components of the mollusk-encrusting fauna recorded in the Agrio Formation, along with small oysters but much more diverse. They are most commonly found as post-mortem encrusters, but some cases of unquestionable living interaction are also found, such as serpulid tubes embedded on coral branches. They are often overgrown by bryozoans, and sometimes by oysters; they frequently occur aggregated.     

Data on distribution and biology of poachers agonidae from the northwestern part of the Bering Sea

On the basis of materials of 1996–2003, specific features of spatial and seasonal distribution of four species of Agonidae (Percis japonica, Sarritor frenatus, S. leptorhynchus, and Aspidophoroides bartoni) in the northwestern part of the Bering Sea are considered. In this area of the studied species, P. japonica is found in catches most frequently (occurrence reaches 81.8%); the rarest here is S. leptorhynchus (0.7–7.0%). P. japonica begins to spawn in mid-July, and S. frenatus terminates spawning in the second ten-day period in August. Mass (50%) sexual maturation of female P. japonica occurs at a length of 29 cm, and of males, at 23 cm; in S. frenatus, at 24–25 and 23 cm, respectively. The individual absolute fecundity of P. japonica averages 6361 eggs, and oocyte diameter, 2.9 mm; of S. frenatus, 2848 eggs and 1.53 mm, respectively. The bulk of feeding of P. japonica is formed by polychaetes; next in importance are amphipods and caprellids. The bulk of feeding of S. frenatus is formed by amphipods; polychaetes, isopods, and euphausiids (in decreasing order) are also important in the feeding of this species.     

Chaetal arrangement provides no support for a close relationship of Sabellidae and Sabellariidae (Annelida)

Sabellid and sabellariid polychaetes are regarded as sister groups in a number of recent phylogenetic analyses. This is based mainly on a shared specific arrangement of chaetae referred to as chaetal inversion. Remarkably, the uncini have a notopodial position in the abdomen, whereas capillary chaetae occur in the neuropodia in both taxa in contrast to the situation in putative relatives. However, in sabellids uncini and capillary chaetae change their position completely at the border between thorax and abdomen, whereas uncini are missing in the parathorax of Sabellariidae. Due to this difference the significance of the chaetal inversion for systematics has been subject to discussion for years. Serial semithin sections of parapodia of the Sabellidae Sabella pavonina, Branchiomma bombyx, Fabricia stellaris, and of the Sabellariidae Sabellaria alveolata were studied in order to obtain detailed information on their chaetal arrangement and sites of chaetal origin. SEM investigations and computer-aided 3D-reconstructions provide deep insight into the spatial organization of the rami. Though differing externally, the principal chaetal arrangement and the location of the formative sites turned out to be almost identical within the species of Sabellidae. Most chaetae are aligned in straight transverse rows with a dorsal site of origin within neuropodia and a ventral one in notopodia as is common in sedentary polychaetes. Semicircular and spiral arrangements are revealed to be modified transverse rows. Only in thoracic notopodia does an additional dorsocaudal formative site form distinct rows. The chaetal inversion in Sabellidae is additionally characterized by an abrupt change of capillary chaetae and uncini along with a sudden change of the parapodial morphology at the border between thorax and abdomen. All chaetae of S. alveolata are aligned in transverse rows with the same location of the formative sites as in sabellids and other sedentary polychaetes. However, in contrast to sabellids the chaetae are not inverted across a parathoracic abdominal border. Moreover, there is no inversion of the parapodial structure from parathorax to abdomen and the neuropodial chaetal composition changes gradually from parathorax to abdomen. The chaetal arrangement in Sabellariidae thus cannot be described as inverted along the body-axis as in Sabellidae. Evolutionary steps implied by the assumption of an inverted chaetal pattern in a supposed common ancestor are discussed. It is concluded that the specific chaetal arrangement of Sabellidae and Sabellariidae arose independently and therefore provides no support for a sistergroup relationship of sabellids and sabellariids.     

Tube building by the amphipods Lembos websteri Bate and Corophium bonnellii Milne Edwards

Lembos websteri Bate and Corophium bonnellii Milne Edwards are tubicolous. The morphology of tubes collected from Laminaria holdfasts is described and contrasted with that of tubes built amongst filamentous algae in a wave-sheltered environment. In both species tube length is a function of animal length. Corophium build tubes with openings raised above the substratum more commonly than Lembos, and will construct mats of tubes away from solid surfaces; Lembos tend to build against solid surfaces. Tube construction appears to depend upon the ‘knitting’ activity of the first two pairs of peraeopods, utilizing a secretion containing acid and sulphated mucopolysaccharides. The process of tube construction on substrata of known granulometry and the morphology of tubes built in the laboratory are described. The burrowing capabilities of both species are compared. On sand, Lembos tend to build on the sediment surface, whilst Corophium tend to burrow into the substratum. Corophium begin tube building after transference to a new situation much sooner than Lembos, with female Lembos starting to build sooner than male Lembos, Corophium can build a covering tube in < 15 min. In the absence of extraneous material, both species line glass tubes with a meshwork of mucoid filaments. In empty dishes, mucoid tubes are rarely built. The ability of Lembos to colonize wave-exposed sites may be related to its preference for more sheltered spaces within kelp holdfasts.     

Mechanisms of spatial competition in marine soft-bottom communities

Two kinds of biogenic structures, roots of seagrasses and tubes of invertebrates, were found to reduce the mobility of a variety of burrowing species, including two polychaetes (Abarenicola pacifica Healy & Wells, A. claparedii Healy & Wells), two bivalves (Macoma nasuta Conrad, Clinocardium nuttalliiConrad), two crustaceans (Upogebia pugettensis (Dana), Callianassa californiensis Dana), a holothurian (Leptosynapta clarkii Heding), and an echinoid (Dendraster excentricus (Eschscholtz)). Comparisons of burrowing in similar sediments showed that: (a) all species had about a two-fold increase in mean time to burial in dense tube-mats of polychaetes and crustaceans; (b) hard-bodied taxa were particularly restricted by roots of Zostera marina L. and were often incapable of penetrating them; (c) roots and tubes together had the greatest impact, with mobility 3 to 37 times slower; and (d) burrowing ability increased when sediments were “pre-burrowed” for 1 day. Comparisons of burrowing rates in different sediments showed effects of physical origin (sediment compaction or sorting). Overall these physical effects were second to those of purely biogenic origin, sediment binding and cohesion by roots and tubes. Nonetheless, physical effects exceeded those of extremely high densities of tube-builders (3160 individuals ·0.01 m^?2). In all substrata the movement of larger individuals, and the larger of morphologically similar pairs of species (listed second above), were more restricted by roots and tubes than were smaller ones. The results suggest a general mechanism by which dense assemblages of tube-builders and seagrasses may restrict older and larger burrowing organisms. Because physical properties of the sediment and the abundance of other burrowers are also factors affecting mobility, it is not now possible to predict what situations will render this mechanism of interaction important to natural communities.     

The utilization of fly ash by two tube-building polychaetes

Benthic tube-building polychaetes which utilize sediment particles have been found to incorporate fly ash in their tubes. Experiments were conducted on North Sea specimens of Myriochele oculata Zachs and Pectinaria koreni (Malmgren) in artificial sediments offering a range of fly ash concentrations. A marked selection for non-ash particles was shown by Myriochele oculata, and a marginal selection against ash by Pectinaria koreni. It is suggested that this selection is based on the inorganic nature of fresh ash particles, assuming initial collection for feeding: as ash particles at the sea bed develop an organic component, such selection will disappear.     

Characterization of the Lipopolysaccharides and Capsules of Shewanella spp.

Electron microscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis with silver staining and ¹H, ¹³C, and ³¹P-nuclear magnetic resonance (NMR) were used to detect and characterize the lipopolysaccharides (LPSs) of several Shewanella species. Many expressed only rough LPS; however, approximately one-half produced smooth LPS (and/or capsular polysaccharides). Some LPSs were affected by growth temperature with increased chain length observed below 25°C. Maximum LPS heterogeneity was found at 15 to 20°C. Thin sections of freeze-substituted cells revealed that Shewanella oneidensis, S. algae, S. frigidimarina, and Shewanella sp. strain MR-4 possessed either O-side chains or capsular fringes ranging from 20 to 130 nm in thickness depending on the species. NMR detected unusual sugars in S. putrefaciens CN32 and S. algae BrY^DL. It is possible that the ability of Shewanella to adhere to solid mineral phases (such as iron oxides) could be affected by the composition and length of surface polysaccharide polymers. These same polymers in S. algae may also contribute to this opportunistic pathogen's ability to promote infection.     

Characterization of the calcium biomineral in the radular teeth of Chiton pelliserpentis

The radula in a group of molluscan invertebrates, the chitons (Polyplacophora), is a ribbon-like apparatus used for feeding and which bears a series of distinctive mineralized teeth called the major lateral teeth. While some chiton species deposit only iron biominerals in these teeth, many others deposit both iron and calcium. In this study, the calcium biomineral in the teeth of one of the latter types of species, the Australian east-coast chiton, Chiton pelliserpentis, has been isolated and examined for the first time. Spectroscopic and crystallographic techniques have identified the biomineral as a carbonate-substituted apatite with significant fluoride substitution also likely. Fourier-transform infrared and laser Raman spectroscopy indicated that the carbonate content was less than that of either bovine tibia cortical bone or human tooth enamel. X-ray diffraction analysis showed the biomineral to be poorly crystalline due to small crystal size and appreciable anionic substitution. The lattice parameters were calculated to be a=9.382?Å and c=6.883?Å, which are suggestive of a fluorapatite material. It is postulated that structural and biochemical differences in the tooth organic matrix of different chiton species will ultimately determine if the teeth become partly calcified or iron mineralized only.     

Electron microscopy of muscle phosphorylase a

Electron microscopy of negatively stained preparations of phosphorylase a (tetrameric form) from solutions with and without added protamine revealed three characteristic types of particle images. In preparations with added protamine several types of crystalline formation were observed: three types of plane monolayers, tubes and small three-dimensional crystals. The tubes have been studied by optical diffraction and filtering. In the main class of tubes the particles form $\text{26}\text{9}$ three-start helices (it may well be that narrow tubes with different parameters exist). Now and again, one can observe tubes twice as large in diameter, and tubes with two-layer walls. Analysis of the images of particles in solution and in crystalline formations showed that their structure can be characterized in terms of one model consisting of four elongated bent subunits arranged with the point-group symmetry 222 at the vertices of a tetrahedron. The structure of phosphorylase b particles, previously studied (Kiselev et al., 1971), can also be characterized satisfactorily by the same model. The difference in the structure of these two forms expresses itself in a different character of mutual aggregation of the molecules in plane layers, and in the parameters of the helical packing of the molecules in tubes.     

An assessment of the status of Polycirridae genera (Annelida: Terebelliformia) and evolutionary transformation series of characters within the family

A phylogenetic analysis was performed to determine the monophyly of non‐monotypic genera of the terebelliform family Polycirridae, i.e. Polycirrus, Amaeana, Lysilla, and Hauchiella, and the evolution of characters among members of this clade. The monotypic genera, Enoplobranchus and Biremis, were also included, together with members of both known species in Hauchiella. Representative species were included for remaining genera: 14 species of Polycirrus, six species of Amaeana, and six species of Lysilla. Out‐groups consisted of representatives of Spionidae, Cirratulidae, and Sabellariidae, as well as several species of Telothelepodidae. A total of 40 in‐ and out‐group species were coded for 50 subjects (‘characters’) and 117 subject–predicate relationships (‘states’). Although results are consistent with recent phylogenetic studies within Terebelliformia that suggest Polycirridae monophyly, only Hauchiella was found to be monophyletic, albeit part of the more inclusive clade comprising remaining polycirrid genera. Evolutionary transformation series are discussed for selected characters in relation to the non‐monophyly of Polycirrus, Lysilla, and Amaeana. Implications for the use of supraspecific taxa as ‘taxonomic surrogates’ are highlighted. The definition of Polycirridae is emended. © 2015 The Linnean Society of London     

Sites of self-pollen tube inhibition in Papaveraceae (sensu lato)

Papaver rhoeas (Papaveraceae) has a well-characterized gametophytic self-incompatibility system in which self-pollen tube growth ceases either just before, or just after, emergence from the copal aperture. Papaver flowers are unusual, however, in having flat stigmatic rays sitting directly on top of the hard ovary and no style. Immediate self-pollen arrest might be required with this floral architecture. There is much variation in floral architecture among Papaveraceae and self-incompatibility is widespread. However, there are no reports of the site of self-pollen tube inhibition in Papaveraceae other than P. rhoeas. We examined the site of self-pollen tube inhibition in four species (Argemone munita, Lamprocapnos spectabilis, Eschscholzia californica, and Platystemon californicus) representing a broad phylogenetic and morphological sample of Papaveraceae. Squash preparation was used for species with soft stigmas whereas woody tissue was sectioned with a cryostat and images were stitched into a mosaic to visualize pollen tubes on whole stigmas. For three species, self-pollen tube inhibition appeared similar to that described for P. rhoeas. Self-pollen tubes were arrested before any substantial penetration of female tissue and usually did not grow longer than 100?μm. In the fourth species, A. munita, self-pollen tubes grew up to 500?μm in length. However, self-pollen tubes appeared to grow along the stigmatic spines, and growth ceased once tubes contacted the stigma surface. Despite variation in floral architecture, rapid arrest of self-pollen tubes occurred before or just after penetration of female tissue in all species, consistent with the hypothesis that members of the family share the same incompatibility mechanism.     

Variation in cuticular lipid profiles of black butterflies of the genus Papilio in Japan

Insect (epi)cuticular lipids characterize sex and species and often play an important role in mating behavior. We previously revealed that two black-colored swallowtail butterflies, Papilio polytes and Papilio protenor, show sexual dimorphism and species specificity in cuticular lipid composition and that P. polytes males use specific monoene components for mate discrimination. These findings suggest that their closely related species may have different profiles of cuticular lipids. We examined the cuticular lipid compositions of five Papilio species (P. bianor, P. maackii, P. helenus, P. macilentus, and P. memnon), closely related and sympatric to P. polytes and P. protenor, and discussed whether it is possible to discriminate between sexes, and between species based on their chemical profiles. The cuticular lipids consist mainly of C23–C31 aliphatic hydrocarbons, in which n-tricosane, n-heptacosane, and n-nonacosane are predominant. Several aliphatic ketones, aliphatic acids, and oxygenated terpenoids were also identified as major components shared by several species. There were no components exclusive to a particular species. Conspecific males and females shared most of the components but were mostly distinguishable based on their composition. Moreover, P. helenus males, P. polytes females, and P. protenor females had two different phenotypes of lipid composition. Although unrelated to the genetic lineage, the seven species were classified into four clusters based on their lipid profiles. The first cluster was composed of only P. memnon. The other six species were broadly classified into three clusters consisting of subclusters for each species: 1) P. polytes, P. helenus, P. macilentus, and several P. protenor females; 2) P. bianor and P. protenor; and 3) P. maackii and several P. helenus males. These results indicate that cuticular lipid profiles characterize the species and sex of the Papilio species and may be responsible for mate discrimination among them.     

Movement of Five Nematode Species through Sand Subjected to Natural Temperature Gradient Fluctuations

Temperature gradient fluctuations that occur naturally as a result of heating and cooling of the soil surface were reproduced within 15-cm-d, 15-cm-long acrylic tubes filled with moist sand. Sunny and rainy periods during the late summer in eastern Texas were simulated. Five ecologically different nematode species were adapted to fluctuating temperatures for 20-36 hours at a simulated depth of 12.5 cm before being injected simultaneously into the centers of tubes at that depth. When heat waves were propagated horizontally to eliminate gravitational effects, the movement of Ditylenchus phyllobius, Steinernema glaseri, and Heterorhabditis bacteriophora relative to the thermal surface was rapid and largely random. However, Rotylenchulus reniformis moved away from and Meloidogyne incognita moved toward the thermal surface. When heat waves were propagated upward or downward, responses to temperature were the same as when propagated horizontally, irrespective of gravity. The initial direction of movement 1.5 hours after introduction to 20-era-long tubes at five depths at five intervals within a 24-hour cycle indicated that M. incognita moved away from and R. reniformis moved toward the temperature to which last exposed. Differences in movement of the five species tested relative to gravity appeared related to body length, with the smallest nematodes moving downward and the largest moving upward.     

Nemertea inhabiting the Haploops (Amphipoda) community of the northern Øresund with special reference to the biology of Nipponnemertes pulcher (Hoplonemertea)

The densities of nemerteans and associated fauna on a soft-bottom sampling station (27–30 m deep) in the Øresund were determined from 47 cores (each 135 cm² in cross-section; 20 + cm deep) collected from September to December 1989; these data were compared with 14 cores taken from the same location in December 1982. Nine species of nemerteans were identified from cores and dredge samples: Palaeonemertea — Callinera-like sp.; Heteronemertea — Cerebratulus fuscus, C. marginatus, Lineus bilineatus, Micrura fasciolata, M. purpurea; Hoplonemertea — Amphiporus bioculatus, A. dissimulans, Nipponnemertes pulcher. Mean numbers of heteronemerteans were 32 and 10 m^?2 in 1982 and 1989, respectively, and hoplonemerteans were 90 and 71 m^?2 , respectively. Only one palaeonemertean was collected during both years. Mean densities of the dominant species, N. pulcher, were similar for the two years, 74 and 68 m^?2. The dominant groups of macrofauna (n m^?2) in 1989 were ostracods (1028), amphipods (618), polychaetes (514), and ophiuroids (449). Amphipods (>90% Haploops spp.) and polychaetes (at least 30 spp.) are the major potential prey for hoplonemerteans and heteronemerteans, respectively. Laboratory feeding experiments with N. pulcher revealed that it consumed amphipods (Haploops tenuis and H. tubicola) at a rate of 2.6 worm^?1 d^?1 during the first 12 hours, but after 36 hours and beyond the rate was maintained at approximately 0.2 worm^?1 d^?1. Beyond 12 hours this nemertean showed a tendancy to only partially evacuate its prey. It was demonstrated experimentally that N. pulcher has a supply of toxin capable of killing six amphipods in approximately one hour. Limited tests showed that N. pulcher fed on the cumacean Diastylis tumida, but not on the amphipod Maera loveni or the ostracod Philomedes globosus, and that Amphiporus dissimulans readily attacked Haploops spp., but not Maera or Philomedes. Although the results of laboratory experiments are tentative, they do suggest that suctorial hoplonemerteans can exert a potentially significant effect on benthic communities. Employing seven species of polychaetes as prey for Cerebratulus fuscus and Micrura fasciolata, only the latter responded positively to one of them, Glycera alba. The hermit crab Pagurus bernhardus violently rejected N. pulcher in all feeding trials.     

The distribution and function of microtubules in nutritive tubes

The density and distribution of microtubules in the nutritive tubes of three hemipteran insects, Corixa punctata, Notonecta glauca and Dysdercus cingulatus, were analysed from electron micrographs by computer. Both parameters varied amongst all three species, the density of microtubules in Corixa being approximately three times that seen in Dysdercus. The density and distribution of microtubules within the nutritive tubes correlated directly with the size of particle transported by them, suggesting that the microtubules may act as a sieve to preclude certain cellular components from entering the tubes. If microtubules are further involved in the generation of motive force for cytoplasmic transport along the nutritive tubes, this function is not dependent upon the number of microtubules, or upon their arrangement with respect either to each other or to the particle being transported.     

Assessment of site specific benthic impact of floating cage farming in the eastern Hios island, Eastern Aegean Sea, Greece

The site specific impact on the benthic fauna was assessed within a 4.64 km² area of intensive aquaculture situated on the eastern side of Hios island (Aegean Sea, Greece) at 11 stations seasonally between November 2000 and October 2001. The benthic fauna showed marked changes in species numbers, diversity and faunal abundance between farm and control sites. The polychaetes Nereis diversicolor, Scolelepis fuliginosa and Capitella capitata were the most dominant species at the farm sites (35% of the total abundance), whilst the most dominant species at the control sites were the polychaete Hyalinoecia brementi and the sipunculid Aspidosiphon muelleri (23% of the total abundance). Species richness, diversity and evenness were higher at the control sites whereas numerical abundance was higher at the farm sites. K-dominance curves suggest a minor impact on the benthic community at the farm sites and temporal changes on macrobenthic assemblages.     

Food contents of the eastern gray whale Eschrichtius robustus Lilljeborg, 1861 in the Mechigmensky bay of the Bering Sea

Food compositions in 82 individuals of the gray whale Eschrichtius robustus from Mechigmen Bay in the Bering Sea were analyzed in 2007?C2009. Animals of 12 taxonomic groups were revealed in the food boluses of whales; amphipods and polychaetes prevailed by biomass and frequency of occurrence. The average specific biomass of amphipods was 54.2?C71.7% and the frequency of occurrence reached 96.3?C100%; those of polychaetes were 19.5?C37.2 and 85.2?C100%, respectively. The comparison of the feeding of E. robustus in 2007?C2009 and 1998?C1999 displayed that the taxonomic composition of the eaten animals remained the same, but the sizes of the groups changed. In 2007?C2009, 68 species of amphipods were recorded in the whale stomachs; the input to biomass was counted for six species, Anonyx nugax (31.7%), Ampelisca macrocephala (22.3%), Psammonyx kurilicus (15.3%), Ampelisca eschrichti (9.1%), Hippomedon denticulatus orientalis (4.3%), and Pontoporeia femorata (4.6%). As in 1998?C1999, the first two species prevailed. In percentage terms, the greatest portion of the whale bolus was based on most abundant benthic species.     

Reef fish diversity components as indicators of cumulative effects in a highly impacted fringe reef

The main goal of our research was to determine which indicators describing cumulative stress might better explain the differences observed in diversity components of reef fish assemblages off Havana City, Cuba. A total of 35,078 individuals of 119 species were counted in 480 stationary point censuses. Counts were distributed among three zones with different levels of pollution and four habitats with different wave stress. Four indexes of diversity components (S, H′, J′ and PIE) were calculated and correlative analyses performed to explore the best indicators of cumulative effects explaining observed variation. High correlation was found between all diversity components and two indexes of cumulative effects (ICE) built after distinct criteria. In the first case, pollution and wave action were combined following an interactive model. In the second case, an empirical ICE was obtained by totaling the abundance indicators of three groups of organisms, namely sponges, sabellid polychaetes and filamentous algae.