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1.
Vargas, S., Erpenbeck, D., Göcke, C., Hall, K. A., Hooper, J. N. A., Janussen, D. & Wörheide, G. (2012) Molecular phylogeny of Abyssocladia (Cladorhizidae: Poecilosclerida) and Phelloderma (Phellodermidae: Poecilosclerida) suggests a diversification of chelae microscleres in cladorhizid sponges. —Zoologica Scripta, 42, 106–116. The taxonomic placement of Abyssocladia Lévi, 1964 (Poecilosclerida) is controversial, having been assigned at various times to three different families (Mycalidae, Cladorhizidae and Phellodermidae) in two different suborders (Mycalina and Myxillina, respectively), since its inception in 1964. It shares the general body plan with the carnivorous sponge family Cladorhizidae (Mycalina), including the lack of an aquiferous system. Nevertheless, it also has chela spicules apparently identical to those in Phelloderma Ridley & Dendy 1886 (Phellodermidae, Myxillina). The ongoing debate on the position of Abyssocladia ultimately reduces to a discussion on the use of chelae morphology to infer phylogenetic relationships within Poecilosclerida. Here, we infer the phylogenetic relationships of the genera Phelloderma and Abyssocladia using two independent molecular markers (28S rDNA and COI), showing that Abyssocladia is not closely related to Phelloderma and belongs in Cladorhizidae. We suggest that despite their complexity, chelae morphology can evolve independently in different poecilosclerid lineages and as such might be potentially misleading as indicator of the phylogenetic history of the group. We also provide the first phylogenetic analysis of the carnivorous sponge family Cladorhizidae and give first insights into the evolution of this feeding mode in Poecilosclerida and, more generally, in Porifera.  相似文献   

2.
Nine new species of carnivorous sponges, namely Cladorhiza segonzaci , Chondrocladia koltuni , Chondrocladia lampadiglobus , Asbestopluma agglutinans , Asbestopluma ( Helophloeina ) formosa , Abyssocladia huitzilopochtli , Abyssocladia inflata , Abyssocladia dominalba and Abyssocladia naudur , are described. The subgenus Helophloeina Topsent, 1929 and the genus Abyssocladia Lévi, 1964 are revived and redefined, with an identification key for Abyssocladia which at present includes seven species. Eight of the sponges were collected from the French IFREMER manned submersible Nautile near active hydrothermal sites of the East Pacific Rise and of the North Fiji and Lau Basins, one from the Russian submersible Mir 2 in the Northwest Pacific near Bering Island, and one from the US submersible Alvin south of Easter Island. Their life conditions are described from direct observations from the submersibles. Some remarks are presented on the taxonomy of Cladorhizidae and more generally of carnivorous Poecilosclerida. The study suggests a very high degree of diversity in the deep Pacific carnivorous sponges.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 553–584.  相似文献   

3.
The reproductive development of the Demospongiae species Halisarca dujardini (Halisarcida), Myxilla incrustans and Iophon piceus (Poecilosclerida) from Chupa Inlet (Kandalaksha Bay, the White Sea) was studied histologically during 1982-1994 and 1997. These species are all viviparous. Halisarca dujardini inhabits shallow waters (1.5-5 m); M. incrustans and I. piceus are common in a more stable environment at depths between 15 and 25 m. Initiation of sexual reproduction stages is dependent upon water temperature. Reproductive effort is low in Myxilla incrustans and I. piceus (reproductive elements contribute 7.3% and 12% of maternal tissue volume respectively), but much higher in H. dujardini (up to 69% of the parental tissue volume). Reproduction leads to localized destruction of maternal tissue for M. incrustans and I. piceus and complete disorder of central and basal parts of the choanosoma of H. dujardini after each period of reproduction. Myxilla incrustans and I. piceus reproduce throughout the hydrological summer, but reproduction in H. dujardini is restricted to 3 weeks. The average life span of M. incrustans and I. piceus is more than 4 years, and that of H. dujardini is about 7-12 months. The data suggest that M. incrustans and I. piceus are K-strategists, whereas H. dujardini is an r-strategist.  相似文献   

4.
Chondrocladia (Symmetrocladia) lyra subgen. nov., sp. nov., is described from northeast Pacific sites at Escanaba Ridge and Monterey Canyon at depths of 3316–3399 m. Two retrieved specimens are described in detail, while variations are described in ten photographed or videotaped specimens. The basic structure, termed a vane, is harp‐ or lyre‐shaped. From 1 to 6 vanes extend by radial growth from the organism's center. The orientation among the vanes is approximately equiangular, such that together they display pentaradiate, tetraradiate, triradiate, or biradiate symmetries. Each vane is formed by a horizontal stolon supporting a series of upright, equidistantly spaced branches each of which terminates at its apex in a swollen ball in all observed specimens except the paratype. Swellings occur midway along the branches in the holotype, but not in the paratype. A linear row of filaments project from the sides, front, and back of each branch, and also from the tops of each stolon. The terminal balls are the sites of spermatophore production and release; mid‐branch swellings are sites of oocyte maturation. The two megasclere spicule types have specific distributions; styles support rhizoids, stolons, and branches, while subtylostyles support filaments and terminal balls. Anchorate isochelae cover all surfaces. Enclosed crustacean prey on branches and stolons provide direct evidence of carnivory. The structure of the vanes maximizes surface area for passive suspension feeding. Increased surface area could also maximize spermatophore capture, with the sigmas projecting from the spermatophore surface being caught by projecting isochelae on filaments. Swellings on filaments are snared spermatophores, firmly fused to recipient tissues and undergoing destruction. Spermatophores on filaments are present in branch swellings containing early and mature oocytes. Oogenesis and maturation occur only in proximity to branch swellings, suggesting that development is induced by spermatophore reception. Symmetrical development of uniserial branched stolons (the vanes) characterized members of the new subgenus Symmetrocladia.  相似文献   

5.
The process of microsclere secretion was examined in vivo through glass coverslip implants in three species of the genus Mycale from São Sebastião channel, southeastern Brazil: Mycale (Aegogropila) angulosa, Mycale (Arenochalina) laxissima, and Mycale (Carmia) microsigmatosa. All three species adhered well to coverslips and developed normally through at least 2 weeks. Similar experiments with different species (Cinachyrella alloclada, Amphimedon viridis, Haliclona melana, and Aplysina caissara) were also successful with one exception (the cartilaginous Chondrilla nucula), indicating that the method can be applied to most demosponges. Microsclerocyte size varied according to the type of microsclere secreted, but all were elongated to fusiform and had small, anucleolated nuclei. Spicules were transported by microsclerocytes alone, without any other cell type ("helper cells") involved. Secretion of a microsclere was performed by a single sclerocyte. Although some axial filaments were found free in the mesohyl, all microsclere secretion in these animals was fully intracellular. Normal axial filaments were observed in most types of microscleres of the Mycale species (sigmas, toxas, and microxeas). Timed observations of sclerocytes suggest that immature spicules with the aspect of short straight rods with thick ends might be the precursors of the anisochelae. Observed differences in the size versus number of toxa secreted may indicate either the presence of two distinct subpopulations of toxa-producing microsclerocytes or that the initial number of axial filaments at the beginning of silica deposition may determine the final size of the spicules. Although other microscleres such as sigmas and chelae are secreted in a one cell-one spicule basis, several toxas and microxeas can be secreted simultaneously in a single cell.  相似文献   

6.
Abstract. We describe the morphology and ultrastructure of the free-swimming larvae of the sponge Crambe crambe , one of the most abundant encrusting sponges on shallow rocky bottoms of the western Mediterranean. Larvae of C. crambe are released in July and August. The larva is uniformly flagellated except at the posterior zone. Flagellated cells are extraordinarily slender, elongate, and sinuous and form a pseudo-stratified layer. Their distal zone contains abundant mitochondria, some small vesicles, a Golgi complex, and the basal apparatus of the flagellum. Abundant lipid droplets are present throughout the cell. The nucleus is most often in a basal position. The flagellum projects from the bottom of an asymmetrical socket formed by cytoplasmic expansions. The basal body extends in a conical tuft and a laminar rootlet in close association with the Golgi system. The cells at the posterior pole are flat and polygonal on the surface, with long overlapping pseudopodia in the typical shape of a pinacoderm. Sparse collagen is present throughout the whole larva including the flagellated layer. Archeocytes and sclerocytes are abundant in the posterior region. Typical collencytes and spherulous cells seem to be absent. Intracellular and extracellular rod-like bacteria with conspicuous fimbria occur exclusively in the posterior region of the larva. The asymmetrical cytoplasmic prolongations, which surround the flagellum, and the basal apparatus of the flagellum are suggested as the sites of stimulus reception and triggering of locomotor responses, respectively. This ultrastructural study of the larva of C. crambe has shown features directly linked to its behavior and ecology.  相似文献   

7.
Tedania ignis (Duchassaing and Michelotti, 1864), the fire sponge, is common throughout the tropical western Atlantic, and is a popular species for studies of ecology, larval biology, and chemistry. T. ignis is readily consumed by seagrass-dwelling starfish, and so finding sponges similar to this species in a seagrass meadow provoked closer scrutiny. A variety of ecological, morphological, and molecular traits consistently and unambiguously distinguish T. ignis from a cryptic sympatric congener, here described as Tedania klausi, n. sp. Starfish that consume T. ignis reject T. klausi, and angelfish consume T. klausi less quickly. In Belize, T. ignis individuals transplanted to a seagrass meadow inhabited by T. klausi were consumed by starfish, and individuals of T. klausi transplanted to a mangrove-lined creek in which T. ignis flourishes, died. In Panama, many individuals of T. klausi were diseased in May 2004, while adjacent individuals of T. ignis were unaffected. Spicule types are the same in the two forms, and sizes overlap; but within individuals, the relative sizes of styles and tylotes differ in a pattern that distinguishes the two forms. Comparison of DNA sequences for mitochondrial cytochrome c oxidase subunit I (COI) revealed that 8 single nucleotide mutations consistently differ between the two forms regardless of habitat (seagrass vs. mangrove) and geographically separated sites (Belize vs. Panama).  相似文献   

8.
In this study, we estimated the extent of asexual reproduction and genotypic diversity at the intra- and interspecific levels in sponges of the genus Chondrilla in the Caribbean and along the coast of Brazil. Allozymes were used to identify the genotypes of specimens of Chondrilla in each location. The four species studied displayed a large variation in the extent of clonal reproduction and genotypic diversity, with the two species from the Bahamas having a greater proportion of asexually produced individuals than those along the coast of Brazil. Conspecific Brazilian populations of Chondrilla sp. had large differences in clonality: the population from a heterogeneous environment and under the influence of a strong upwelling had little clonality (7%), whereas the population located 350 km south along the coast, in a more homogeneous and temporally stable environment, had a five-fold larger (39%) proportion of asexually derived individuals. Finally, we were able to confirm that, besides fission, the genus Chondrilla displays a second mode of asexual reproduction, by fragmentation of teardrop shaped individuals.  相似文献   

9.
All the currently known sponge species bearing placochelae or placochelae-like spicules (i.e. belonging to the genera Guitarra, Coelodischela, Tetrapocillon, Euchelipluma , and Hoplakithara ) have been reviewed and their relationships delineated by cladistic analysis. A matrix of 18 taxa and 14 characters is included. The species Isodictya palmata and Esperiopsis fucorum were used as an outgroup, because they shared either monactines or diactines and smooth palmate isochelae with different members of the ingroup. Cladistic analysis using PAUP produced two equally parsimonious trees of 33 steps (CI = 0.758). Strict, Semistrict and Majority Rule consensus trees displayed the same topology. The phylogeny of the trees was not totally resolved. The bootstrap 50% majority-rule consensus tree supported, to a greater or lesser extent, the previously detected monophyletic groups. A common linkage for the ingroup was found in 72% of instances. The genus Euchelipluma appeared as monophyletic in 75% of instances while the group which included the genus Guitarra did so in 66%. The monophyly of the species with sigmoid microscleres and without spiny isochelae (G. isabellae/sigmatifera/antarctica/dendyi and C. diatomorpha/massa ) received 56% support as did the group of species with spiny isochelae, whereas monophyly of the group laplani/ bipocillifera received 64% support and the genus Tetrapocillon 56%. According to our cladistic analysis, all the species bearing placochelae or derived forms should be allocated to Guitarridae. Within this family, the genus Euchelipluma appeared as monophyletic while Guitarra was paraphyletic. The single species of the genus Hoplakithara clearly belongs to the Guitarra ( sigmatifera ) group and thus becomes synonymous with Guitarra. G. solorzanoi is considered here a synonymy of G. laplani. A diagnosis for the 10 valid species of Guitarra known to date as well as for the two species of Coelodischela and the two of Euchelipluma is given.  相似文献   

10.
Two species of the genus Ponticulomyces collected from Japan for the first time are described and illustrated. Ponticulomyces kedrovayae is characterized by its lamellae staining yellow when bruised and in age, stipe lacking an annulus and a pseudorhiza, scattered pileal hairs, and large amygdaliform basidiospores. It mainly occurs on dead wood of Fagus crenata. Ponticulomyces orientalis is characterized by its scattered pileal hairs and broadly ellipsoid to ellipsoid basidiospores. It was collected mostly on dead wood of Cameria japonica.  相似文献   

11.
Ana Riesgo 《Tissue & cell》2010,42(3):198-201
During spermatogenesis of the carnivorous sponge Asbestopluma occidentalis, follicle cells that lined the spermatocysts phagocytosed unreleased mature sperm. Such follicle cells are part of the complex envelope that limits spermatocysts of A. occidentalis, which is also comprised of a collagen layer, a thick layer of intertwined cells, and spicules. Follicle cells showed vesicles containing single phagocytosed spermatozoa within their cytoplasm. Additionally, lipids and other inclusions were observed within the cytoplasm of follicle cells. It is likely that follicle cells recapture nutrients by phagocytosing spermatozoa and use them to form lipids and other inclusions. Such sperm phagocytosis is usually performed in higher invertebrates and vertebrates by Sertoli cells that are located in the testis wall. While Sertoli cells develop a wide range of functions such as creating a blood-testis barrier, providing crucial factors to ensure correct progression of spermatogenesis, and phagocytosis of aberrant, degenerating, and unreleased sperm cells, sponge follicle cells may only display phagocytotic activity on spermatogenic cells.  相似文献   

12.
13.
Ichthyological Research - A new snailfish, Careproctus tomiyamai, is described on the basis of four specimens collected from Suruga Bay, Tosa Bay, and the Hyuga-nada Sea, southern Japan...  相似文献   

14.
15.
A new species of the family Liparidae, fulvous snailfish Careproctus fulvus sp. n., is described from the Novaya Zemlya Depression of the Kara Sea at a depth between 190 and 414 m. The species belongs to the group of slit-eyed Careproctus (longitudinally oval pupil, elongated lower lobe of the pectoral fin, and large urogenital papilla). The representatives of the species are characterized by fulvous coloration with orange spots, deep body, small teeth, and three radials in the pectoral girdle. The eggs are deposited into glass sponges Schaudinnia rosea (Rossellidae). Valvatophilia (commensalism with bivalves) and carcinophilia (reproductive commensalism with crab-like decapod crustaceans of the family Lithodidae) have been registered in the family Liparidae before, but spongiophilia are described for the first time. Egg deposition into glass sponges (Rossellidae) is known also for cod icefishes (Nototheniidae) from Antarctic waters. Reproductive commensalism between the representatives of the family Liparidae in the Arctic, the species of the family Nototheniidae in the Antarctic, and glass sponges represents a new finding of bionomic bipolarity (independent appearance of similar adaptations in unrelated groups of fishes in two polar regions of the earth). Based on the ecologo-ethological classification of fish reproduction, brood hiding Careproctus species belong to ostracophils, a group of fishes deposited the eggs into live animals.  相似文献   

16.
Halichondrida is a pivotal demosponge order of which the classification underwent major changes in the recent history. The monophyly of this order and its intra-ordinal phylogeny cannot be reliably determined on the basis of morphology. Here we present a 28Sr RNA gene tree of selected halichondrids, which supports the hypothesis of halichondrid non-monophyly and elucidates further inter-ordinal relationships. We enlarged the analysis by previously published sequences, discuss how previous analyses suffer from taxon bias and analyse the resulting phylogenetic implications. Most halichondrid families (in particular Axinellidae und Dictyonellidae) cluster polyphyletic and the molecular classification of several genera does not agree with the current (morphological) system.  相似文献   

17.
Bioassay-directed fractionation of South Pacific marine sponges of the genus Xestospongia has led to the isolation of a number of halenaquinone-type polyketides, including two new derivatives named xestosaprol C methylacetal 7 and orhalquinone 8. Chemical characterization of these two new compounds was achieved by extensive 1D and 2D NMR spectroscopic studies. Evaluation of anti-phospholipase A2, anti-farnesyltransferase and antiplasmodial activities of this series is presented and structure/activity relationships are discussed. Orhalquinone 8 displayed a significant inhibition of both human and yeast farnesyltransferase enzymes, with IC50 value of 0.40 μM and was a moderate growth inhibitor of Plasmodium falciparum.  相似文献   

18.
A previously undescribed haustorial mycoparasite of Mucorales was studied at the light-microscopic level, based on dural cultures with three hosts, Mucor hiemalis, Mortierella remanniana, and Cunninghamella elegans. Sporangial and zygosporic development of the parasite are described and illustrated, and salient features of the fungus are compared with those of Piptocephalis and Syncephalis. The new fungus appears more nearly related to Piptocephalis in possessing similar hyphal and haustorial characteristics, dichotomously branched sporangiophores, and a nearly identical form of zygospore. Like a few species of Piptocephalis, the fungus lacks a head-cell, and it forms branched merosporangia one or two terminally on ultimate branches of the sporangiophore. However, merosporangial development in the fungus is unique for the Piptocephalidaceae in that it proceeds by a process of sequential acropetal budding leading to the formation of a more or less highly branched, moniliform sporangiole. Sporangiospores mature simultaneously, are multinucleate, and are liberated by merosporangial disarticulation. Because of its distinctive merosporangium, the Japanese isolate is placed in a new genus and species, huzuhaea moniliformis.  相似文献   

19.
Specimens of a new genus and species of the stichaeid fish,Leptostichaeus pumilus, were collected from the Okhotsk Sea off Hokkaido in Japan. The present new genus and species clearly differs from all the other genera and species of the stichaeid fishes in the following characters: 3 or 4 pectoral fin rays; 10 or fewer caudal principal rays; 79–82 dorsal spines; no pelvic fin; last interneural spine supporting a single dorsal spine; infraorbital, occipital and lateral line canals absent; moderate size of dorsal spine shorter than eye diameter; membranes of dorsal and anal fins widely connected with caudal fin; a large black spot divided by a yellow band present just above gill cover.  相似文献   

20.
Lu Chen  Shuqiang Li  Zhe Zhao 《ZooKeys》2015,(541):41-56
One new genus of the spider subfamily Coelotinae, Flexicoelotesgen. n., with five new species is described from southern China: Flexicoeloteshuyunensissp. n. (female), Flexicoelotesjiaohanyanensissp. n. (male and female), Flexicoelotesjinlongyanensissp. n. (male and female), Flexicoelotespingzhaiensissp. n. (female), Flexicoelotesxingwangensissp. n. (male and female).  相似文献   

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