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1.
Monitoring trips were conducted along the coast of the state of Rio Grande do Sul, Brazil from July 1997 to July 1998 to contribute
toward knowledge on the feeding habits of Fulmarus glacialoides during migration. Five hundred and sixty two carcasses of F. glacialoides were found, 42 of which were in adequate conditions for collection and subsequent stomach content analysis. All stomach revealed
the remains of cephalopods. The following were identified from the 60 lower beaks of cephalopods found: Sepidae, Histioteuthis sp., Discoteuthis sp., Chiroteuthis sp., Mesonychoteuthis hamiltoni, Lycoteuthis sp., Lycoteuthis lorigera, Ancistrocheirus lesueuri, Alluroteuthis antarctica, Loligo plei and Argonauta nodosa. Histioteuthis sp. was found in 70% of stomachs analyzed, with a mean biomass of 53 g. Fish were identified through otoliths and were found
in the stomach contents of two specimens. Elytra from insects were found in the contents of eight stomachs, at least 20 of
which were coleopterans. A Belostomatidae was found in the contents of one stomach. 相似文献
2.
Lake Edward, East Africa, harbours a largely understudied assemblage of haplochromine cichlids that displays a range of adaptions to various specialised trophic niches. In this system, we discovered specimens of Haplochromis with morphologies similar to those of oral-mollusc shellers from Lake Victoria. These morphologies are characterised by short oral jaws with stout teeth that are used either to crush molluscs or to grab the soft bodies of snails and wrench them out of their shells. A morphometric study on 47 specimens from Lake Edward revealed the presence of three new species with an oral-shelling morphology: Haplochromis concilians sp. nov., H. erutus sp. nov. and H. planus sp. nov. All three species are formally described. Stomach-content observations confirmed an opportunistic oral-shelling ecology for H. concilians sp. nov. and H. erutus sp. nov. Within H. planus sp. nov., only large specimens displayed a specialised oral-shelling morphology, but their stomachs were nearly empty, while small specimens consumed mainly Ostracoda and Hydrachnidia. Remarkably, the three species differed considerably in morphology from each other, but they each resembled oral-sheller species from Lake Victoria. 相似文献
3.
Alexander Glass 《Pal?ontologische Zeitschrift》2006,80(1):68-87
Four genera and species of protasterid ophiuroids have been reported from the Lower Devonian Hunsrück Slate:Bundenbachia beneckei, Palaeophiomyxa grandis, Mastigophiura grandis, andPalaeophiura simplex. In addition, the speciesMiospondylus rhenanus has traditionally been recognized as a member of the Lapworthuridae, a group of ophiuroids with paired but unfused ambulacrals. This ambulacral arrangement would make it unique among Hunsrück Slate ophiuroids.Palaeophiura simplex andM. rhenanus were originally based on Single, poorly preserved specimens, and their morphology has remained poorly understood. A restudy of the type material offP. simplex andM. rhenanus and a detailed comparison to other Hunsrück ophiuroids warrants reassignment of these taxa toBundenbachia beneckei.Palaeophiura simplex is a juvenile example of this species andM. rhenanus is a peculiarly preserved adult. A newly prepared, well-preserved specimen ofBundenbachia beneckei expands our knowledge of the morphology of its mouthframe. In addition,Mastigophiura grandis is revised and redescribed based on newly recognized fossil material. 相似文献
4.
The purple globe crab, Randallia ornata (Randall, 1839) (Decapoda: Leucosiidae) is a common crustacean found on sandy beaches from Northern California to Baja California, Mexico. An undescribed species of Carcinonemertes, which shares biological features with a partially described worm from Tasmania was recovered from R. ornata. The worm reaches 10 mm in length and secretes a sturdy tube with a distinctive spiral shape. The total prevalence of the worm on R. ornatawas 70% (85% for ovigerous female crabs, 67% for post-ovigerous female crabs, and 45% for male crabs). Intensities reached 32 worms per crab. Adult worms were found in crab egg masses, regressed adults were recovered from under the abdomen of post-ovigerous females, and encysted juveniles were found on the gill lamellae of non-ovigerous female crabs and occasionally from the gill lamellae of male crabs. 相似文献
5.
E. Deslandes P. Pondaven T. Auperin C. Roussakis C J. Guézennec V. Stiger C. Payri 《Journal of applied phycology》2000,12(3-5):257-262
An unusual sulfated fucan-like polysaccharidecontaining aminosugar constituent was isolated fromthe brown Fucales, Turbinaria ornata. Itsantiproliferative effect on asynchronous cells of ahuman non-small-cell bronchopulmonary carcinoma line(NSCLC-N6) was studied in vitro. The kinetics ofcell growth further to the continuous exposure ofcells to T. ornata extract was investigated andthe changes in the cell cycle were observed usingflow-cytometry. Cell growth appeared to be inhibitedin the G1 phase. Altogether our observations suggesta triggering of the terminal differentiation ofcancerous cells by this fucan-like polysaccharide. 相似文献
6.
Klervi Le Lann Edouard Kraffe Nelly Kervarec Stéphane Cerantola Claude Elisabeth Payri Valérie Stiger‐Pouvreau 《Journal of phycology》2014,50(6):1048-1057
Several species of the genus Turbinaria coexist along the coasts of islands in the Indian and Pacific Oceans. Among these brown algae, Turbinaria ornata and T. conoides are sister species that are difficult to differentiate using exclusively morphological characters. Based on in vivo nuclear magnetic resonance and chromatographic techniques, i.e., liquid and gas chromatography‐mass spectrometry analysis, combined with phylogenetic data, we successfully identified turbinaric acid in T. conoides samples from several Indian and Pacific Ocean islands. This nonvariable discriminant molecule was only identified in T. conoides specimens, but not in the two allied species T. ornata and T. decurrens. Results are discussed with regard to turbinaric acid as an interesting chemomarker isolated from T. conoides and the rapid discrimination of Turbinaria specimens using chemical assays. 相似文献
7.
Morphological and anatomical evidence is presented to support the taxonomic judgment that Talarodictyon tilesii Endlicher is conspecific with Hydroclathrus stephanosorus Kraft in Kraft & Abbott. Because the former name has nomenclatural priority over the latter name, Hydroclathrus tilesii (Endlicher) comb. nov. is proposed. 相似文献
8.
Francesco P. Nicoletti Matthew K. Thompson Stefan Franzen Giulietta Smulevich 《Journal of biological inorganic chemistry》2011,16(4):611-619
Dehaloperoxidase-hemoglobin (DHP) is a unique multifunctional enzyme with a globin fold. The enzyme serves as the respiratory
hemoglobin for the marine worm Amphitrite ornata and has been shown to catalyze the conversion of highly toxic trihalophenols to dihaloquinones as a detoxification function
for the organism. Given the simplicity of the structure of A. ornata, it is entirely possible that DHP may play an even more general role in detoxification of the organism from sulfide commonly
found in the coastal estuaries where A. ornata thrives. Comparison of DHP with other sulfide-binding hemoglobins shows that DHP possesses several distal cavity structural
properties, such as an aromatic cage and a hydrogen-bond-donor amino acid (His55), that facilitate sulfide binding. Furthermore,
a complete reduction of the ferric heme occurs after sulfide exposure under aerobic or anaerobic conditions to yield either
the oxy or the deoxy ferrous states of DHP, respectively. Oxidation of sulfide by the heme leads to sulfur products that are
less toxic to A. ornata. This proposed new function for DHP relies on the highly flexible distal His55 for deprotonation of the bound hydrogen sulfide,
similar to H2O2 activation of the peroxidase function, and provides further support for the importance of the flexibility of the distal His55
in this novel globin. 相似文献
9.
The somatic and meiotic chromosomes of the South American leptodactylid toads Odontophrynus americanus, Ceratophrys ornata, and C. cranwelli were analysed both with conventional staining and differential banding techniques. The karyotypes of O. americanus were tetraploid; those of C. ornata octaploid. Ceratophrys cranwelli is a diploid species whose karyotype displays great similarities with that of C. ornata. The high frequency of multivalent pairing configurations in the meioses of O. americanus and C. ornata indicate that these animals were of autopolyploid origin. The conventionally stained somatic chromosomes of O. americanus can be arranged into sets of four similar chromosomes (quartets); those of C. ornata, into sets of eight similar chromosomes (octets). The banding patterns revealed heterogeneity within some quartets of O. americanus, dividing each of them into two pairs of homologous chromosomes. In analogy, some octets of C. ornata can be subdivided into two quartets of chromosomes with homologous bands. These structural heterogeneities within the quartets and octets are interpreted as a diploidization of the polyploid karyotypes. Diploidization leads to genomes that are polyploid with respect to the amount of genetic material and diploid with respect to chromosomal characteristics and the level of gene expression. In tetraploid O. americanus, the number of nucleolus organizer regions (NORs) and their DNA content is proportional to the degree of ploidy. In contrast, up to eight NORs have been deleted in the octoploid C. ornata. These NOR losses are discussed as a possible reason for the reduction of genetic activity in polyploid genomes.This paper is dedicated to Prof. Dr. Hans Bauer on the occasion of his 80th birthday 相似文献
10.
Maria Virginia Petry Vanda Simone da Silva Fonseca Angelo Luís Scherer 《Polar Biology》2007,30(3):321-325
The black-browed albatross, Thalassarche melanophris, travels along the southern coast of Brazil during migration. Their numbers appear to have decreased in recent years. From
July 1997 to 1998, we carried out monthly surveys on the coast of Rio Grande do Sul, Southern Brazil, to count albatrosses
in the area and identify ingested items. We found 85 dead specimens of T. melanophris, from which 35 stomachs were collected and the contents analyzed. Nearly 6% of the stomachs contained fish, 32% contained
cephalopods and 9% contained crustaceans. About 69% of the stomachs contained nematodes and nematomorphs. The highest abundance
values found per stomach was 182 nematode individuals and 223 nematomorph individuals. Synthetic materials were present in
29% of the stomachs analyzed, comprising thermoplastic, nylon, rubber and metal wire. 相似文献
11.
Continuing study on the Chinese species of Phygasia Chevrolat, 1836 revealed 10 specimens collected from Taiwan that were distinctly different from other described species within
this genus. The new species is similar to P. ornata Baly, 1876 and P. pseudornata Wang et Yang, 2008, but can be distinguished from them by the color and position of elytra markings as well as the shape
of male genitalia: the black markings on the elytra only covered the humeral area and the sub-apical area of elytra, and genitalia
of male pointed and short with big basal opening. A new species, Phygasia taiwanensis sp. n., is described herein. 相似文献
12.
Uwe Fritz Heiko Stuckas Mario
Vargas‐Ramírez Anna K. Hundsdörfer Jérôme Maran Martin Päckert 《Journal of Zoological Systematics and Evolutionary Research》2012,50(2):125-136
We analyse phylogeny, systematics and biogeography of slider turtles (Trachemys spp.) using sequence data of four mitochondrial genes (3242 bp) and five nuclear loci (3396 bp) of most South American and southern Central American taxa and representatives of northern Central American, West Indian and North American slider species (16 species and subspecies) and allied North American species (genera Chrysemys, Deirochelys, Graptemys, Malaclemys, Pseudemys). By applying maximum likelihood, relaxed molecular clock and ancestral range analyses, we provide evidence for two successive colonizations of South America by slider turtles. In addition, we show that the current species delineation of Central and South American slider turtles is incorrect. Our data suggest that Trachemys grayi is a distinct polytypic species that embraces, besides the nominotypical subspecies, T. g. emolli and T. g. panamensis. Trachemys ornata is also polytypic with the subspecies T. o. ornata, T. o. callirostris, T. o. cataspila, T. o. chichiriviche and T. o. venusta. Moreover, T. adiutrix should be regarded as a subspecies of T. dorbigni. All studied Trachemys species are inferred to have originated in the Late Miocene to Early Pliocene. The ancestor of the two subspecies of T. dorbigni colonized South America most probably prior to the establishment of the land bridge connecting Central and South America, whereas the two South American subspecies of T. ornata represent a younger independent immigration wave from Central America. 相似文献
13.
Ophiuroidea is the most speciose of all classes of Echinoderma. It is an important component in benthic ecosystems, occurring in almost all ecological niches of modern seas. To date, the phylogeny and complete evolutionary history of the ophiuroids have not yet been fully resolved. In this study, we sequenced the complete mitochondrial genomes (mitogenomes) of Ophiothrix (Ophiothrix) exigua and two deep-sea species Histampica sp. CS049 and Ophioplinthaca sp. M5261. These two deep-sea ophiuroids displayed reversed strand-compositional bias and rearranged gene orders. Thirteen distinct patterns of mitochondrial gene order among ophiuroid mitogenomes were detected, with two gene order newly found in Ophiuroidea. Our data supported the gene order found in all sampled Ophiuridae as the most likely ancestral order of all Ophiuroidea. To improve phylogenetic accuracy based on nucleotide differences, two different criteria were used for the analyses: (i) nucleotide sequence from all codon positions (PCG123); (ii) the NTE method (“Neutral Transitions Excluded”) for ameliorating the misleading effects of a reverse strand bias in the data. The two methods confirmed the polyphyly of the orders Ophiacanthida and Amphilepidia. At family and genus level, Ophiuridae, Ophionotus and Ophioplinthus were not monophyletic. The most notable exception was that the NTE phylogeny showed low variation of branch length. NTE dataset generated younger age for most lower-level nodes than that from PCG123 dataset. All analyses suggested that the ophiuroids radiation occurred around the Permian–Triassic mass extinction event, and the divergence time of the deep-sea lineages was during the Cretaceous. 相似文献
14.
We analysed the diet composition of 133 specimens of the Worm Lizard, Diplometopon zarudnyi, in Riyadh province, Saudi Arabia. Analysis of stomach contents revealed that 90 specimens (66.6%) had prey items in their gut. The stomach content consisted mainly of small invertebrate prey (beetles), mainly larvae of Dermestes sp., but also imagines of Dermestes maculatus and Rhynchophorus ferrugineus. Dermestes sp. constitutes over 99% of the total food items, showing a high selectivity in food intake. The high number of beetles in the stomach contents indicates that this lizard forages very frequently. Specimens collected during winter had empty stomachs. The high proportion of fossorial prey items and the occasional records of other stomach contents show that D. zarudnyi only occasionally forages on the surface. 相似文献
15.
BEN THUY 《Palaeontology》2011,54(1):215-233
Abstract: Two new genera and species of ophiuroid, Inexpectacantha acrobatica new gen. et sp. and Eirenura papillata new gen et sp., are described on the basis of 39 articulated specimens and several hundreds of arm fragments and isolated skeletal parts. The material was extracted from a lumachellic bed in a late early Pliensbachian succession of argillites at Sedan, French Ardennes. The material is unusually well preserved with even finest structures of the skeleton discernible. Despite the exceptionally detailed morphological data extractable from the material, the higher taxonomic classification in the system of recent ophiuroids could only be tentatively attained. Inexpectacantha acrobatica seems best placed within the Ophioplinthacinae inside the Ophiacanthidae whereas Eirenura papillata shares greatest similarities with the Ophioleucinae. The occurrence of articulated specimens of different sizes, with some of the most delicate skeletal structures left intact, together with completely disarticulated skeletons of the same species suggests that the ophiuroids were preserved as autochthonous faunule among an in situ population of Modiolus sp. during a period of more favourable bottom water conditions in an otherwise largely hostile near‐shore soft‐bottom environment. Based on its small size, the highly flexible arms and the presence of well‐developed hooks on distal arm segments, an epizoic way of life is inferred for I. acrobatica while E. papillata, with its rigid arm structure and the conspicuously large tentacle pores, is interpreted as mostly deposit‐feeding bottom surface dweller. 相似文献
16.
There are several studies of neural development in various echinoderms, but few on ophiuroids, which develop indirectly via
the production of pluteus larvae, as do echinoids. To determine the extent of similarity of neuroanatomy and neural development
in the ophiuroids with other echinoderm larvae, we investigated the development of the nervous system in the brittle star
Amphipholis kochii (Echinodermata: Ophiuroidea) by immunohistochemistry. Immunoreactive cells first appeared bilaterally in the animal pole
at the late gastrula stage, and there was little migration of the neural precursors during A. kochii ontogeny, as is also the case in echinoids and holothuroids. On the other hand, neural specification in the presumptive ciliary
band near the base of the arms does occur in ophiuroid larvae and is a feature they share with echinoids and ophiuroids. The
ophiopluteus larval nervous system is similar to that of auricularia larvae on the whole, including the lack of a fine network
of neurites in the epidermis and the presence of neural connections across the oral epidermis. Ophioplutei possess a pair
of bilateral apical organs that differ from those of echinoid echinoplutei in terms of relative position. They also possess
coiled cilia, which may possess a sensory function, but in the same location as the serotonergic apical ganglia. These coiled
cilia are thought to be a derived structure in pluteus-like larvae. Our results suggest that the neural specification in the
animal plate in ophiuroids, holothuroids, and echinoids is a plesiomorphic feature of the Ambulacraria, whereas neural specification
at the base of the larval arms may be a more derived state restricted to pluteus-like larvae. 相似文献
17.
Ellen E. Faszewski Selsebil Sljivo Lisa Kriszun Jane C. Kaltenbach 《Journal of morphology》2014,275(1):51-56
Apoptosis (programmed cell death) occurs during normal development of anurans in organs such as gills, gut, and tail. For example, apoptotic cells have been reported in the luminal epithelium along the length of the digestive tract of both larvae and frogs; however, timing of the peak number of such cells varies in different species. The purpose of the present study was to ascertain whether apoptosis also varies by species during metamorphic restructuring of the skin (as larval epithelium is replaced by adult epidermis). To determine this, cross‐sections of dorsal skin from representative larval stages and frogs of Rana pipiens, R. catesbeiana, and Ceratophrys ornata were incubated with monoclonal antibody against active caspase‐3, one of the main enzymes in the apoptotic cascade. We observed apoptotic cells in the epidermis of the skin of the three species and found that such cells were more numerous in larval stages than in frogs and more abundant in the two ranid species than in C. ornata. These results contribute to our understanding of metamorphic changes in anuran skin. J. Morphol. 275:51–56, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
18.
Various aspects of reproduction were studied in three deep-sea octocorals belonging to the order Alcyonacea that co-occur
at bathyal depths on the continental edge and the slope of eastern Canada. The main goals were to expand knowledge of deep-water
heterotrophic corals and ascertain whether reproductive strategies could explain the known patterns of occurrence. Anthomastus grandiflorus is a gonochoric species with a female-biased sex ratio that exhibits internal fertilization and brooding of planula larvae.
Conversely, Primnoa
resedaeformis and Keratoisis ornata rely on broadcast spawning and external fertilization; their sexuality remains undetermined as spermatocysts were not found.
In P. resedaeformis, the presence of mixed size classes of oocytes in samples from all months, depths, and locations studied suggests continuous
oogenesis or overlapping development of oocyte cohorts, indicative of a gametogenic cycle spanning more than a year. No evidence
of periodicity was found in this species, although it could have been masked by the striking bathymetric variation in potential
relative fecundity (oocytes polyp−1). The two other octocorals displayed a clear annual breeding pattern. Spawning in K. ornata and larval release in A. grandiflorus occurred in late summer and fall, respectively, possibly in response to environmental factors, as supported by shifts in
the reproductive peak of A. grandiflorus across latitudes. The three species are presumed to share a nonfeeding larval mode, and data on their reproductive potential
do not present any striking disparities. Published data on bycatches and video surveys in Atlantic Canada indicate that the
gonochoric brooder A. grandiflorus is more widely distributed than the two free spawners, P. resedaeformis and K. ornata, which is contrary to common dispersal potential paradigms. 相似文献
19.
The preservation of non-mineralized tissues in the fossil record is extremely rare. The Lower Devonian Hunsrück Slate of Germany
has long been known for the preservation of non-mineralized tissues in pyrite but whether or not these remnants represent
true soft tissues has been questioned. This is especially true for struetures visible only on radiographs that are too delicate
for excavation by traditional methods. Here we report the discovery of well-preserved pyritized tube feet in six fully prepared
specimens of the protasterid brittle starBundenbachia beneckei from the Hunsrück Slate. This discovery represents the first report of fossilized ophiuroid tube feet in the fossil record.
The successful excavation of the delicate tube feet was made possible by improved airbrasive techniques developed by German
fossil collectors.
The relatively large size of the fossil tube feet inBunden-bachia beneckei is consistent with earlier inferences on size based on the presence of large podial basins. Protasterid ophiuroids lack the
specialized arm musculature and articulations that provide increased flexibility and strength to the arms of modern ophiuroids
with typically reduced tube feet. How-ever, tube foot form and perhaps function inBundenbachia might have been similar to those of living asteroids in which large tube feet are used primarily for locomotion and food-manipulation
thus compensating for a lack of specialized arm musculature and articulation. Hence, feeding and life mode of protasterid
ophiuroids was not necessarily limited to sedentary, infaunal microphagy as traditionally suggested.
Two Hunsrück protasterid ophiuroids,Bundenbachia benecki andPalaeophiomyxa grandis are redescribed and compared.
相似文献
20.
Austin M. Betancourt Ileana F. Fenwick Hunter B. Howard Alexys E. Long Peggy Fong Paul H. Barber Caitlin R. Fong 《Journal of phycology》2023,59(1):277-280
Coral reefs are shifting from coral to algal-dominated ecosystems worldwide. Recently, Turbinaria ornata, a marine alga native to coral reefs of the South Pacific, has spread in both range and habitat usage. Given dense stands of T. ornata can function as an alternative stable state on coral reefs, it is imperative to understand the factors that underlie its success. We tested the hypothesis that T. ornata demonstrates ontogenetic variation in allocation to anti-herbivore defense, specifically that blade toughness varied nonlinearly with thallus size. We quantified the relationship between T. ornata blade toughness and thallus size for individual thalli within algal stands (N = 345) on seven fringing reefs along the north shore of Moorea, French Polynesia. We found that blade toughness was greatest at intermediate sizes that typically form canopies, with overall reduced toughness in both smaller individuals that refuge within the understory and older reproductive individuals that ultimately detach and form floating rafts. We posit this variation in blade toughness reduces herbivory on the thalli that are most exposed to herbivores and may facilitate reproduction in dispersing stages, both of which may aid the proliferation of T. ornata. 相似文献