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1.
Lagenophrys novazealandae n. sp. occurs on the gills of Paranephrops zealandicus, a parastacid crayfish from New Zealand. The new species has the hemispheroidal lorica most common among members of its genus and is distinguished by its possession of large tubercles on the thickened edge of the anterior lip of the lorica aperture, a deep cleft in the left side of the lip's edge, and a ovoid to reniform macronucleus located in the right-hand part of the body. It is probable that an as yet unnamed species of Lagenophrys known to occur on another species of Paranephrops in New Zealand is distinct from L. novazealandae but phylogenetically related to it. Lagenophrys petila n. sp. occurs on setae of Parastacoides tasmanicus, a parastacid from Tasmania. The new species has an ovoid lorica tapering to a slender pseudostalk at the posterior end, a type of lorica possessed by only two other members of its genus that also attach to their host's setae. It is distinguished from the other ovoid species by the proportions of the lorica, the extreme shortness of the lips of the lorica aperture, and an ovoid macronucleus located in the right, anterior part of the body. Clefts in the lips of L. novazealandae and other members of Lagenophrys may function as points of flexure to allow the lips to bend in ways that accommodate interspecific differences in the size of the epistomial disk and its operation during suspension feeding.  相似文献   

2.
Four dorvilleid species new to science are described from intertidal and subtidal sandy sediments. For three of them new genera are erected: Coralliotrocha natans gen. et sp.n., Microdorvillea otagensis gen. et sp.n. and Pusillotrocha Åkessoni gen. et sp.n. One species represents the first record of the genus Pettiboneia from Australia, P. australiensis sp.n. Ophryotrocha minuta Levi, 1954 redescribed from Helgoland is transferred to a different genus, Arenotrocha gen.n. The present taxa belong to a morphological series of species with an increasing degree of neoteny in the family Dorvilleidae.  相似文献   

3.
Archimonocelis medusa sp. nov. is described from eastern Australia. The species is characterized by numerous (15–25) pharynges, as well as by details of sclerotized organs and karyotype. It is the first polypharyngeal marine flatworm known, and the first record of polypharyngy outside the Tricladida. Polypharyngy is interpreted as a disruption of the processes of pharyngeal induction and inhibition during development. Its possible adaptiveness is discussed.  相似文献   

4.
Four new species of the genus Minona Marcus, 1946 from eastern Australia are described. Minona proculvaginata sp. n., M. australis sp. n. and M. concharum sp. n. have four genital pores, and differ in details of the copulatory organs. The epidermis of these three species is unciliated in a ventral area around the male pore. Based on this synapomorphic feature, they are sister species. The karyotype of M. proculvaginata and M. concharum is described. Minona heronensis sp. n. is distinct from congeneric species on the basis of the size of its accessory stylet and copulatory organ, pore indices and karyotype. It is compared to numerous similar Indo-Pacific species. Additional data on the anatomy and karyology of M. beaglei Martens & Curini-Galletti, 1989 from N. Australia, are given. One specimen from Heron Island is tentatively attributed to M. dolichovesiculu Tajika, 1982 a species widely distributed in the Indo-Pacific. Its karyotype is given.  相似文献   

5.
A new species of freshwater triclad, Romankenkius libidinosus sp. nov. , is described from New South Wales, Australia. The species is characterized by a large adenodactyl and unique genito-intestinal connections, and represents the first record of the genus Romankenkius outside Tasmania. The taxonomic and phylogenetic implications of several morphological features of the new species are discussed in the light of a previous phylogenetic study.  相似文献   

6.
We examined the stomach contents of 121 New Zealand (NZ) sea lions ( Phocarctos hookeri ) caught by the squid fishery during the summer/autumn 1997–2006 around the Auckland Islands (51°S, 166°E). Dietary variation was assessed among juveniles, lactating females, nonlactating females and males, and between areas on the Auckland Islands shelf. The digested fraction of the contents consisted mostly of opalfish ( Hemerocoetes spp.) (50.1% by number [ N ], 4.7% by mass [ M ]), rattail ( Coelorinchus spp.) (12.0% N , 2.4% M ), arrow squid ( Nototodarus sloani ) (14.1% N , 17.9% M ), octopus ( Enteroctopus zealandicus ) (2.1% N , 27.8% M ), and red cod ( Pseudophycis bachus ) (3.8% N , 4.3% M ). Opalfish was found in greater proportions in the stomachs of females (lactating: 58.1% N , nonlactating: 62.4% N ) and juveniles (56.9% N ) than males (14.5% N ). Juveniles caught smaller opalfish and rattail than adults did. Over all classes, sea lions ate larger prey in the east than in the north of the Auckland Islands shelf. The common prey—arrow squid and rattail—constitute an abundant resource at the edges of the Auckland Islands shelf, where lactating NZ sea lions forage. Although these key areas are far from the rookeries and impacted by the squid fishery, they may provide the only reliable resource able to support the cost of benthic foraging behavior in the deepest diver of all otariids.  相似文献   

7.
Weathering of plastic bottles, bags, fishing line, and other products discarded in the ocean causes tiny fragments to break off. These plastic fragments may accumulate biofilms, sink, and become mixed with sediment, where benthic invertebrates may encounter and ingest them. Here we show that four species of deposit-feeding and suspension-feeding sea cucumbers (Echinodermata, Holothuroidea) not only ingest small (0.25 mm < maximum dimension < 15 mm) nylon and polyvinyl chloride (PVC) fragments along with sediment, but also ingest significantly more plastic fragments than predicted given the ratio of plastic to sand grains in the sediment. During four-hour feeding trials, holothurians ingested between 2- and 20-fold more plastic per individual than expected for PVC fragments, and between 2- and 138-fold more for nylon line. In addition, two species ingested 4 mm diameter PVC pellets. The ecological relevance of plastic ingestion was assessed in the laboratory by counting and characterizing small plastic particles discovered in sediment samples from the same field sites where our holothurians were collected. Substantial numbers of plastic fragments (105 to 214 fragments per liter of sediment) were found in samples from three different locations along the east coast of the U.S.A. In addition, plastic collected from the sediment from two of our field sites was analyzed for polychlorinated biphenyls (PCBs). Plastic from one site tested positive for Aroclor 1254 at a concentration of 0.0106 μg g-1. While the negative effects of macroscopic marine plastic debris on a host of organisms are well documented, ingestion of small plastic debris by a wide range of benthic organisms, including both primary and secondary consumers, has received little attention. Given that plastics readily adsorb PCBs and other organic pollutants in marine environments, ingestion of plastic from sediment may provide a heretofore-undescribed pathway of exposure for benthic marine invertebrates.  相似文献   

8.
9.
Abstract. Reproduction and development in 5 brittle stars: Ophiactis resiliens, Ophionereis fasciata, Ophiothrix caespitosa, Ophiothrix spongicola , and Ophionereis schayeri were investigated in a series of laboratory spawning and fertilization trials. Ophiactis resiliens spawned in 90% of trials, both spontaneously (in response to disturbance) and after temperature and light shock. Ophiothrix caespitosa and Ophiothrix spongicola spawned in 100% of trials, largely due to spontaneous gamete release. In contrast, Ophionereis fasciata and Ophionereis schayeri spawned in only 32% and 50% of trials respectively, and only in response to temperature and light shock. All 5 species required an aggregation of males and females for spawning and fertilization. The breeding periods of each species, estimated from the spawning trials, are reported. Eggs of Ophiactis resiliens, Ophionereis fasciata, Ophiothrix caespitosa , and Ophiothrix spongicola were 83 μm, 99 μm, 105 μm, and 128 μm in diameter, respectively, and all underwent planktotrophic development through an ophiopluteus. Eggs of Ophionereis schayeri were 241 μm in diameter and underwent lecithotrophic development through an armless bilateral larva that secondarily transformed into a radial vitellaria. The two Ophionereis species, with differing modes of development, provide an ideal opportunity to examine life-history evolution within a clade; however, these species were the most difficult to spawn. Ophiactis resiliens and the two Ophiothrix species spawned readily when they were visually mature at collection, and are thus useful species for developmental studies.  相似文献   

10.
11.
Abstract

Oribotritia contortula n. sp., O. contraria n. sp., O. teretis n. sp., Rhysotritia bifurcata n. sp., Microtritia contraria n. sp., M. glabrata n. sp., Hoplophthiracarus bisulcus n. sp., Austrophthiracarus pulchellus n. sp., and Notophthiracarus claviger n. sp. are described from New Zealand.

The genera of Oribotritia Jacot, Rhysotritia Märkel & Meyer, Hoplophthiracarus Jacot, and Austrophthiracarus Balogh & Mahunka are new records for New Zealand.  相似文献   

12.
Two new Rhabdocoel species from the Peruvian Amazonia are described: Sergia calae n. sp. (Dalyelliidae) and Mesostoma ucamara n. sp. (Typhloplanidae). Both species were captured in the Pacaya-Samiria National Park, Loreto, Peru, with plankton-nets dragged several times through the abundant littoral floating plant-community. This is the first record of micro-turbellarians in this region. The discovery of these new species in the Pacaya-Samiria National Park suggests the high diversity of this area, which up to now has remained largely unknown, increases the general knowledge of the fauna of Neotropical turbellarians.  相似文献   

13.
Two new species of Dalyellidae, Dalyellia callvucurai n. sp. and Gieysztoria namuncurai n. sp., are described from temporary freshwater environments in central Buenos Aires Province, Argentina. The ultrastructure of the stylets of both species is also described. The new species of the genus Dalyellia is the second species of the genus found in the neotropics and the first whose stylet has been studied with scanning electron microscopy. Gieysztoria namuncurai n. sp. joins the seven species of the genus known in Argentina. The ultrastructural characteristics of the stylet place it in the Inaequales group, with complex stylets.  相似文献   

14.
The importance of taking into account parallelisms in the evolution of morphological characters is analyzed for the taxonomy of the class Holothuroidea. The establishment of the order Dactylochirotida and classification of the order Elasipodida serve as examples to illustrate insufficient appreciation of parallelisms in Holothuroidea. The following characters, evolving independently in different groups of sea cucumbers, are considered: a stout skeleton, reduction of the calcareous ring and the body wall sclerites; similarity of body shape; similarity in the shape of tentacles; reduction in the number of tentacles from 12 to 10 in different fam-ilies and subfamilies of the order Synaptida. Based on the analysis of morphological and molecular data, the family Deimatidae is transferred from the order Elasipodida to the order Aspidochirotida. It is hypothesized that the concave cup-shaped sclerites with three to five rays occurring in the family Laetmogonidae (order Elasipodida) are of paedomorphic origin and correspond to the early growth stages of the laetmogonid wheels; the concave cross-shaped sclerites of the families Elpidiidae and Psychropotidae may have originated from laetmogonid concave cup-shaped sclerites. Emended diagnosis of the order Elasipodida is proposed. The family Vaneyellidae previously synonymized by the author with the family Cucumariidae is reestablished, and its emended diagnosis is also proposed.  相似文献   

15.
《新西兰生态学杂志》2011,33(2):106-113
Figure of Eight Island is located in the southern end of the Auckland Islands and hosts the smallest breeding colony of New Zealand (NZ) sea lions (Phocarctos hookeri). Between 1995/96 and 2005/06, pup production in this colony decreased by 57% (from 144 to 62 pups). In contrast, there was a 30% decrease in pup production in the largest colony in the north-east of the Auckland Islands over the same period. NZ sea lions in the Auckland Islands area are subject to by-catch deaths and resource competition from subantarctic trawl fisheries. The present study investigated where four lactating females from Figure of Eight Island foraged during the austral summer of 2007/08 and compared their foraging areas with female NZ sea lions from the northern Auckland Islands breeding locations (Enderby and Dundas islands) and with fisheries activities. Females foraged south of Adams Island (the southernmost Auckland Island), predominantly at the edge of the Auckland Islands shelf, but those from Figure of Eight Island made shorter foraging trips within more concentrated areas than females from Enderby or Dundas islands. The 59 female NZ sea lions satellite-tracked to date from Figure of Eight, Enderby and Dundas islands foraged over the entire area of the Auckland Islands shelf and many (including three of the four females from Figure of Eight Island) had extensive overlap with subantarctic trawl fisheries. Further research is needed to determine whether the foraging behaviour of females from Figure of Eight Island is linked to their greater decline in pup production.  相似文献   

16.
17.
Abstract

Seven new taxa of marine mites (Halacaridae) are described from the marine littoral zone of northern and southern New Zealand: Agauopsis novaezelandiae, A. luxtoni, Halacarellus lubricus, Copidognathus lubricus, Simognathus glaber, S. glareus, and Rhombognathus novaezelandicus. A list of halacarid species known from New Zealand waters is added.  相似文献   

18.
The Far Eastern sea cucumber, Stichopus japonicus, is a favored food in Eastern Asia, including Korea, Japan, and China. Aquaculture production of this species has increased because of recent declines in natural stocks and government-operated stock release programs are ongoing. Therefore, the analyses of genetic structure in wild and hatchery populations are necessary to maintain the genetic diversity of this valuable marine resource. In addition, given that sea cucumber color affects market price, with the rare, possibly reproductively isolated, red type being the most valuable, an understanding of the genetic structure and diversity in color variation of green and red types is necessary. We analyzed the genetic structure of wild and hatchery-produced green type S. japonicus from Korea and China, and wild red type from Korea using 9 microsatellite makers. The number of alleles per locus ranged from 11 to 29 across all populations. The mean allele numbers of the green types from Korea (10.6) and China (10.1) were similar, but differed slightly from that of the red type (9.1). Pairwise multilocus F(ST) and genetic distance estimations showed no significant differences between the green types from Korea and China, whereas the differences between the green and red types were significant. This was clearly illustrated by a UPGMA dendrogram, in which the two close subclusters of green types were completely separated from the red type. In addition, the allele frequencies of the green and red types were significantly different. Assignment tests correctly assigned 100% (quality index 99.97%) of individuals to their original color types and demonstrated the feasibility of microsatellite analysis for discrimination between color types.  相似文献   

19.
Abstract

Three species of anglerfish, Histrio histrio, Antennarius ocellatus, and A. nummifer, are newly recorded from northern New Zealand waters. A. tridens is redescribed, and variations in its colour pattern are illustrated.  相似文献   

20.
Hox genes form a multigenic family that play a fundamental role during the early stages of development. They are organised in a single cluster and share a 60 amino acid conserved sequence that corresponds to the DNA binding domain, i.e. the homeodomain. Sequence conservation in this region has allowed investigators to explore Hox diversity in the metazoan lineages. Within parasitic flatworms only homeobox sequences of parasite species from the Cestoda and Digenea have been reported. In the present study we surveyed species of the Polyopisthocotylea (Monogenea) in order to clarify Hox identification and diversification processes in the neodermatan lineage. From cloning of degenerative PCR products of the central region of the homeobox, we report one ParaHox and 25 new Hox sequences from 10 species of the Polystomatidae and one species of the Diclidophoridae, which extend Hox gene diversity from 46 to 72 within Neodermata. Hox sequences from the Polyopisthocotylea were annotated and classified from sequence alignments and Bayesian inferences of 178 Hox, ParaHox and related gene families recovered from all available parasitic platyhelminths and other bilaterian taxa. Our results are discussed in the light of the recent Hox evolutionary schemes. They may provide new perspectives to study the transition from turbellarians to parasitic flatworms with complex life-cycles and outline the first steps for evolutionary developmental biological approaches within platyhelminth parasites.  相似文献   

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