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1.
Holynski  Mária  Fiers  Frank 《Hydrobiologia》1994,292(1):41-51
Within the genus Mesocyclops the thermocyclopoides species-group is defined on the basis of the presence of spiniform armature on the maxillar coxa. Examination of nineteen, mainly Palaeotropical species of Mesocyclops and nine representatives of the closely related genus Thermocyclops revealed, that the coxal part of the maxillar syncoxa of the species recently unified in the thermocyclopoides group is adorned with distinct rows of big spinules on its frontal surface. This character, with only one known exception in South Indian M. cf. papuensis, is absent in other species of Mesocyclops and all the Thermocyclops studied here. These species have no spinules on the maxillar coxa at all or very tiny scattered ones.  相似文献   

2.
A new genus and species of deep-water zoarcid fish, Ericandersonia sagamia, is described on the basis of four specimens collected from Sagami Bay, Japan, at depths of 880–930 m. This species is placed in the subfamily Gymnelinae and is distinguished from all genera of gymnelines by the following characters: pseudosubmental crest present; frontals partially fused dorsally; parietals meeting in midline; pelvic fins absent; ventral ramus of posttemporal weak; postorbital head pores 5; pectoral-fin rays 14. The phylogenetic analysis (based on 42 morphological characters) indicates that its position is outside the highly modified (= advanced) genera Seleniolycus, Melanostigma, Puzanovia, Nalbantichthys, Opaeophacus, and Andriashevia.  相似文献   

3.
Parabrotula tanseimaru sp. nov. (Zoarcoidei: Parabrotulidae) is described from Sagami Bay, central Japan, as the second species of the genus. The new species is readily distinguished from the known species,P. plagiophthalma, by dorsal fin ray counts (44–50 vs. 37–43) and higher total vertebral counts (64–73 vs. 54–64).P. tanseimaru is viviparous, occurring in pseudoceanic meso-/bathypelagic depths and feeding primarily on copepods.  相似文献   

4.
Two new species of the freshwater cyclopoid genera Eucyclops are described, Eucyclops tziscao sp. n. and E. angeli sp. n. Both species belong to the serrulatus-group defined by morphological features such as: the presence of distal spinules or hair-like setae (groups N1 and N2) on frontal surface of antennal basis; the fourth leg coxa with a strong inner spine that bears dense setules on inner side, yet proximally naked (large gap) on outer side; and a 12-segmented antennule with smooth hyaline membrane on the three distalmost segments. Eucyclops tziscao sp. n. is morphologically similar to E. bondi and E. conrowae but differs from these species in having a unique combination of characters, including a caudal ramus 4.05±0.25 times as long as wide, lateral seta of Enp3P4 modified as a strong, sclerotized blunt seta, coxal spine of fourth leg with inner spinule-like setules distally, and sixth leg of males bearing a strong and long inner spine 2.3 times longer than median seta. Eucyclops angeli sp. n. can be distinguished by an unique combination of morphological features: the short caudal ramus; the long spine on the sixth antennular segment of A1; the presence of one additional group of spinules (N12’) on the caudal surface of A2; the presence of long setae in females, or short spinules in males on the lateral margin of fourth prosomite; the strong ornamentation of the intercoxal sclerite of P4, specially group I modified as long denticles; the distal modified setae of Exp3P3 and Exp3P4 in females and males; and the short lateral seta of P5. Finally, we report on a new record of E. festivus in México, and add data on morphology of the species.  相似文献   

5.
Cabillus atripelvicus is described from three specimens, 26.1–40.6 mm in standard length, collected from depth 17–29 m in the Ogasawara Islands. In addition, two small specimens taken by dredge in 50–55 m from Sagami Bay, Honshu, and one from Tachibana Bay, Kyushu, are identified as this species but not designated as paratypes. Cabillus atripelvicus is distinguished from the four other described species of the genus by its high count of 18–20 pectoral rays, presence of median predorsal scales, longer pectoral fins, and distinctive color pattern, including black pelvic fins. The range of C. lacertops Smith, 1959 is extended east to the Marshall Islands and that of C. tongarevae (Fowler, 1927) east to American Samoa. More species remain to be described in the genus. Supplementary material to this paper is available in electronic format at  相似文献   

6.
The generic composition of the heterotrophic bacterial population of Tokyo Bay, which is now highly polluted and eutrophic, was compared with that of the adjacent, less polluted regions of Sagami Bay and Suruga Bay. Members of Vibrionaceae predominated in the bacterial flora of seawater and zooplankton samples from Sagami Bay, Suruga Bay, and the mouth of Tokyo Bay. However,Vibrio spp. formed only a small proportion of the bacterial population of the water and sediment samples from the inner Tokyo Bay; there the Gram-negative, nonmotile, nonpigmented bacteria, which were tentatively identified asAcinetobacter, were predominant. The result of experiments, in which seawater samples from Tokyo Bay were incubated under various experimental conditions, indicated that two significant factors apparently control the growth ofVibrio spp. in seawater; (1) a direct antagonism betweenVibrios and phytoplankton undergoing rapid growth, and (2) a limiting organic nutrient forvibrios.  相似文献   

7.
Ichthyological Research - The pygmygoby Trimma albicaudatum sp. nov. is described on the basis of a single specimen (18.0 mm standard length) from Sagami Bay, Honshu, Japan. The new species can be...  相似文献   

8.
Ribautia williamsi sp. nov., a new dwarf geophilomorph centipede from the Lower Urubamba Region, Peruvian Amazonia, is described and illustrated based on the holotype female. The new species is characterized by having the coxal organs grouped in clusters (three of these in each coxopleuron of the ultimate leg-bearing segment) and ventral pore-fields present along all the body; these two combined traits being shared by five other Neotropical species currently included in the genus Ribautia Brölemann, 1909, i.e. R. centralis (Silvestri, 1907) (from Colombia and Brazil), R. difficilis Pereira, Minelli &; Barbieri, 1995 (from Brazil), R. montana Kraus, 1954 (from Peru), R. peruana (Verhoeff, 1941) (from Peru), and R. titicacae (Turk, 1955) (from Peru). The new taxon is differentiated from the aforementioned species by the low number of leg-bearing segments and small body length; it is included in a key which will enable the identification of all known Neotropical members having coxal organs grouped in clusters. R. williamsi sp. nov. is the 14th species of Ribautia recorded from Peru.

http://zoobank.org/urn:lsid:zoobank.org:pub:D9FA5FAF-7652-4A5B-AC09-8783F05A694D  相似文献   

9.
In an effort to broaden our understanding of the biodiversity and distribution of gregarines infecting crustaceans, this study describes two new species of gregarines, Thiriotia hyperdolphinae n. sp. and Cephaloidophora oradareae n. sp., parasitizing a deep sea amphipod (Oradarea sp.). Amphipods were collected using the ROV Hyper‐Dolphin at a depth of 855 m while on a cruise in Sagami Bay, Japan. Gregarine trophozoites and gamonts were isolated from the gut of the amphipod and studied with light and scanning electron microscopy, and phylogenetic analysis of 18S rDNA. Thiriotia hyperdolphinae n. sp. was distinguished from existing species based on morphology, phylogenetic position, as well as host niche and geographic locality. Cephaloidophora oradareae n. sp. distinguished itself from existing Cephaloidophora, based on a difference in host (Oradarea sp.), geographic location, and to a certain extent morphology. We established this latter new species with the understanding that a more comprehensive examination of diversity at the molecular level is necessary within Cephaloidophora. Results from the 18S rDNA molecular phylogeny showed that T. hyperdolphinae n. sp. was positioned within a clade consisting of Thiriotia spp., while C. oradareae n. sp. grouped within the Cephaloidophoridae. Still, supplemental genetic information from gregarines infecting crustaceans will be needed to better understand relationships within this group of apicomplexans.  相似文献   

10.
11.
Phylogenetic and morphological reinvestigation of Chondrus verrucosus Mikami was conducted in the Pacific coast of southeastern Honshu, Japan, including the holotype specimen and samples near the type locality. Two entities were recognized by phylogenetic analyses of plastid rbcL and nuclear EF2 sequences. In morphological analyses, the two entities were distinguished by: (i) thallus size and form, and (ii) cell shape of the medullary layer surrounding young carposporangia: one has larger thalli, is regularly canaliculated, with linear medullary cells (large‐type); the other is smaller, canaliculated with crispation and has roundish medullary cells (small‐type). The large‐type was common in southern to eastern Boso Peninsula including near the type locality; the small‐type was typical in the southwest Boso Peninsula and Sagami Bay. The large‐type was shown to be equivalent to C. verrucosus by examination of the holotype specimen. The small‐type is described as a new species, C. retortus Matsumoto et Shimada.  相似文献   

12.
《Journal of morphology》2017,278(11):1551-1569
Coxal glands of unfed larvae Leptotrombidium orientale (Schluger, 1948) (Trombiculidae), a terrestrial mite parasitizing vertebrates, and Hydryphantes ruber (de Geer, 1778) (Hydryphantidae), a water mite parasitizing insects were studied using transmission electron microscopy. In both species, the coxal glands are represented by a paired tubular organ extending on the sides of the brain from the mouthparts to the frontal midgut wall and are formed of the cells arranged around the central lumen. As in other Parasitengona, the coxal glands are devoid of a proximal sacculus. The excretory duct, joining with ducts of the prosomal salivary glands constitutes the common podocephalic duct, opening into the subcheliceral space. The coxal glands of L. orientale are composed of a distal tubule with a basal labyrinth, an intermediate segment without labyrinth, and a proximal tubule bearing tight microvilli on the apical cell surface and coiled around the intermediate segment. The coxal glands of H. ruber mainly consist of the uniformly organized proximal tubule with apical microvilli of the cells lacking the basal labyrinth. This tubule shows several loops running backward and forward in a vertical plane on the side of the brain. In contrast to L. orientale , larvae of H. ruber reveal a terminal cuticular sac/bladder for accumulation of secreted fluids. Organization of the coxal glands depends on the ecological conditions of mites. Larvae of terrestrial L. orientale possess distal tubule functioning in re‐absorption of ions and water. Conversely, water mite larvae H. ruber need to evacuate of the water excess, so the filtrating proximal tubule is prominent.  相似文献   

13.
The epidermal setae and the spinules of the digital lamellae of anoline and gekkonid lizards are shed periodically along with the rest of the outer layer of the skin. These structures are developed within the lamellae prior to ecdysis. The setae are larger and more complicated than the spinules and begin their development first. The setae of Anolis start as aggregations of tonofibrils beneath the plasma membrane of the presumptive Oberhautchen cells. These cells are arranged in rows parallel to the surface, several cell layers beneath the alpha layer of the skin. The developing setae protrude into the clear layer cells as finger-like projections, with the tonofibrils longitudinally oriented in the direction of growth. About 100 setae are formed by each Oberhautchen cells in Anolis. In late development, the clear layer cells lose their cellular contents and when shed along with all distal cells, retain a template of the new setae or spinules. The spinules and setae are formed before the fibrous and alpha layers of the new skin. The fibrous layer, which occurs only on the ventral (outer) layer of the lamellae, and the Oberhautchen with its setae and spinules, is considered the beta layer. The alpha layer, which occurs adjacent to the fibrous layer on the ventral surface and adjacent to the Oberhautchen on the dorsal (inner) surface, is morphologically identical to that of mammalian α keratin. The shed lizard skin consists of the alpha and beta layers as well as the degenerating cells of the outer epidermal generation, and the clear layer. The clear layer that is shed shows the template of the new setae and spinules developed in the new skin layer. The separation of the new from the old skin occurs along the intercellular space between the clear layer cells and the new Oberhautchen. The alpha layer of the skin is not fully keratinized at shedding. The setae of the digital lamellae of lizards represent unique epidermal structures — intracellular keratinized microstructures.  相似文献   

14.
Bomolochus peruensis n. sp., a parasite of the sciaenid fishes Menticirrhus ophicephalus and Sciaena deliciosa from the central Peruvian coast, is described and illustrated. The new taxon differs from all other Bomolochus species in a combination of characteristics of leg 2, leg 4 and leg 6 and by the presence of spinules on the ventral surface of the last abdominal segment only. This is the first record of Bomolochus from South America.  相似文献   

15.
Abstract

We describe a new skink species (Oligosoma taumakae sp. nov.) from the Open Bay Islands, New Zealand. This species is diagnosed on the basis of several morphological characteristics, and its specific status is supported by mitochondrial sequence data (ND2, ND4). The new species appears to be most closely related to O. acrinasum, O. infra‐punctatum, O. otagense and O. waimatense. The new taxon appears to be rare and endemic to the island of Taumaka in the Open Bay Islands (off the west coast of the South Island). Predation by a flightless rail (weka, Gallirallus australis), native to New Zealand but introduced to the Open Bay Islands, is a major conservation concern.  相似文献   

16.
In Sagami Bay, Japan, Leiosolenus curtus (Lischke, 1874) bores into dead shells of rock barnacles (Tetraclita japonica) in Manazuru, calcareous sand-rock in Oiso, weathered tuff in Miura and agglomerates formed by the tubes of clam worms (Spirobranchus kraussii) in Kanaya. In order to understand the relationships between morphology and environment, the shell morphologies and genetic characteristics of L. curtus, together with the calcium content of the different bored substrata, were analysed. Individuals from Kanaya and Manazuru were characterised by a chalk-like encrustation and a more rounded and inflated shell shape, while those from Oiso and Miura had a striated encrustation. The molecular phylogenetic tree and haplotype network showed that the genetic sequences of the individuals from all investigated localities were very similar, and implied that they belong to the same species. The striated encrustation of the individuals from Oiso and Miura presumably enables them to scrape those residues not dissolved by the mucus secreted by the mantle gland, and thereby to bore into non-calcareous substrata. The more rounded and inflated shell shape of the individuals from Manazuru is thought to be advantageous for boring into thin substrata.  相似文献   

17.
A new species of the genus Rhodotorula was isolated from a tubeworm (Lamellibrachia sp.) collected at a depth of 1156 m in Sagami Bay, Japan. Strain SY-89 had physiological properties quite similar to R. aurantiaca. Two phylogenetic trees, one based on internal transcribed spacer (ITS) regions and 5.8S rDNA sequences and the other based on the D1/D2 region of the large subunit (26S) rDNA sequences, united strain SY-89 to the type strain of Sakaguchia dacryoides through a considerable evolutionary distance. Strain SY-89 was differentiated from S. dacryoides by the G+C content of the nuclear DNA and differences in the ability to utilize specific carbon and nitrogen compounds. The low complementarity of strain SY-89 DNA to that of the type strain of S. dacryoides confirmed that this strain was genetically unrelated to previously known species. The tubeworm isolates are described as R. lamellibrachii sp. nov. The type strain of R. lamellibrachii is strain SY-89 (= JCM 10907). R. lamellibrachii formed a cluster with Erythrobasidium hasegawianum, R. lactosa, S. dacryoides and Sporobolomyces elongatus on the ITS and 5.8S rDNA phylogenetic tree. These five species shared a signature sequence in 26S rDNA, although this relationship was not supported by phylogeny based on the D1/D2 region of 26S rDNA.  相似文献   

18.
Fissarcturus bathyweddellensis sp. nov. and Fissarcturus sandwichi sp. nov. are described from the abyssal Southern Ocean near the Antarctic Peninsula and Fissarcturus rossi sp. nov. is described from the shallow Ross Sea. A list of all described species of Fissarcturus is given. The new species differ from recognized species of the genus in the following respects: F. bathyweddellensis can be distinguished based on spination on the dorsum of the body, which is described in detail herein. It is most similar to F. emarginatus Brandt, 1990, but this has, for example, a shorter and less stout second cephalic spine. F. rossi can also be distinguished from F. bathyweddellensis based on spine pattern. Whereas all dorsal spines of F. bathyweddellensis are smooth, those of F. rossi are covered with spinules. F. sandwichi can be distinguished from the other species of the genus by the strong frontally bent supraocular spines (females with second cephalic spines) and dorsal body surface, which is covered with flat, cauliflower-like elevations in submedial, lateral and coxal rows.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 263–290.  相似文献   

19.
The Phoronida is a phylum of marine invertebrates that have a worldwide distribution and that form huge benthic aggregations in many aquatic areas. Although there are only 11 recognized species of phoronids, many species clearly remain to be described. The matching of larval and adult stages of the same species will help indicate which larvae belong to described species and which represent undescribed species whose adults have yet to be found. Larvae of four phoronid species were collected in Nha Trang Bay and investigated by light microscopy and molecular methods. Three of the described larvae belong to new phoronid species that have yet to be named. These larvae have unique morphological features and occupy separate positions on the phylogenetic tree of phoronids. One of the described larvae belongs to Phoronis hippocrepia or to a closely related species. Observations made with a new macrophotographic method indicated that Phoronopsis californica also occurs in Nha Trang Bay. Thus, according to records of larvae and adults, Nha Trang Bay contains at least nine phoronid species: Phoronopsis californica, Phoronopsis malakhovi, Phoronis australis, Phoronis hippocrepia (or a closely related species), three unknown phoronid species whose larvae have unique morphological features and that apparently belong to the genus Phoronis, and two species, whose adults have unique set of morphological features. The richness of phoronids in this area suggests that the Indo-Pacific is a centre of phoronid biodiversity.  相似文献   

20.
We report successful larval hatching of deep-sea shrimp after decompression to atmospheric pressure. Three specimens of deep-sea shrimp were collected from an ocean depth of 1157 m at cold-seep sites off Hatsushima Island in Sagami Bay, Japan, using a pressure-stat aquarium system. Phylogenetic analysis of Alvinocaris sp. based on cytochrome c oxidase subunit gene sequences confirmed that these species were a member of the genus Alvinocaris. All 3 specimens survived to reach atmospheric pressure conditions after stepwise 63-day decompression. Two of the specimens contained eggs, which hatched after 10 and 16 days, respectively, of full decompression. Although no molting of the shrimp larvae was observed during 74 days of rearing under atmospheric pressure, the larvae developed conventional dark-adapted eyes after 15 days.  相似文献   

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