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1.
Both genders of Pseudocyclops schminkei n. sp. are described from a pearl fishery aquarium on Zamami Island, Okinawa, Japan; it is the 37th species of the genus. Pseudocyclops schminkei sp. nov. differs from other species of the magnus species group in the shape of the lobes of distal exopodal segment of the male left leg 5, and the morphology of setae on middle and distal exopodal segment of male right swimming leg 2. Aspects of the morphology of P. xiphophorus and P. bilobatus are redescribed, and an unnamed Pseudocyclops sp. from the Shedd Aquarium in Chicago, IL, is briefly noted. Females of P. schminkei sp. nov., P. xiphophorus and Pseudocyclops sp. could not be separated from each other with the small number of specimens available in this study for the former two species.  相似文献   

2.
Two new species of the kinorhynch genus Pycnophyes are described from the Atlantic Ocean, Northwest Spain, and the Mediterranean Sea, East of Spain, using differential interference contrast microscopy and scanning electron microscopy (SEM): Pycnophyes dolichurus sp. nov. and P. aulacodes sp. nov. Taxonomic characters from cuticular structures in homalorhagids are discussed and reevaluated. The longitudinal positions of cuticular structures along the trunk are furthermore defined, and the positional terminology is standardized. The distribution of the genus Pycnophyes in European waters is revised, revealing a poor knowledge of kinorhynch biogeography, probably due to incomplete sampling.  相似文献   

3.
One new kinorhynch genus and species and one new species from the genus Zelinkaderes are described from sandy sediment off Fort Pierce, Florida. The new genus and species, Tubulideres seminoli gen. et sp. nov. is characterized by the presence of the first trunk segment consisting of a closed ring, the second segment of a bent tergal plate with a midventral articulation and the following nine segments consisting of a tergal and two sternal plates. Cuspidate spines are not present, but flexible tubules are located on several segments, and in particular concentrated on the ventral side of the second segment. Middorsal spines are present on all trunk segments and are alternatingly offset to a position slightly lateral to the middorsal line. Zelinkaderes brightae nov. sp. is characterized by its spine formula in having middorsal spines on trunk segments 4, 6 and 8–11, lateroventral acicular spines on segment 2, lateral accessory cuspidate spines on segments 2 and 8, ventrolateral cuspidate spines on segments 4–6 and 9, lateroventral acicular spines present on segments 8 and 9, and midterminal, lateral terminal and lateral terminal accessory spines on segment 11. The spine formula of Z. brightae nov. sp. places it in a position in between Z. submersus and a clade consisting of Z. klepali and Z. floridensis. The new findings on Z. brightae nov. sp. have led us to propose an emended diagnosis for the genus.  相似文献   

4.
Investigations on calcareous dinoflagellates from surface sediments from the Mediterranean Sea revealed 14 species, including one new genus and four previously undescribed species: Calciodinellum levantinum sp. nov., Calciodinellum elongatum nov. comb., Lebessphaera urania gen. nov. et sp. nov., and Scripp‐ siella triquetracapitata sp. nov. Furthermore, Fuettererella cf. tesserula, so far only known from the fossil record, was found. The cyst–theca relationships of C. levantinum and C. elongatum are given, based on strains established from water samples of the Mediterranean Sea and the Atlantic Ocean. This study gives an insight into the importance of the modern Mediterranean Sea as an unique region concerning calcareous cyst producing dinoflagellates.  相似文献   

5.
The taxonomy of common northern nudibranch molluscs of the genus Dendronotus in the vast cold regions of Eurasia remains largely unknown. Abundant material collected in many localities from the Barents Sea, via the Arctic region, to the north‐west Pacific was analysed for the first time. An integrated approach combining morphological and ontogenetic data with molecular four‐gene (COI, 16S, H3, and 28S) analysis reveals seven species, including three previously undescribed. Dendronotus frondosus (Ascanius, 1774) and Dendronotus dalli Bergh, 1879 were commonly considered as amphiboreal species; however, according to this study they are restricted to the North Atlantic and the North Pacific, respectively. In the north‐west Pacific two new species were discovered, D endronotus kamchaticus sp. nov. and D endronotus kalikal sp. nov. , that are externally similar to D. frondosus, but that show significant distance according to molecular analysis and are considerably different in radular morphology. In the North Atlantic a new species D endronotus niveus sp. nov. , sibling to North Pacific D. dalli, is revealed. The separate status of North Atlantic Dendronotus lacteus (Thompson, 1840) is confirmed, including considerable range extension. The essential similarity of early ontogenetic stages of radular development common for species with disparate adult radular morphology (such as D. frondosus and D. dalli) is shown, and its importance for taxonomy is discussed. © 2015 The Linnean Society of London  相似文献   

6.
7.
  The Australian lizard, Egernia striolata, can distinguish its own scats from those of unfamiliar conspecific individuals. This appears to be unrelated to diet, because there is no difference in the response to scats from unfamiliar lizards fed on diets that are the same or different from the test lizard. The signal that induces the response is not a visual or tactile property of scat structure, because test lizards respond equally to crushed and intact scats. We suggest that a pheromone is secreted onto the scat as it is produced. Water solutions of scats did not contain signal components that allowed lizards to distinguish their own scats from others. However, solutions of scats in dichloromethane (DCM) retained unique characteristics, and test lizards responded more strongly to the solution from scats of an unfamiliar lizard that to the solution from their own scats. Further fractionation of the DCM solution in pentane and in methanol led to loss of the unique signals needed for individual recognition, but those were restored when the pentane and methanol fractions were recombined. We infer that these lizards can distinguish between scats of different individuals on the basis of signals they receive from a complex combination of chemicals. Received: 14 December 1998 / Received in revised form: 9 April 1999 / Accepted: 12 April 1999  相似文献   

8.
  An integrated biological effect monitoring concept has been tested in flounder (Platichthys flesus L.) from four locations with different anthropogenic impact in the German Bight. During 3 years of sampling, biomarkers at all levels of biological organisation from the molecular to the ecosystem level were applied and tested on 742 individual fish of body lengths between 18 and 25 cm. At the ecosystem level, the fish were taken as a habitat for the parasite assemblage. The hypothesis was that changes in the environment might lead to changes in the species diversity of parasites and in the infection intensity of single species, as well as between heteroxenic and monoxenic parasite species (H/M ratio). At the molecular level, activity of the CYP1A-dependent monooxygenase ethoxyresorufin O-deethylase (EROD) was used as a biomarker of exposure. At the subcellular level, the integrity of lysosomal membranes in hepatocytes was taken as an indicator of non-specific acute and chronic toxic effects. Both biomarkers are recommended by the ICES Advisory Committee on the Marine Environment for the application in biological effects monitoring programmes. In addition, neutral lipid content in the liver was used as a marker for pathologically induced fat accumulation. In the same individual fish, a new method for the measurement of macrophage aggregate activity in the liver was tested for its application and reliability in reflecting immunosuppression. Tests were accompanied by chemical analysis of standard organochlorine and heavy metal residues in flounder tissue. A total of 33 parasite species were found. As an indicator species, the mean abundance of Trichodina sp. reflected best the pollution gradient observed with highest infection intensity at the most polluted location. Species diversity was significantly higher in fish caught near the reference site and significantly lower in fish from the polluted Elbe estuary. The use of the heteroxenous/monoxenous species ratio as a marker was not useful at the locations investigated because of the dominance of heteroxenous species at all habitats. Since EROD activity and macrophage aggregate activity were dependent on sex and maturity of female flounder, only male fish were taken into consideration for the integrated evaluation of data. All biochemical and histochemical tests were able to reflect accurately the site-specific differences, as well as an observed pollution event at the end of 1995 as determined by chemical analyses. The correlation analysis revealed a connection not only between the single parasitological and biochemical parameters but also within these groups. The non-specific immune response and Trichodina infection intensity were correlated with all other parameters, leading to the assumption that these may serve as links between the lowest and the highest levels of biological organisation. The simultaneous use of metabolic and parasitological results facilitated the interpretation of the observed variations of the data and the distinction between natural variation and pollution-mediated effects. Received: 1 March 1999 / Received in revised form: 25 May 1999 / Accepted: 7 June 1999  相似文献   

9.
A new species of marine tardigrade is described coming from the muddy sediment of the Antarctic deep sea. Angursa antarctica sp. nov. is characterized by the presence of balloon-shaped primary clavae, long lateral cirri, long cephalic cirri, spines on legs I, hemispherical capsule-shaped papillae on legs IV, and short external peduncles. Geographical distribution of the genus Angursa extends to Antarctic waters, suggesting a cosmopolitan distribution for this bathyal and abyssal genus. A table comparing the main differentiating characteristics of the species of Angursa is presented. Received: 25 July 1997 / Accepted: 9 November 1997  相似文献   

10.
Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.  相似文献   

11.
Senecella calanoides Juday has been reported from fresh-water lakes of North America, Northern Siberia and inshore brackish waters of Kara and Laptev Seas. Investigation of 11 females and 2 males from the brackish waters of Neelov Bay (Laptev Sea) shows that second species, Senecella siberica sp. n., can be distinguished from S. Calanoides Juday by the greater size, a slightly asymmetrical female genital segment, the 3 external spines on the 3d exopod of 2 to 4th swimming legs and by more longer left endopod digitiform process of the male 5th legs. S. siberica seems to be brackish-water euryhaline species, inhabiting brackish waters with salinity from 1 to 22. The genus belongs to the family Aetideidae and is the only genus with freshwater representatives.  相似文献   

12.

Cucullanus tunisiensis sp. nov., (Nematoda: Cucullanidae), collected from the intestine of the white grouper Epinephelus aeneus from waters off the coast of Tunisia is described based on light and scanning electron microscopic observations. The new species is characterized by the presence of lateral alae, ventral sucker, long unequal spicules (left spicule 2474-2789 μm long, right spicule 2357-2518 μm long). This is the sixth nominal species of the genus Cucullanus Müller, 1777 and the first representative of this genus infecting fishes of Serranidae family reported from Tunisian waters.

  相似文献   

13.
The cottid genus Radulinopsis Soldatov and Lindberg is recognized as a valid taxon including two species, R. derjavini Soldatov and Lindberg and R. taranetzi sp. nov., both distributed in shallow waters around Hokkaido, Japan, and the Russian Far East. Radulinopsis taranetzi differs from R. derjavini in having an almost naked body, teeth on the prevomer, and higher meristic counts. Radulinopsis derjugini Soldatov is synonymized with R. derjavini. A key to species of Radulinopsis and related genera is given. Based on a cladistic analysis of 18 morphological characters, Radulinopsis is the sister group of the Japanese genus Astrocottus, and the monophyletic eastern North Pacific group comprising Radulinus plus Asemichthys is the sister group of the western North Pacific group of Radulinopsis plus Astrocottus. Triglops, having a wide distribution throughout the North Pacific and North Atlantic, is putatively the sister group of a monophyletic group including these four genera. Bolin's genus Radulinus (including Radulinopsis as a subgenus) and Taranetz's subfamily Radulinae (including only Radulinus and Radulinopsis) are polyphyletic and therefore invalid. Received: September 7, 1999 / Revised: April 28, 2000 / Accepted: August 29, 2000  相似文献   

14.
Cryothecomonas longipes Schnepf and Kühn sp. nov. is a colourless biflagellate organism, 9–14 μm long and 7–9 μm wide when not filled with food vacuoles. It was detected in the North Sea, feeding with pseudopodia on diatoms. It penetrates the host shell, while the main body of the flagellate remains outside the frustule. Cells are covered with a multilayered theca. The pseudopodium protrudes through a preformed slit in the theca. Each flagellum also emerges through a pit in which the theca forms a funnel of complex structure that girdles each flagellum. The anterior flagellum is 9–15 μm long and oriented forward; the ventral flagellum, posteriorly directed, is 20–24 μm long and bears fine hairs. The flagellar roots consist of microtubules that emerge at satellites around the basal bodies and run along the flagellar pits. In addition, the ventral flagellum is accompanied by a band of six microtubules. It is proximally attached to a small fibrillar band, which interconnects the basal bodies. Cryothecomonas longipes has two or three types of extrusomes which pierce the theca when discharged. Their mode of discharge is discussed. Microbody-like vesicles containing small tubules are closely associated with older digestion vacuoles. Cryothecomonas longipes is compared with other species of the genus and a diagnosis is given. Received: 4 March 1999 / Received in revised form: 28 July 1999 / Accepted: 30 August 1999  相似文献   

15.
Percolomonads (Heterolobosea) are aquatic heterotrophic flagellates frequently found in saline waters up to hypersaline environments. We isolated and cultivated seven strains of percolomonad flagellates from marine waters and sediments as well as from a hypersaline inland lake in the Atacama Desert. Morphological characterizations, comprising light and scanning electron microscopy, revealed only slight differences between the strains mainly limited to the cell shape, length of flagella, and length of the ventral feeding groove. Phylogenetic analyses of the 18S and 28S rDNA genes showed the formation of three fully supported clades within the Percolomonadida: the Percolomonadidae, the Barbeliidae fam. nov. and the Lulaidae fam. nov. We describe two new families (Barbeliidae fam. nov., Lulaidae fam. nov.), a new genus (Nonamonas gen. nov.), and five new species (Percolomonas adaptabilis sp. nov., Lula levis sp. nov., Barbelia pacifica sp. nov., Nonamonas montiensis gen. et sp. nov., Nonamonas santamariensis gen. et sp. nov.). Salinity experiments showed that P. adaptabilis sp. nov. from the Atlantic was better adapted to high salinities than all other investigated strains. Moreover, comparisons of our cultivation-based approach with environmental sequencing studies showed that P. adaptabilis sp. nov. seems to be globally distributed in marine surface waters while other species seem to be more locally restricted.  相似文献   

16.
The first exploration of the kinorhynch meiofauna in Portuguese marine waters has revealed the existence of two undescribed species of the cyclorhagid genus Echinoderes. In the present contribution we describe Echinoderes lusitanicus sp. nov. and Echinoderes reicherti sp. nov., both collected from subtidal regions of the coast of Algarve in the southernmost region of Portugal. Echinoderes lusitanicus sp. nov. is recognized by the presence of tubes on segment 2 in subdorsal and ventrolateral positions, on segment 5 in lateroventral positions, on segment 8 in lateral accessory positions, and on segment 10 in laterodorsal positions. Spines are present in middorsal position on segments 4 to 8, and in lateroventral positions on segments 8 and 9. The females have minute lateral terminal accessory spines. The second species, E. reicherti sp. nov., is characterized by tubes on segment 2 in subdorsal and ventrolateral positions, on segment 5 in lateroventral positions, and segment 8 in sublateral positions. In addition, the species possesses acicular spines in the middorsal position on segment 4, and in lateroventral positions on segments 6 to 9. Morphological aspects such as tube/spine pattern of the trunk or sexually dimorphic traits are discussed and compared with other Echinoderes species showing close resemblance.

http://zoobank.org/urn:lsid:zoobank.org:pub:79C25EEE-9064-46F8-95E2-EE493DC82185  相似文献   


17.
  The relationships between gonadal maturation and the expression of behavioral and morphological display characters in O. mossambicus was investigated and the possible role of androgens in the coordination of this process was evaluated using genital papilla size as a bioassay for androgen levels. Morphological and behavioral displaying characters were found to be correlated among themselves. The sexually dimorphic characters were correlated with gonad maturation and androgen levels, but not with the gonado-somatic index. Gonad maturation and androgen levels were closely related. Territoriality and other behavioral variables involved in reproduction were also correlated with gonad maturation and androgen levels. These data suggest that in O. mossambicus androgens play a mediating role between gonadal maturation and the expression of display characters, both morphological and behavioral. Received: 23 February 1999 / Received in revised form: 3 May 1999 / Accepted: 10 May 1999  相似文献   

18.
Sphaeralcyon shackletonisp. nov. and Sphaeralcyon scottisp. nov. are described and illustrated from material collected at the Scotia Sea and Weddell Sea on the Polarstern cruises ANT XIX/3 (ANDEEP-I), ANT XIX/5 (LAMPOS), and ANT XXI/2 (BENDEX). With the discovery of Sphaeralcyon shackletoni and S. scotti, three species are now known in the genus Sphaeralcyon, all them reported from the Southern Ocean. The diagnosis of the genus has been slightly modified to accommodate some of the characters of the new species.  相似文献   

19.
  Socialization, that is, the process of the integration of an individual into the social system and the acquisition of basic social traits, has been studied in a variety of vertebrate species. Deprivation experiments have shown that the lack of early affiliative relationships has negative long-term effects on social behaviour and reproduction. Most studies emphasized the importance of the mother-infant relationship. However, it soon became evident that peer relationships to like-aged conspecifics, such as siblings and unrelated juveniles of nearly the same age, are also important for socialization. Whether individuals, deprived of one of these important social components, are able to compensate for this lack is not known. Here I tested the hypothesis that in spectacled parrotlets (Forpus conspicillatus), singletons (i.e., those that grew up without siblings) were able to compensate for this social lack by establishing and strengthening other relationships. In spectacled parrotlets socialization depends on the formation of long-lasting sibling groups. However, singletons without nest mates are quite common (about 6%), both in captivity and in nature. In this study I analysed the affiliative interactions with other group members of five singletons in comparison to eight siblings, from fledging to the 36th week after fledging, within a group of adult and juvenile conspecifics. In contrast to siblings, the singletons prolonged the relationships with their parents. Then they established a ”host sibling group” with other like-aged individuals. All singletons became well integrated into the group and established exclusive pair bonds. It is concluded that juvenile singletons of spectacled parrotlets are able to compensate for the lack of siblings by the development of alternative socialization tactics. Received: 12 December 1998 / Received in revised form: 17 May 1999 / Accepted: 7 June 1999  相似文献   

20.
Three species of blind Amphipoda are recorded from anchihaline cave waters in the Galapagos Islands. One of these, Galapsiellus leleuporum (Monod, 1970) was previously know from the islands; the male is described for the first time. The other two belong to families with predominantly (though not exclusively) deep-sea members: Valettietta cavernicola sp. nov. (family Lysianassidae; and Antronicippe serrata gen. et sp. nov. (family Pardaliscidae). The genus Valettietta was not previously recorded from caves; it contained two abyssal species in the Atlantic, while a third species was recorded from the Pacific in a vertical haul between 0 and 5300 m. Antronicippe is closely related to Spelaeonicippe, a genus with two species known from anchihaline caves in the Canary Islands and the West Indies.  相似文献   

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