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1.
A new species of the Macrochironidae Humes & Boxshall, 1996 (Copepoda: Cyclopoida), Pseudomacrochiron aureliae n. sp., is described based on adult specimens extracted from the gastrovacular cavity of the scyphistomae of Aurelia sp. (Cnidaria: Scyphozoa) collected in the Seto Inland Sea and Ise Bay off the coast of Japan. The new species differs from its congeners by having the following combination of characters: a caudal ramus with a length to width ratio of 3.1; an accessory flagellum on caudal setae II, III and VI; three apical setae on the maxillule; only setae I and II on the maxillary basis; two short spines on the female maxilliped claw (endopod); an armature of III, I, 4 on the terminal exopodal segment of leg 3; an armature of I, II, 2 on the terminal endopodal segment of leg 3; an armature of II, I, 4 on the terminal exopodal segment of leg 4; and a short free exopodal segment of leg 5 (length to width ratio of 1.4) armed with a long seta and short spine. P. aureliae n. sp. is the first member of the genus reported from off Japan and from the scyphistomae of its scyphozoan host.  相似文献   

2.
In the course of a comparative analysis of the species included in the copepod genus Monstrillopsis Sars, a new species of the genus was discovered. The new species, Monstrillopsis chilensis n. sp., was found in a plankton sample collected in coastal waters off central Chile in the Southeastern Pacific. The adult female is similar to females of the type species M. dubia Scott and related forms but differs from its congeners by a combination of characters including: (1) a pair of small cephalic processes present between bases of antennules; (2) deep corrugations present on proximo-lateral surface of fifth pedigerous somite; (3) exopodal lobe of fifth leg not distally elongated; and (4) endopodal lobe of fifth legs short. This is the first record of the genus in the Southeastern Pacific and the second record of any monstrilloid in Chile. A comparative analysis of the species assigned to Monstrillopsis allowed a clarification of the generic characters and limits. The most important apomorphic characters in the genus are the presence of four caudal setae and modifications of the male antennule; other potentially useful characters are the pattern of antennule segmentation and the uniform presence of a reduced inner lobe of the fifth leg. The female of Monstrilla reticulata Davis should be retained in Monstrilla, but the purportedly conspecific male is probably a Monstrillopsis. Monstrillopsis ciqroi Suárez-Morales and M. angustipes Isaac should be transferred to Monstrilla. Haemocera filogranarum Malaquin is probably a species of Monstrillopsis. Monstrillopsis zernowi is tentatively retained in this genus as an aberrant form. A key for the identification of the species of this genus is included.  相似文献   

3.
A new species of Acartia (Copepoda, Calanoida) from the Yellow Sea   总被引:2,自引:0,他引:2  
A new species (Acartia hongi) of Acartia (family Acartiidae)predominating in the Korean coastal waters of the Yellow Seais described. This species closely resembles Acartia bifilosa,from which it can be easily distinguished by the co-occurrenceof the following morphological characters: the absence of rostralfilaments in both genders; the terminal spine on the femalefifth leg toothed only on the inner side; the first exopodalsegment of the male right fifth leg with a long seta; the distalsegment of the male left fifth leg with a rod-like appendage.Its distribution was discussed in comparison with two siblingspecies, Acartia omorii and Acartia hudsonica.  相似文献   

4.
The Cypricercinae are one of the most speciose subfamilies of non-marine ostracods, with more than 170 described species, mostly from the tropics. Although the identity of the subfamily as such is clear, because of the presence of unifying characters such as the Triebel’s loop in the attachment of the caudal ramus, the supra-specific taxonomy of this group has long been confused because of lack of good generic and tribal characters. Here, the generic characters of the Cypricercinae are revised. Eleven genera are retained in this subfamily, including three new genera: Bradleytriebella n. gen., Nealecypris n. gen. and Pseudostrandesia n. gen. Tanycypris siamensis n. sp. is described from Thailand. In addition, five species [Bradleystrandesia fuscata (Jurine, 1820), Bradleytriebella tuberculata (Hartmann, 1964), Nealecypris obtusa (Klie, 1933), Pseudostrandesia striatoreticulata (Klie, 1932), Spirocypris horrida (Sars, 1926)] are redescribed. A key to the genera is given. We propose three tribes: the nominal tribe Cypricercini McKenzie, 1971, as well as two new tribes, Bradleystrandesiini n. trib. and Nealecypridini n. trib. To evaluate the systematic relationships within this subfamily, phylogenetic analyses, based on morphological characters of valves and soft parts, were conducted. The Neighbour Joining (NJ) tree strongly supports the classification into three independent tribes, whereas the Maximum Parsimony (MP) tree shows that Bradleystrandesiini n. trib is actually a subgroup of the Cypricercini. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Handling editor: Luigi Naselli-Flores  相似文献   

5.
The cave-dwelling harpacticoid copepod fauna of Mexico is still yet to be known. There are only a few records related to karstic caves, but most refer to epigean forms. The analysis of samples collected in a cave system in Northern Mexico yielded two female specimens of an unknown harpacticoid copepod species which is described herein. It was assigned to the genus Stygonitocrella Petkovski, 1976 mainly because of the presence of a single endopodal segment on legs 1–4; the new species, S. mexicana n. sp. differs from its congeners by a combination of characters related to the segmentation and armature of the swimming legs 1–4, the fifth leg of the female, and the strcture of the antennae. Based on the current limits of Stygonitocrella, two new subgenera are proposed to recognize different morphological patterns based on the presence or absence of an inner baseoendopodal lobe in the female fifth leg, a character not evaluated before. This lobe is absent in the new species and in other five species now contained in the subgenus Eustygonitocrella. A lobe is present in the new subgenus Fiersiella, also with six species. This is the second record of Stygonitocrella in North America, after S. (Fiersiella) sequoyahi Reid, Hunt & Stanley, 2003; it is the only North American cave-dwelling species of the genus. It is suggested that the influence of marine transgressions in Northern Mexico was related to the origin of the new species as part of a group of troglobitic forms originated from marine interstitial ancestors that colonized the freshwater caves. A key for the identification of all the known species of Stygonitocrellais also provided.  相似文献   

6.
Numerous plant colonizations have been putatively attributed to deer, based on plant species traits, fur brushing or dung analyses. But, in woodlands, direct links between the expansion of zoochorous plant species and ungulate presence have seldom been reported. Based on coupled floristic and browsing surveys, repeated in time, we analysed the causes of the spatio-temporal progression of the epizoochorous species Cynoglossum germanicum over 30 years in a network covering an 11000 ha forested area in north-eastern France. In this area, deer populations reached a peak in the 1970s, then were reduced in order to meet forest management requirements. Although initially rare and protected locally, C. germanicum has displayed an unexpected fast colonization rate during the last few decades but only in the northern part of the forest, which previously had the highest animal populations. Absent in the initial 1976 survey, C. germanicum occurred in 8% of the plots in 1981, then 46% in 2006. Logistic regression models revealed that the probability of occurrence of C. germanicum in 2006 increased not only with light indicator values, in accordance with its ecological requirements, but also with past deer browsing pressure. This result provides direct evidence of long-lasting impacts of deer populations on plant species distribution. Combining two complementary traits, animal transport and herbivory avoidance, C. germanicum benefited from epizoochorous dispersal and, once established, was protected from deer browsing by the presence of toxic proteins in its tissues. Due to the triggering role of ungulates, this species switched from the status of rare to that of colonizer within only a few decades.  相似文献   

7.
K. Schulz 《Polar Biology》1996,16(8):595-600
A new genus and species,Mospicalanus schielae, collected at bathypelagic depth in the Antarctic Ocean, is described from female specimens and a stage V male. The new species is placed in the Spinecalanidae on account of the absence of fifth legs and leg 1 characteristics. It appears to be closely related toMimocalanus Farran. 1908, sharing apomorphic characters such as the lack of a rostrum, reductions of setal armament on the mouthparts, and absence of an outer spine on the first exopod segment of leg 1.Mospicalanus schielae can be distinguished from other spinocalanid genera by the setation of the antennary exopod, the maxillule, and the paecoxal endite of maxilla. Diagnostic characters of Spinocalanidae and Bathypontiidae are also discussed in order to clarify affiliation of genera tentatively assigned to the latter family. An updated key is given for the spinocalanid genera.  相似文献   

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9.
A new species of the Philichthyidae Vogt, 1877 (Copepoda: Poecilostomatoida), Procolobomatus hoi n. sp., is described based on adult female specimens recovered from the cephalic sensory canals of Etelis coruscans Valenciennes (Actinopterygii: Lutjanidae) caught off Ishigaki Island, the Ryukyu Islands, southern Japan. The new species differs from its congeners by having the following combination of characters: a long medial cephalic lobe about one-third the length of the body; an armature of five spines on the distal exopodal segment of leg 2; one long apical seta on the papillose leg 4; a caudal ramus armed with one medial and four terminal setae (two middle setae are inflated); and spinulose ornamentation covering the body. Procolobomatus hoi n. sp. is the first member of the genus reported from the western Pacific Ocean and from a host of the family Lutjanidae. Previous records of philichthyid copepods from Asian waters are also reported.  相似文献   

10.
The bathyal genus Penopus (Ophidiidae) is revised based on 23 specimens. One specimen from the Ryukyu Trench represents a new species, Penopus japonicus. The remaining 22 specimens were found on both sides of the Atlantic Ocean, and neither 28 meristic and morphometric characters nor several morphological characters show any differences between the two populations. This supports Séret (1988), who considered Penopus macdonaldi Goode and Bean 1896 a junior synonym of Penopus microphthalmus (Vaillant 1888). The new Japanese species can be separated from the Atlantic species by having fewer rays in the dorsal (117 vs. 135–158) and anal (89 vs. 106–122) fins, the squamation of the head restricted to the middle part of the preopercle versus the squamation covering the dorsum, preopercle and the opercle in part, a distinct spine behind the posterior nostril versus the spine hardly visible and 9 spines on the hind margin of the preopercle versus 4–7 spines.  相似文献   

11.
The first case of parasitic association between an eulimid mollusc (Gastropoda, Ptenoglossa) and a comatulid (Echinodermata: Crinoidea) is reported for Antarctica. The mollusc involved in the association is Eulima tumidula Thiele, 1912, which has now been ascribed to the genus Bathycrinicola Bouchet & Warén, 1986, never recognized before in Antarctica. This genus is present only in the NE Atlantic Ocean and the Mediterranean Sea, and encompass species which are specific parasites of the sessile stalked crinoids of the family Bathycrinidae. However, in Antarctica, Bathycrinicola tumidula (Thiele, 1912) exploits the endemic vagile comatulid Notocrinus virilis Mortensen, 1917, and attains the largest known dimensions (∼1 cm) for a Bathycrinicola species. The absence of suitable Bathycrinidae host in modern Antarctic benthic assemblages, as well as the long paleontological history of the genus Notocrinus in Antarctica, suggest a possible ‘host-switch’ phenomenon. This event could reasonably have occurred when many species underwent considerable bathymetric shifts, during the dramatic climatic changes that affected Antarctica.  相似文献   

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13.
Prospecting for potential natural enemies of the invasive lepidopteran tomato pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and the banana pest Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) on the Canary Islands archipelago, where no Trichogramma species were previously recorded, has led to the discovery of five distinct species. T. achaeae Nagaraja & Nagarkatti, T. bourarachae Pintureau & Babault, T. euproctidis (Girault) and T. evanescens Westwood are relatively widespread species. The fifth is close to T. brassicae Bezdenko, but differs sufficiently in the sequence of the ITS2 region of ribosomal RNA to warrant further investigation as a species probably new to science. Each species is treated in detail in order to facilitate identification in future using molecular and/or morphological characters, or a combination of both. All species are newly recorded for the Canary Islands, and the distribution of each within the islands and elsewhere is provided. Known host records are given within the Canary Islands and elsewhere. The most common species found, T. achaeae, is already being used in biological control programmes against T. absoluta in mainland Spain and field trials are ongoing to evaluate its effectiveness as a biological control agent of C. chalcites in banana crops.  相似文献   

14.
15.
Results of the revision of black swallowers (Chiasmodon) made by Melo (2009) are reconsidered. It is shown that separation of species by this author is based on individually varying characters investigated by this author on a limited number of fish, and some conclusions made in this study are based on factual mistakes. Validity of C. lavenbergi Prok. is restored, and C. asper Melo is included to its synonymy. It is shown that C. pluriradiatus Parr, as all other nominal species of the genus Chiasmodon, should be place in C. niger s. lato. Variation of C. niger-complex by dentition of gill arches and by some other meristic characters is pointed out. By armament of the gill apparatus, along with the typical form, forms α and β are discerned. The latter form is described in detail by two specimens from the eastern part of the Indian Ocean. It is found that form β corresponds to characters of the holotype of C. braueri while form α does not correspond to neither of the nominal taxa, attributed to C. niger s. l.  相似文献   

16.
The world of protists remains largely unexplored. A thorough electron-microscopic investigation of a few microlitres of deep-sea sediment from 2,964 m water depth near the South Sandwich Islands (Southern Ocean) revealed siliceous scales of filose-amoeba protist species, two of which have not been reported previously from Antarctica or from elsewhere in the Southern Hemisphere. However, all the species are known from other oceans and, in one case, from freshwater habitats. The Antarctic protistan scales belong to four species of filose amoebae: Pinaciophora fluviatilis Greef 1869, Pinaciophora denticulata Thomsen 1978, Pinaciophora multicosta Thomsen 1978 and Rabdiaster reticulata (Thomsen 1979) Mikrjukov 1999 nov. comb. Our study shows that (1) none of the species has been recorded from the Australasian biogeograpical region, (2) Pinaciophora multicosta and Rabdiaster reticulata are new records for the Southern Ocean and for the Southern Hemisphere as a whole, (3) prior to this investigation, Pinaciophora multicosta had been reported once only, from the Baltic Sea (Europe). These results highlight the problem of undersampling in the study of the global distribution of protists.  相似文献   

17.
Menu-Marque  S. A.  Zúñiga  L. R. 《Hydrobiologia》1994,292(1):81-87
A new species of Boeckella from limnetic samples of Laguna del Diamante, a high lake in the Andes (34°10 S) is described and illustrated. The species is defined by the characters of the male fifth leg: the right two segmented endopod bears four peculiar, short, claw-like spines, the left endopod is a simple finger-like projection. This species is related to B. gibbosa, also a species from the Andes and B. vallentini from Malvinas (Falkland Islands) and other subantarctic islands. It is distinguished from them by diagnostic features of the fifth legs of the male and abdominal structure and fifth legs of the female. Some current views on the features used in the taxonomy of the genus Boeckella are discussed.  相似文献   

18.
Thirty-two natural populations belonging to the eight species of the genus Lolium (ryegrass) or to Festuca pratensis (meadow fescue) were recorded for allelic frequencies at 13 isozyme loci. Cultivated ryegrass (L. perenne and L. multiflorum), meadow fescue, and the annual L. rigidum, are true outbreeders. The other species are true inbreeders, except for L. canariense, which shows a moderate level of cross fertilisation (20%). Hierarchical clustering from Nei's unbiased distance leads to four groups. The three self-pollinating, weed species, L. temulentum, L. remotum and L. persicum, belong to the first cluster, which is the most differentiated one. The second cluster comprises L. multiflorum, L. subulatum and most populations of L. rigidum. All L. perenne populations belong to the third cluster, as do two of L. rigidum. The average genetic distance within the L. perenne group is very low. Surprisingly, the fourth cluster groups together L. canariense and Festuca pratensis. The data suggest that L. rigidum is the species with the greatest diversity, and could be a common ancestor of the genus. Knowledge of historical processes of domestication could help to calibrate the molecular clock.  相似文献   

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