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1.
The status of the Mesocyclops from lake Biwa is reexamined and a new species, Mesocyclops dissimilis n. sp., distinct from M. thermocyclopoides Harada, 1931, is described.  相似文献   

2.
A revision is made of the African Mesocyclops species, based on type material (when extant) and on collections from various parts in Africa.Diagnostic characteristics are: presence or absence of spinule patterns on antennular segments, structure of the hyaline membrane of the 17th antennular segment, spine pattern on the basipodite of the antenna, armature of the maxillulary palp, presence or absence of a spine on the basipodite of P1, armature of the connecting lamella, coxopodite and basipodite of P4, armature of the apical spines of Enp3P4, armature of the last thoracic segment, genital segment and the other abdominal segments, armature of the furcal rami and structure of the receptaculum seminis.First, the taxonomical status of M. leuckarti (Claus) is redefined; this species does not occur in Africa and its geographical range is restricted to Europe and the western part of Northern Asia. On the African continent, twelve other taxa are found. Four are described as new to science: M. kieferi sp.n., M. dussarti sp.n., M. spinosus sp.n. and M. aequatorialis similis subsp.n. The remainder are: M. major Sars, M. tenuisaccus (Sars), M. paludosus Lindberg, M. salinus Onabamiro, M. ogunnus Onabamiro, M. aspericornis (Daday), M. rarus Kiefer and M. aequatorialis aequatorialis (Kiefer).Their geographical distribution is discussed. Eleven taxa are restricted to the African continent (including the Arabian Peninsula and the Canary Islands). One taxon is also found in the Oriental Region. Madagascan representatives are briefly mentioned.The importance of breeding and cross-breeding experiments should be stressed in copepod taxonomy. Experiments were performed on African species and M. leuckarti to evaluate the morphological characters used in the present study, and intraspecific morphological variability was examined up to and including the third generation (Van de Velde, in press).In future one should critically reconsider the so-called cosmopolitan species; they may indeed represent a complex of related taxa, each with a geographical range more restricted than that of the species-complex itself.Abstracted from the author's Ph.D. thesis, State University of Ghent, 1982.Abstracted from the author's Ph.D. thesis, State University of Ghent, 1982.  相似文献   

3.
Four species of the genusMesocyclops (Cyclopoida: Cyclopidae) are reported from Israel:Mesocyclops kieferi Van de Velde, 1984,Mesocyclops aequatorialis similis Van de Velde, 1984,Mesocyclops ogunnus Onabamiro, 1957 andMesocyclops arcanus n.sp. The new species, close toM. kieferi, is described and some remarks are given for the other species.  相似文献   

4.
Hołyńska  Maria  Sinh Nam  Vu 《Hydrobiologia》2000,429(1-3):197-206
Mesocyclops ferjemurami sp. nov. is described from Central Vietnam, North India and Sri Lanka. It differs from all congeners in having a unique spinule ornamentation on the caudal surface of the antennary basipodite: the `leuckarti-type' spinule pattern is supplemented with a group of spinules at the height of implantation of the medial setae, and proximal to this group a triangular spinule field occurs, the longest side of which runs more or less parallel to the oblique row of tiny spinules starting at distal half of the medial rim. It is suggested that Mesocyclops ferjemurami is closely related to Mesocyclops pehpeiensis Hu, 1943 and Mesocyclops papuensis Van de Velde, 1987.  相似文献   

5.
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   

6.
The rotifer fauna has been investigated at three littoral brackish water localities in the Öresund, Denmark. Samples taken from plankton, periphyton and psammon yielded 14 rotifer species. Two of these are new to science and are described herein. Both species were found in psammon at the same locality. Erignatha longidentata n. sp. is characterised by having toes with swollen bases, convex outer margins and concave inner margins. The trophi have a pair of large subunci and relatively large unci. The other new species, Paradicranophorus wesenberglundi n. sp., is characterised by having two large red pigmented eyespots and large conical toes. The rami are lyrate, and intramallei and supramanubria are present in the mallei.  相似文献   

7.
8.
Eodiaptomus phuphanensis n. sp. is described from two localities in the Phu Phan National Park, northeast Thailand. The new species is the eighth member of the genus Eodiaptomus and the third species recorded from Thailand. It belongs to the lumholtzi‐group, and is most closely related to E. sanoamuangae Reddy and Dumont , 1998. The third endopodite‐segment of P2‐P4 in both sexes of E. phuphanensis n. sp. bears seven setae as in E. sanoamuangae, instead of six as in the remaining species of the genus. Nevertheless, the new species can be distinguished from the other congeners by the distinct shape of the endopodite of the male right P5 and the absence of hairs on lateral margins of the female caudal rami.  相似文献   

9.
A new species of rotifer, Rhinoglena kutikovae n.sp. (Monogononta: Epiphanidae), is described from a freshwater lake in the Bunger Hills, East Antarctica. The new taxon is characterized by the following combination of characters: body conical to vase-shaped; a single toe; distal foot pseudosegment bulged; tail prominent, semi-circular; two small spherical pedal glands with common duct, forming a complex with caudal ganglion; trophi with seven major teeth with offset head and two smaller teeth without offset head. The new species is compared with R. fertoeensis, R. frontalis and R. tokioensis, of which scanning electron microscopic information is presented of the trophi. R. kutikovae n.sp. is probably a relict species that survived Quaternary glaciations in glacial lacustrine refugia on the Antarctic continent.  相似文献   

10.
Hae-Lip Suh 《Hydrobiologia》1993,259(3):187-193
Anthessius kimjensis n. sp. is described based on the specimens recovered from the pelecypod Solen grandis Dunker in the Korean coast of the Yellow Sea. The new species is distinguished from congeners by having a combination of characters: setal formula II, I, 5 on distal segment of leg 4 exopod, three terminal hooks on distal segment of second antenna, and ratio of length to width on caudal ramus (2.2:1).  相似文献   

11.
In the shallow and eutrophic subtropical aquatic ecosystems, which it generally inhabits, the omnivorous copepod Mesocyclops thermocyclopoides encounters a wide variety of animal prey types including ciliates, rotifers, and cladocerans. We studied prey selectivity in laboratory-reared adult females of this species given a choice of (i) prey types belonging to different taxa (ciliates, rotifers, cladocerans, and cyclopoid nauplii), and (ii) different prey species within a taxonomic group differing in body size, morphology or behaviour. We also tested the effect of different proportions of prey species on its selectivity. Prey type proportion had no significant effect on selectivity of the copepod, nor was there any evidence of switching based on the relative abundance of prey. Among the ciliate prey species tested, the largest species, Stylonychia mytilus was positively selected regardless of its relative abundance, while the smallest, S. notophora was selected only when its density was higher. Offered a choice of three species of a brachionid rotifer differing in size, the copepod selected the largest of them, Brachionus calyciflorus, and avoided the smallest B. angularis. The evasive rotifer Hexarthra mira was also avoided. When prey choice included three cladoceran species Daphnia similoides, Moina macrocopa and Ceriodaphnia cornuta, the copepod selected the intermediate-sized M. macrocopa regardless of the abundance of the other two species. Although it fed on Mesocyclops nauplii when there was no choice, M. thermocyclopoides avoided them when alternative food was available. In a multispecies prey choice test, the copepod selected predominantly the rotifer B. calyciflorus and the cladoceran M. macrocopa. We suggest that the prey selectivity patterns shown by M. thermocyclopoides are adaptive in that they lead to ingestion of the most profitable prey.  相似文献   

12.
13.
Helmut Kunz 《Hydrobiologia》1995,297(2):83-98
Two new species of marine, sand-dwelling harpacticoids are described: Phyllopodopsyllus pallaresae n. sp. from Namibia, and P. hartmannorum n. sp. from Tanzania. The hitherto unknown male of P. xenus (Kunz) is described from Namibia. Further remarks are made on P. furciger Sars from Tanzania.Zwei neue sandbewohnende Harpacticoiden-Arten werden beschrieben: Phyllopodosyllus pallaresae n. sp. von Namibia und Phyllopodopsyllus hartmannorum n. sp. von Tansania. Außerdem wird das bisher unbekannte Männchen von Phyllopodopsyllus xenus (Kunz) von Namibia beschrieben. Morphologische Merkmale von Phyllopodopsyllus furciger Sars werden anhand eines Fundes von Tansania ergänzt.  相似文献   

14.
During the “Workshop on Arctic tardigrades” at the Danish Arctic Station (Qeqertarsuaq, Disko Island, Greenland) an undescribed species of Dactylobiotus was found in freshwater sediments of the Isunngua spring. We have the honour and pleasure to describe this new taxon that we dedicate to all participants of that symposium, naming the species Dactylobiotus octavi sp. n. The animals appear similar to Dactylobiotus dispar and Dactylobiotus haplonyx with the presence of a very short secondary branch in the claws of the first three pairs of legs, but they differ from these species in the size of claw and buccal tube width. This new species also has peculiar ornamented eggs. The eggshell consists of bowl-like processes, each one surrounded by a band of fine pores. A morphological parsimony analysis to identify phylogenetic relationships among D. octavi sp. n. and the other Dactylobiotus species was performed, obtaining inconclusive results. The discovery of this new species increases an unsolved paradox in tardigrade systematics related to the presence of closely related species which share a very similar morphology of the animals but clearly differ in their egg morphology, while, conversely, there are species belonging to different evolutionary lines that have similar eggs, but very different adult morphology. The finding of D. octavi sp. n. increases the already high number of species found in Disko Island and once again underlines the importance of tardigrades in the biodiversity of the Arctic area.  相似文献   

15.
To more confidently assess phylogenetic relationships among astome ciliates, we obtained small subunit (SSU) rRNA sequences from nine species distributed in six genera and three families: Almophrya bivacuolata, Eudrilophrya complanata, Metaracoelophrya sp. 1, Metaracoelophrya sp. 2, Metaracoelophrya intermedia, Metaradiophrya sp., Njinella prolifera, Paraclausilocola constricta n. gen., n. sp., and Paraclausilocola elongata n. sp. The two new species in the proposed new clausilocolid genus Paraclausilocola n. gen. are astomes with no attachment apparatus, two files of contractile vacuoles, and an arc-like anterior suture that has differentiations of thigmotactic ciliature on the anterior ends of the left kineties of the upper surface. Phylogenetic analyses were undertaken using neighbor-joining, Bayesian inference, maximum likelihood, and maximum parsimony. The nine species of astomes formed a strongly supported clade, showing the subclass Astomatia to be monophyletic and a weakly supported sister clade to the scuticociliates. There were two strongly supported clades within the astomes. However, genera assigned to the same family were found in different clades, and genera assigned to the same order were found in both clades. Thus, astome taxa appear to be paraphyletic when morphology is used to assign species to genera.  相似文献   

16.
Evolutionary relationships were investigated in the genus Mesocyclops, a pantropical freshwater cyclopid group. In the phylogenetic analyses that involved all 71 known species, and used 81 morphological characters (265 character states) mainly of the adult females, two different approaches were applied: global parsimony, and a new distance method based upon the recognition of sister‐groups on the basis of minimal distances iteratively corrected for unique character states (MICSEQ). In coding of the characters, half of which showed intraspecific variation, the ‘scaled’ method was employed, which assumes that any trait between its absence and fixed presence passes through a polymorphic stage. Impact of the reference points on topology of the trees generated by the parsimony method was tested in three ways where the outgroups comprised: (1) nine species representing six genera of two subfamilies; (2) three species from two genera supposedly not distant from Mesocyclops; and (3) one presumably close and one distant relative of Mesocyclops. The trees generated by the parsimony‐based and corrected distance methods agreed as to the monophyly of the following groups: reidae‐clade (M. reidae, M. chaci, M. yutsil); rarus‐clade (Mesocyclops annae, M. pseudoannae, M. splendidus, M. rarus, M. paludosus, M. darwini, M. dayakorum); annulatus‐clade (Mesocyclops intermedius, M. ellipticus, M. paranaensis, M. annulatus, M. tenuisaccus); meridianus‐clade (Mesocyclops meridionalis, M. varius, M. venezolanus, M. brasilianus, M. pseudomeridianus, M. meridianus); major‐clade (Mesocyclops major, M. pilosus, M. insulensis); dussarti‐clade (M. dussarti, M. dadayi, M. isabellae, M. thermocyclopoides); pubiventris‐clade (M. pubiventris, M. medialis, M. brooksi, M. notius). A majority of the analyses support a clade of the ‘true’Mesocyclops including all ingroup species except the reidae‐group, and point to monophyly of the Old World species lacking medial spine on P1 basipodite. There were, however, some components for which the two procedures, regardless of the outgroup choice and/or character set, suggested different relationships. Basal relationships of Mesocyclops[between M. edax (North and Central America), the Neotropical species (M. longisetus, M. araucanus, M. evadomingoi, meridianus‐ and annulatus‐clade), Old World group (P1 basipodite without medial spine) and the rarus‐clade (Old World; P1 basipodite with medial spine)] remained unresolved. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society, 2006, 147 , 1–70.  相似文献   

17.
A new genus and new species of the family Cletopsyllidae Huys & Willems, 1989 from deep-sea sediment in the Gulf of Mexico, are reported and fully described and illustrated. The new genus Pentacletopsyllus (type species: P. montagni sp. n.) can be distinguished from the four known genera of the family by antennule segmentation, length ratio of first and second endopodal segments of P1, and armature pattern on P5 exopod. It also differs from its sister genera by the rostrum being bifid at the tip, third segment of the female antennule having a smooth posterior margin, the baseoendopod of P5 with biarticulate outer setophore bearing basal seta, and female caudal rami without lobate expansion. A revised key to species of the family Cletopsyllidae Huys & Willems, 1989 is provided.  相似文献   

18.
Seven new species of Eimeria are described and figured from the freshwater fishes of Ontario and Quebec, Canada. They are Eimeria catostomi sp. n. and E. fernandoae sp. n. from Catostomus commersoni (Lacépède), E. etheostomae sp. n. from Etheostoma exile (Girard), E. hoffmani sp. n. from Umbra limi (Kirtland), E. micropteri sp. n. from Micropterus dolomieui Lacépède E. pungitii sp. n. from Pungitius pungitius (Linnaeus), and E. salvelini sp. n. from Salvelinus fontinalis (Mitchill). Furthermore, 2 new host records and 2 new distribution records for North America are reported for E. anguillae Léger & Hollande, 1922 and E. truttae Léger & Hesse, 1919 respectively. Finally, morphologically similar oocysts found in various cyprinids are regarded as belonging to E. iroquoina Molnar & Fernando, 1974.  相似文献   

19.
Two new species ofHalicyclops are described from plankton samples taken in two localities in the Amazon River mouth area, State of Pará, Brazil.Halicyclops lindbergi sp.n. resemblesH. hurlberti andH. clarkei from which it differs by a combination of characters in leg 5, the anal pseudoperculum and the caudal rami. The other new species,H. dussarti, is most morphologically similar toH. pilosus, but they are separated by differences in legs 1 and 5 as well as in the ornamentation of the middle caudal setae.  相似文献   

20.
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