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1.
Two interesting chydorid Cladocera were found in caves of Hercegovina and are described here. The pantropical Alona diaphana King, 1853 was already known in this part of Europe, but was found in a cave environment for the first time. Alona hercegovinae n. sp. is an eyeless and stygobiontic species, and was found in three caves.  相似文献   

2.
Two new chydorids, Nicsmirnovius camerounensis (gen. nov., sp. nov.) and Bryospilus africanus n.sp. are described, based on material from Korup, Mundemba, Bakingili and Debunscha, all in the rainforests of southwest Cameroon. Morphological structures show that both taxa are only remotely related, and that, while Nicsmirnovius is clearly an alonine, Bryospilus might well be a chydorine chydorid. Small, taxonomically non-significant differences occurred among specimens of Bryospilus recorded in three different forest areas.  相似文献   

3.
Ulrik Røen 《Hydrobiologia》1987,145(1):125-130
Chydorus arcticus n.sp. (Cladocera: Chydoridae: Chydorinae) is described, figured, and differentiated from the closely relatedC. sphaericus (O.F. Müller, 1785). The known distribution of the species is given, and some aspects of speciation of arctic crustaceans are pointed out.  相似文献   

4.
Antarctylus humus n. gen., n. sp. from peat soil in the subantarctic is proposed. It can be distinguished from the most closely related genus Helicotylenchus by the arrangement of the esophageal glands, the broadly rounded lip region, and the tapering pointed tail in the female.  相似文献   

5.
Hudec  Igor  Illyová  Marta 《Hydrobiologia》1998,368(1-3):65-73
Pleuroxus denticulatus Birge, 1879 is a new invader from Western to Central Europe. Its occurrence in a Danube inundation (Slovak region) probably corresponds with the junction of the Danube and Rhine Rivers. The species was found among ‘the hard macrophytes’ of flowing arms and artificial ponds. A large variability was recorded in the number of valval denticles and in postabdominal denticulation. It is evident that part of the N. American populations is different from European populations. P. denticulatus seems to represent two sibling species. Both are characterised by an angular distal postabdominal corner, bearing 3–4 denticles, and by valval denticles on the postero-ventral corner. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
Subfossil remains of an unknown chydorid taxon were found in sediments of three lake basins in Finland. Two of the sites lie in southern Finland and one in NW Finnish Lapland. Similar remains are also known from four lakes in eastern Finland. The headshields are small, with a broadly rounded posterior margin and an attenuated rostrum. The headshields resemble those of Rhynchotalona falcataSars, but have a unique pore arrangement. There is one oval median pore near the posterior margin and two lateral pores which are displaced quite far in position. The shell is very small and has faint, longitudinal striae. Also, unknown postabdomens were found. These resemble postabdomen of R. falcatain shape but had 5–6 pairs of teeth instead of the 2 seen in R. falcata. The age of the remains varies between ca. 8500 14C yr BP and recent decades. The species appears to have been present in the entire country during most of the Holocene. On the basis of the pore arrangement, the new species cannot be put into any previously known genus. A tentative name Unapertura latensn. sp. is suggested until intact specimens are found and described.  相似文献   

7.
Dumontia oregonensis, a cladoceran representing a new family in the Order Anomopoda is described from rain pools in the Agate Desert, Oregon, U.S.A. The proposed family, Dumontiidae, is the newest family within Anomopoda that is not just a reshuffling of already-known species. The general appearance of this novel cladoceran is similar to that of members of the family Macrothricidae. However, a detailed examination of the trunk limbs, particularly of the second pair of limbs, showed that the new species lacks the scraper-setae typically observed in all members of the recently erected suborder Radopoda, to which macrothricids belong. Instead, limb morphology suggests a closer relation of Dumontiidae to the family Daphniidae. Dumontiidae appears to be a `missing' link between the suborder Radopoda and the `non-radopodid' anomopods. The families Daphniidae, Ilyocryptidae, Bosminidae, Moinidae and the new Dumontiidae are similar in that they lack of typical radopodid setae on the second pair of trunk limbs. Further studies on the limb morphology of non-radopodid cladocerans are required to solve the phylogenetic relationships among the members of the order Anomopoda.  相似文献   

8.
Sauertylenchus labiodiscus n. gem, n. sp. is described and illustrated from soil around Rhagodia sp. in Australia. It can be distinguished from the most closely related genus Tylenchorhynchus Cobb, 1913 by the distinctly set-off, rounded, lip region with a conspicuous labial disc, and long thin stylet. The face view and spicules of Sauertylenchus labiodiscus are illustrated with scanning electron micrographs. The subfamilies Tylenchorhynchinae and Merlininae ale discussed.  相似文献   

9.
Numerous specimens of Pseudomoraria triglavensis gen.n., sp.n. were collected from small, high-alpine, reservoir Moilec. The reservoir is situated in the centre of Triglav national park (NW Slovenia) at an altitude of 1690 m. The new genus differs from related genera Moraria, Morariopsis and Paramorariopsis by the reduced articulation of exopodites and endopodites in both sexes. It also differs from Moraria by possessing sexually dimorphic furcal rami. Detail taxonomic differences between these related genera and their ecology are discussed.  相似文献   

10.
Juan C. Paggi 《Hydrobiologia》1992,231(3):141-151
I. elegans n.sp. from the Parana River, northeastern Argentina is proposed and its morphological features are compared with those of the apparently related I. agilis. Its outstanding characteristics are the long 2rd to 5th setae of ventral margin of the valves, the rudimentary nature of defensive setae, the low number of spines in the preanal lobe of postabdomen and the unequality of the length of the setae in the outer distal lobe of first trunk limbs.Finding of this new species suggests that I. agilis would be a complex of species and its records should be revised.  相似文献   

11.
Kotov  Alexey A. 《Hydrobiologia》2000,437(1-3):17-56
The five endemic species of Kozhowia Vasiljeva & Smirnov, 1969 (Branchiopoda: Anomopoda: Chydoridae) are redescribed based on material from Lake Baikal, including types of all species. Two well-defined groups were found. A new genus Parakozhowia n.gen., with one species, P. baicalensis Vasiljeva & Smirnov, 1969 n. comb., is erected. An extended diagnosis for the genus Kozhowia is presented. Parakozhowia n. gen. differs from Kozhowia in (1) antennal formula; (2) proportions of postabdomen; (3) number of setae on exopodite IV; (4) presence of soft setae of endopodite IV; (5) presence of a limb VI, and (6) presence of an inflated rostrum in the adult male of Kozhowia. An improved key for the discrimination of the species is given. Thoracic limbs of all species were given special attention. There are six setae on exopodite IV in Parakozhowia n.gen., as normal for Aloninae, while only four setae and a rudimentary hillock were detected on exopodite IV in the species of Kozhowia. Kozhowia is a true member of the Aloninae, and the closest relative of Parakozhowia and Camptocercus, meaning that the diagnosis of the Aloninae must be amended: the number of setae on exopodite IV in Aloninae may vary from 4 to 6.  相似文献   

12.
The chydorid species Chydorus reticulatus Daday, 1898 and Chydorus ventricosus Daday, 1898 are redescribed and literature records reevaluated on the basis of new material from India.Contribution 9 Department of Biology, Indiana University, Bloomington. This study was supported in part by NSF Grant DEB76-20237 to D. G. Frey.  相似文献   

13.
Igor Hudec 《Hydrobiologia》2000,421(1):165-178
The genus Kurzia is divided into two subgenera: Kurzia s. str. and Rostrokurzia n. subg. Subgenus Kurzia includes Kurzia (K.) latissima Kurz, 1874, with a palearctic -, Kurzia (K.) polyspina n. sp. with a neotropic - , and Kurzia (K.) cf. media (Birge, 1879) with a nearctic distribution. Rostrokurzia includes Kurzia (R.) longirostris Daday, 1898 (pantropical distribution), and Kurzia (R.) brevilabris Rajapaksa & Fernando, 1986, from subtropical and tropical Asia. Kurzia latissima Kurz, 1874, from Central Europe is redescribed in detail.  相似文献   

14.
Previously only a single species of Ilyocryptus Sars , 1862 (Cladocera: Anomopoda: Ilyocryptidae) was reported from Thailand, I. spinifer Herrick , 1882. However, our examination of numerous samples from this country resulted in the discovery of four other species of Ilyocryptus. Ilyocryptus thailandensis sp. nov. is described from two adjacent water bodies in Uttaradit Province, North Thailand. It has at least two characters which distinguish it from any other species of the Ilyocryptus: (1) a row of lateral setae reaching medial anus, and continuing along preanal margin up to base of the postabdomen; (2) a large projection bearing the sensory setae, situated on the coxal region of antenna II. It appears to be a rare species, may be, endemic of the North Thailand.  相似文献   

15.
Rhizonema sequoiae n.gen, u. sp. is described from the roots of Coast Redwood, Sequoia sempervirens (D. Don) Endl., growing near Lake Lagunitas, Marin County, California. Rhizonema females are annulated over their entire bodies, are wholly embedded in host tissue, and secrete an abundant amount of gel material. Mature females do not form a cyst. The vulva is located on a large posterior terminal cone, and the anus is on the dorsal vulval lip. Esophageal glands of the second-stage larvae fill more than half of the body cavity. Tails of the vermiform males are blunt, and a cloacal tubus is present.  相似文献   

16.
17.
A new genus Sumatrella gen. n. is described and illustrated based on the new species Sumatrella chelonica sp. n. collected in Sumatra, Indonesia. The new genus belongs to the family Oplitidae based on its hypertrichous internal malae and the absence of strongly sclerotized structures on the dorsal shield. The new genus is closely related to the genus Chelonuropoda Sellnick, 1954 but the transverse furrow on ventral idiosoma close to coxae IV and the strongly sclerotized C-shaped dorsal line are missing in the new genus. These characters can be found in species of Chelonuropoda.  相似文献   

18.
The species group of Alona karua is raised to generic rank and named Karualona. The genus is defined on the basis of a number of characters of the body and its appendages. Tentative new microcharacters are introduced, related to the type and length of selected setae of P1, P2, P3 and P4. Two new species are described, one from the island of Socotra and one from Mexico. A key to the five currently recognized species is given.  相似文献   

19.
Thecavermiculatus gracililancea n. gen., n . sp. is described from the roots of Festuca myuros L. ("rattail fescue") a range grass in Monterey County, California. Thecavermiculatus females have a slight terminal prominence on which are located the vulva and anus, while its closest relatives, Atalodera and Sherodera, have a large terminal prominence. Furthermore, in T. gracililancea the hatched second-stage juveniles are retained in the female body while Atalodera and Sherodera females retain embryonated eggs.  相似文献   

20.
Two new species of heterolobosean amoebae from anoxic environments, Monopylocystis visvesvarai and Sawyeria marylandensis, are described on the basis of light microscopy, electron microscopy, and their phylogenetic affiliation based on analyses of nuclear small-subunit ribosomal RNA gene sequences. Both species lack mitochondria but have organelles provisionally interpreted as hydrogenosomes, and neither can tolerate aerobic conditions. As their conditions of culture do not exclude all oxygen, they may be microaerophiles rather than strict anaerobes. Both species have unusual nucleolar morphologies. Monopylocystis visvesvarai, from a marine sediment, has nucleolar material distributed around the nuclear periphery. It is the first non-aerobic heterolobosean protist for which a cyst is known; the cyst is unmineralized and unornamented except for a single, raised, plugged pore. Sawyeria marylandensis, from an iron-rich freshwater stream, has nucleolar material distributed in one or two parietal masses, which persist during mitosis. In phylogenetic analyses of small-subunit rRNA gene sequences, Monopylocystis visvesvarai, Sawyeria marylandensis and Psalteriomonas lanterna converge to form a single clade of non-aerobic (anaerobic/microaerophilic) heteroloboseans.  相似文献   

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