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1.
2.
Species of the marine nematode genus Pontonema have been found to dominate the macrobenthos under abnormally high conditions of particulate organic enrichment. Populations from organically enriched habitats in six localities (Kiel fjord, Germany; the Garroch Head sewage-sludge dump ground in the Firth of Clyde, Scotland; Cornelian Bay, N.E. England; the Tyne estuary, N.E. England; Sete, N.W. Mediterranean, France; Blanes Bay, N.W. Mediterranean, Spain) have been compared. Multivariate analyses of 16 morphometric characters in males, and 13 in females, shows that each population is significantly different morphologically from every other population. However, there is morphological overlap between the populations, and it is considered pragmatic to recognize three species in this group, based on a few stable morphological characters: P. vulgare (Bastian, 1865) from the Baltic, P. alaeospicula Bett and Moore 1988 from the UK sites, and P. mediterranea sp. nov. from the Mediterranean. P. mediterranea sp. nov. is described. The species were not found to have established sympatry in this study, unlike many other opportunistic taxa from organically enriched habitats, and the significance of this is discussed.  相似文献   

3.
《Journal of Natural History》2012,46(37-38):2329-2356
A lineal “island” theory is proposed to account for the dispersal of marine/estuarine, supralittoral talitrid populations, both to and from isolated shore “islands” on continental and true oceanic islands. Evolution may occur following dispersal to shores that are contiguous with ecologically open habitats, inclusive of sub-tropical forest litter and caves. Specific hypotheses of the lineal “island” theory are therefore: the conventional wrack hypothesis 1 – direct from marine supralittoral wrack to subtropical forest litter; the driftwood hypothesis 2(a) – direct from marine supralittoral driftwood to subtropical forest litter; the driftwood hypothesis 2(b) – direct from the marine supralittoral driftwood to caves opening on a marine supralittoral; and the driftwood hypothesis 2(c) – direct from the marine supralittoral driftwood via caves to subtropical forest litter. Circumstantial evidence supporting each hypothesis is presented using the ecology and distribution data of the talitrid fauna of the northeast Atlantic islands, north of 25°N and south of 40°N, including the Canaries, Madeira and the Azores archipelagos. The currently known talitrid fauna of all these islands includes 15 species: seven endemic, subtropical landhoppers, two synanthropically introduced landhoppers, three wrack generalists, one sand-burrowing specialist, one specialist cavehopper, and one specialist driftwood hopper. Based on distributional data from the northeastern Atantic islands, specialist driftwood hoppers have a long distance dispersal capability, which makes them potential colonizers of distant oceanic islands. Talitrids provide an excellent model of dispersal and speciation, whose evolutionary pathways can be solved by modern genetic methods.  相似文献   

4.
《Journal of Natural History》2012,46(23):2125-2136
A morphological investigation of Leydigia parva Daday, (Chydoridae: Anomopoda: Cladocera), based on specimens from Paraguay (type specimens) and Brazil, clarifies its position in the subfamily and prompts its assignment to a new genus, Parvalona. The affinity of this rare benthic chydorid with Leydigia Kurz, 1875 and Alona Baird, 1843, in which this taxon was placed earlier, is discussed.  相似文献   

5.
《Journal of Natural History》2012,46(16):2119-2131
Recent surveys of the plethodontid salamander fauna of Oaxaca, Mexico, disclosed the existence of a new, morphologically distinct arboreal species of the genus Pseudoeurycea. The new species, described here, is from the Sierra Mazateca in northern Oaxaca. Sequences of 1833 base pairs of the 16S, cytochrome b and ND4 mitochondrial DNA (mtDNA) genes from the new taxon were used to assess its phylogenetic position. Previous phylogenetic analyses based on mtDNA supported recognition of four clades within Pseudoeurycea: P. bellii, P. gadovii, P. juarezi and P. leprosa-Lineatriton species groups. One additional species, P. unguidentis, was not closely allied to any of the four groups. Re-analysis including the additional sequences reported here establishes a sister-group relationship between the new species and P. unguidentis. Moreover, it supports this clade as part of the P. juarezi species group.  相似文献   

6.
The egg, three larval instars, and puparium of Pherbina mediterranea are described. The duration of the various immature stages indicates that this specis is univoltine and spends the winter as quiescent larvae. The biology, phenology and geographical distribution are presented. The main features of the larvae are illustrated with scanning electron micrographs. A key to the adults of genus Pherbina is given.  相似文献   

7.
ABSTRACT

Species of the genus Platorchestia occur both in the northern hemisphere (18 species) and southern hemisphere (three species plus a synanthropically introduced species in South America and South Africa). The greater number of endemic Platorchestia species in the North Pacific Ocean suggests that it could be the epicentre of evolution for this genus. North-western Pacific Platorchestia includes 15 species which occupy five ecotopes: wrack (seven species), terrestrial leaf litter (five species), freshwater (one species), marsh (one species) and tentatively present in caves (one species). North-eastern Pacific Platorchestia includes only one putative driftwood specialist, with no other species found in North American coastal habitats. This compares with three good endemic Platorchestia species (plus two putative additional species) and only two ecotopes: wrack (three species) and freshwater (two species) from the North Atlantic Ocean, inclusive of the Gulf of Mexico and Mediterranean Sea. Insufficient data is available to consider Platorchestia zoogeography for the Arabian Sea and Bay of Bengal. Synanthropic dispersal involving Platorchestia in Polynesian outrigger canoes, or in solid ballast carried in the holds of wooden sailing ships has been identified as a potential complicating factor in the zoogeography of this genus. Platorchestia is proposed to have arisen on Laurasia and is therefore basically a northern hemisphere genus. Questions concerning Platorchestia zoogeography and evolutionary ecology are posed and two methods (more intensive field sampling and molecular genetics) are suggested to be the way to solve them.  相似文献   

8.
《Journal of Natural History》2012,46(10):1487-1512
The genus Platythelphusa is revised and six species are recognized. These species are P. armata A. Milne-Edwards, 1887, P. maculata (Cunnington, 1899), P. conculata Cunnington, 1907, P. tuberculata Capart, 1952, P. polita Capart, 1952 and P. echinata Capart, 1952. A seventh taxon, P. denticulata Capart, 1952 is considered here to be a junior synonym of P. conculata. A diagnosis for each species is provided and most are figured from the type. Keys to the families of African freshwater crabs and to the genus Platythelphusa are also provided.  相似文献   

9.
《Journal of Natural History》2012,46(20):2655-2668
Examination of fossil and Recent specimens from the Sicilian area belonging to the Phylactella labrosa ‘complex’ revealed two new species: P. mediterranea sp. nov., a Pleistocene-to-Recent taxon and P. megarensis sp. nov., from Pleistocene sediments from eastern Sicily. Ecological, geographical and stratigraphical distribution of both new species are discussed also in comparison with P. labrosa.  相似文献   

10.
Belgrandiella A. J. Wagner, 1927 is a genus comprising minute snails with conic or turriform shells that are facultative stygobionts, inhabiting subterranean waters and springs. Few specimens or even empty shells of this taxon can be found, so the taxonomy is based mostly on the shell morphology and geographic distribution. Anatomy is known for a few taxa, and its usefulness is restricted. This, coupled with a popular idea that isolation is the first factor shaping divergence and speciation of the spring/cave fauna, resulted in dozens of nominal species of Belgrandiella, known from shells at a given locality. Herein we present shells, anatomy and four molecular markers (nuclear H3, 18S and 28S and mitochondrial cytochrome oxidase subunit I) in Belgrandiella from 16 localities in Slovenia, northern Croatia, and Bosnia and Herzegovina. Five sites are type localities of Boleana umbilicata, Belgrandiella kusceri, Belgrandiella krupensis, Belgrandiella zermanica and Belgrandiella robusta, respectively. Considering the shell and geographic distribution, we have determined B. cf. robusta Belgrandiella cf. croatica, Belgrandiella cf. fontinalis, Belgrandiella cf. kuesteri, Belgrandiella cf. pageti and Belgrandiella cf. koprivnensis The shells of all, as well as penes and female reproductive organs of two putative, species have been illustrated. Molecular analysis indicates four distinct clades, most probably of species rank for B. kusceri, B. cf. kuesteri, B. cf. fontinalis and B. cf. koprivnensis. Four nominal species (B. krupensis, B. robusta, B. umbilicata and B. zermanica) and one genus (Boleana) must be synonymised with Belgrandiella kusceri, and there are no more than four valid, biological species in the studied Belgrandiella. The molecular divergence is completely unmirrored by high morphological variability. Hence the level of endemism is markedly overestimated in these snails.  相似文献   

11.
Five new species of bariliin cyprinid fishes are described from West Africa. Three belong to the genus Leptocypris and two to Raiamas. One species of each genus is from Guinea (Konkoure river) and from Sierra Leone (Taia and Little Scarcies rivers), the other, a Leptocypris, is from Cameroon (Cross River). A taxon of indeterminate generic identity from Guinea is also described. The phylogenetic relationships of the bariliins are hypothesized and in this light their geographical distribution is compared with that of other cladistically analysed African freshwater fish groups. The significance to West African fish distribution of the Togo-Benin (Dahomey) Gap is discussed.  相似文献   

12.
13.
《Journal of Natural History》2012,46(41-42):2671-2689
The ground beetle taxon Kashmirobroscus gen. nov. and two species Kashmirobroscus mirabilis sp. nov. and Kashmirobroscus ortrudae sp. nov. are described from the Northwest Himalaya of Pakistan. Diagnostic characters of both new species are figured and their distributional areas are mapped. Several features of the new genus are discussed to work out its systematic position within Broscini. As a result, Kashmirobroscus is proposed as a sister taxon of the East Asian genus Eobroscus Kryzhanovskij, 1951, of the subtribe Broscina. In addition, new data relating to systematics and distribution of all the known species of the genus Eobroscus are provided. The taxon Orobroscus Morita, 1990 is proposed as a junior synonym of Eobroscus Kryzhanovskij, 1951, and Eobroscus uenoi Morita, 1995 is proposed as a junior synonym of Eobroscus bhutanensis Morvan, 1982, a macropterous species with a wide distribution in the eastern parts of High Asia. http://www.zoobank.org/urn:lsid:zoobank.org:pub:1775013D-FE87-41CA-87AF-D730E809331B  相似文献   

14.
《Journal of Natural History》2012,46(12):2293-2314
A new genus and species of Rotoitidae, Chiloe micropteron Gibson and Huber, is described from females and one male from Chile. The taxon is the second known genus and species, and the male is the only one known for the family. Scanning electron micrographs illustrate external and internal structure of C. micropteron females, and external structure of Rotoita basalis  相似文献   

15.
During the last three decades, strong progress was made in the taxonomy of the family Chydoridae (Crustacea: Cladocera), and the results of these revisions have become a valuable confirmation of the non-cosmopolitanism in the cladoceran distribution. But, to date, delineation between several chydorid genera (Pleuroxus Baird, 1843, Picripleuroxus Frey, 1993, Alonella Sars, 1862 and Disparalona Fryer, 1968) has been intuitive rather than based on careful diagnostics. Disparalona is a cladoceran genus with a complicated and confused taxonomy. We compiled a checklist of all formal taxa belonging to this genus in current understanding. Our study comprises a taxonomic revision of the North American, African and East Asian populations of D. cf. hamata with the aim of clarifying their species and generic status. We redescribe D. hamata (Birge, 1879) based on material from North America and D. chappuisi (Brehm, 1934) based on material from Africa. The latter is common in tropical–subtropical Asia, with a distribution range reaching the Far East of Russia. The second taxon from Africa is provisionally identified as D. cf. striatoides (?rámek-Hu?ek, 1946), which was described initially from the Czech Republic. Further comparison is needed for a final conclusion on conspecifity of European and African populations provisionally placed to this taxon. At the current level of knowledge Mixopleuroxus Hudec, 2010 must be accepted as a subgenus of the genus Disparalona. The diagnoses of Disparalona s. str. and D. (Mixopleuroxus) are provided. Disparalona s. str. includes D. ikarus Kotov and Sinev, 2011, D. leei (Chien Shing-ming, 1970), D. rostrata (Koch, 1841) and D. smirnovi Sinev, 2015, while D. (Mixopleuroxus) includes D. hamata, D. chappuisi and D. striatoides. D. leptorhyncha (Daday, 1905) and D. caudata Smirnov, 1996 are not described adequately, but they also probably belong to the latter subgenus. The status of D. acutirostris (Birge, 1879) must be clarified in the future.

www.zoobank.org/urn:lsid:zoobank.org:pub:971811AE-DF72-47E9-AED9-DEE835D1D412  相似文献   

16.
《Journal of Natural History》2012,46(5):1311-1331
The current status of our understanding of cichlid intrafamilial relationships is investigated and novel data are presented resolving a basal trichotomy of the African and Neotropical radiations (Oliver, 1985). The claim that the African Cichlidae is non-monophyletic is supported and the little known Zairean genus Heterochromis is identified as the sistergroup of all other African and Neotropical Cichlidae combined. Throughout the study emphasis has been placed upon the resolution of the precise phylogenetic relationships of the enigmatic Neotropical genus, Cichla; a taxon whose placement has been thought critical for successful intra-familial analyses. Analysis of the evidence currently available argues strongly in favour of a close phylogenetic relationship between Cichla and the sisterpair, Crenicichla and Teleocichla. Given this phylogenetic scheme one of the most interesting aspects to arise is the striking morphological parallels between Cichla and many of its distantly related percoid relatives.  相似文献   

17.
《Journal of Natural History》2012,46(5):1167-1187
The zoeal and megalopal stages of Phimochirus roseus (Benedict, 1892) are described and illustrated from material reared under laboratory conditions. Although the vast majority of zoeae of this species pass through only four larval stages before the moult to megalopa, an occasional fifth stage has been observed. Phimochirus roseus differs in a number of morphological attributes from the only other species of Phimochirus whose larvae have been described. However, their shared features are sufficiently characteristic to confirm the distinctiveness of the genus and its general developmental homogeneity.  相似文献   

18.
《Journal of Natural History》2012,46(5):1077-1173
The Cassidininae of Australia are revised. The status of the subfamily is assessed and it is concluded that, as presently constituted, the Cassidininae is an artificial taxon. It is maintained here as a taxon of convenience (sensu lato) until the other sphaeromatid subfamilies can be reassessed, but a new diagnosis (sensu stricto) is given. The genus Cassidina is redescribed. Three new genera are established: Agostodina gen. nov. (type species: A. munta sp. nov.), Apemosphaera gen. nov. (type species: A. naranagi sp. nov.) and Discidina gen. nov. (type species: D. banawarra sp. nov.). New diagnoses are provided for the genera Cassidina Milne Edwards, Chitonopsis Whitelegge, Cassidinidea Hansen, Paracassidina Baker, Syncassidina Baker and Platysphaera Holdich and Harrison. The genus Dies is placed in synonymy with Cassidinidea and an annotated list is given of all species of the genus. The following new species (excluding the new type species) are described: Chitonopsis booyoolie, Agostodina munta, Paracassidina anasilla, P. bakeri, P. bamarook, P. bilbie, P. cervina, P. dama, P. fuscina, P. incompta, P. kutyo, P. munna, P. petala, P. prolata, P. wurrook and Cassidinidea korpie. Keys to the Australian genera and species are given.  相似文献   

19.
《Journal of Natural History》2012,46(9-10):601-613
In the present study, we review the genus Nippoptilia of Korea. In total, four species are recognized, including a new species, Nippoptilia distigmata sp. nov., and two new records, Nippoptilia cinctipedalis (Walker) and N. issikii Yano, for Korea. All the available information, such as distributional ranges and biology of each taxon, is provided. The keys to the genus Nippoptilia in Korea are provided, along with illustrations of external and genitalic characteristics.  相似文献   

20.
The gekkonid lizard genus Uroplatus is comprehensively reviewed for the first time. Six species are recognized—U. fimbriatus, U. sikorae, U. lineatus, U. ebenaui, U. alluaudi and U. guentheri—and their potential interrelationships are examined. Numerous bizzare morphological features, characteristic of the highly derived species U. fimbriatus, are found to be shared with other members of the genus, but are not universal for this taxon. Thus, while U. fimbriatus exhibits an overall morphology that has been employed in the past as justification for elevating the genus to monotypic familial status, this represents only an extreme of a continuum. U. guentheri and U. alluaudi are much less unusual in their morphological features. The potential biological roles of the more extreme features found within the genus are considered.  相似文献   

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