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971.
The chironomid fauna of the Mediterranean region reviewed 总被引:1,自引:0,他引:1
From the Mediterranean countries, Italy, France (southern), Spain, Portugal, Morocco, Algeria, Tunisia, Lebanon, Syria, Turkey, Greece and Yugoslavia and according to published and as yet unpublished data, about 703 Chironomid species are known. 97 of the species are exclusive to the Mediterranean region. For three speciesCricotopus beckeri, Eukiefferiella bedmari andParatanytarsus mediterraneus a pointdistribution map is given.29 species listed with an Afrotropical distribution also reach into various parts of the Mediterranean area. As an example, a point-distribution map ofParatrichocladius micans is given. Seven species with a Panpalaeotropical distribution are known in the Mediterranean region. The great majority of the other 570 species (81%) most likely have a Palaearctic distribution. However, accurate distribution data of many species are as yet not available. This holds in particular for species with an assumed Southpalaearctic distribution. For chironomids of the Mediterranean fauna a differentiation into Circum- and West-Mediterranean subgroups is not yet possible. The Afrotropical species reach the Mediterranean region chiefly by the Nile valley. Nevertheless, some apparently relict Afrotropic species in the South of Morocco may suggest a West-African progression towards the Mediterranean. The Syrian-East African rift valley may also be considered as a migration path for West Palaearctic and especially Oriental chironomids into the Afrotropic region. 相似文献
972.
Timothy J. Lott Brian M. Burns Rosely Zancope-Oliveira Cheryl M. Elie Errol Reiss 《Current microbiology》1998,36(2):63-69
Nucleotide sequences of the internal transcribed spacer 2 (ITS2) regions were determined for 13 species within the genus
Candida, representing a collection of those species pathogenic for humans. No two species had identical sequences and the sizes of
ITS2 varied fourfold, representing an apparent continuous gradient of nucleotides. When present, sequence homologies were
observed in the 5′ end of ITS2, and many species exhibited more limited homologies within three known conserved domains found
in other yeasts. Cluster analysis of primary sequence revealed a concordance with a known taxonomic subfamily and suggests
that certain species within the genus form a similar grouping. A majority of species exhibited similar presumptive RNA secondary
structures, consistent with the hypothesis that these spacer regions are essential for correct processing of the 5.8S and
28S subunits.
Received: 14 April 1997 / Accepted: 22 July 1997 相似文献