Wyniki wyszukiwania

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Syntopic taxa in the Sylvia cantillans species complex

100%

Brambilla M., Quaglierini A., Reginato F., Vitulano S., Guidali F.

Acta Ornithologica

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2008

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tom 43

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nr 2

217-220

Distributional relationships among closely related taxa can provide key information about the levels of their reproductive isolation or compatibility, and thus the stage of speciation process. Here, we present new information on the sites where two taxa traditionally considered as subspecies of the Subalpine Warbler Sylvia cantillans, S. c. cantillans and S. (c.) moltonii, breed sympatrically in mainland Italy. We analyse geographic distribution and behaviour as well as other characteristics shown by these warblers in the areas of contact. The distributional pattern shown by these taxa, which is partly sympatric with syntopic breeding, and the apparent lack of interbreeding, strongly suggest that they behave as different species, confirming previous findings about genetic divergence and differential song perception.

2

Post-zygotic reproductive isolation in two populations of the African vlei rat Otomys irroratus

100%

Pillay N., Willan K., Meester J.

Acta Theriologica

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1995

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tom 40

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nr 1

Post-zygotic reproductive isolating mechanisms between two chromosomally distinct, allopatric Otomys irroratus (Brants, 1827) populations (Kamberg and Karkloof) were studied in the laboratory by means of breeding trials, and by comparing the postnatal development of young of intrapopulation and interpopulation pairs. In contrast to the 100% breeding success of intrapopulation pairs, fewer than half of the interpopulation pairs produced young, and overall reproductive performance of these pairs was reduced. Furthermore, fitness of hybrids was dramatically impaired, as indicated by increased pre-weaning mortality, and inhibited growth in respect of body mass (postnatal development), as well as almost complete sterility (backcross and hybrid-cross matings) of surviving young. The results indicate the existence of chromosomal and/or genetic incompatibility between the two populations. The presence of a tandem fusion in the Kamberg karyotype is thought to be particularly significant in causing hybrid sterility, and the Kamberg population may be regarded as an incipient sibling species.

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Chromosomal and genic mechanisms of reproductive isolation: the case of Suncus murinus

100%

Rogatcheva M. B., Aulchenko Y. S., Oda S. I., Zhelezova A. I., Serova I. A., Axenovich T. I., Borodin P. M.

Acta Theriologica. Supplement

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2000

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tom 45

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nr 1

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Evolutionary relationships of Ctenomys [Rodentia: Octodontidae] from Argentina, based on penis morphology

100%

Balbontin J., Reig S., Moreno S.

Acta Theriologica

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1996

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tom 41

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nr 3

Analyses of qualitative and quantitative variation in bacula and soft parts of the glans penis of 13 species of Ctenomys Blainville, 1926 from Argentina were used to suggest systematic and evolutionary relationships. The 13 species can be divided into spike-bearing {C. australis, C. azarae, C. porteousi, C. rionegrensis, and C. talarum) and spiny bulb-bearing species {C. dorbignyi, C. pearsoni, C. perrensi, C. roigi, Ctenomys sp. from Curuzú Laurel, Ctenomys sp. from M. F. Mantilla, and Ctenomys sp. from San Roque). Ctenomys yolandae is unique because it shows both spikes and spiny bulbs. In addition to spikes and spiny bulbs, some populations of C. pearsoni, C. talarum, and C. yolandae had a new structure, an inner sac of the intromittent sac. The most frequent pattern of occurrence of spikes or spiny bulbs was 1-1 (one at each side of the urethra), an ancestral character state in caviomorphs. Variation in bacular dimensions was limited and differences among species were small, with the exception of C. pearsoni. This species showed a significantly short baculum with a wide base. Sperm and penial morphology suggests that C. talarum is the most plesiomorphic and C. yolandae the most derived species of this group. The pattern of geographic variation among these 13 species rejects the hypothesis of penis morphology contributing to reproductive isolation. Ctenomys pearsoni is the only species with some evidence of reproductive isolation resulting from penis morphology.

5

Postzygotic reproductive isolation between mendelian species of European water frogs

100%

Berger L., Uzzell T., Hotz H.

Zoologica Poloniae

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1994

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tom 39

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nr 3-4

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Genetic structure of a Japanese allotetraploid loach of the genus Cobitis [Osteichthyes, Cobitidae]

80%

Kitagawa T., Yoshioka M., Kashiwagi M., Okazaki T.

Folia Biologica

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2003

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tom 51

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nr Suppl.

7

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Deroceras panormitanum and congeners from Malta and Sicily, with a redescription of the widespread pest slug as Deroceras invadens n. sp.

71%

Reise H., Hutchinson J. M. C., Schunack S., Schlitt B.

Folia Malacologica

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2011

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tom 19

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nr 4

The name Deroceras panormitanum is generally applied to a terrestrial slug that has spread worldwide and can be a pest; earlier this tramp species had been called Deroceras caruanae. Neither name is appropriate. The taxonomic descriptions apply to a species from Sicily and Malta. This true D. panormitanum and the tramp species are distinct in morphology and mating behaviour. For instance, the penial caecum of D. panormitanum is more pointed, everting faster at copulation. The size of the penial lobe varies considerably In preserved specimens but is always prominent at copulation. D. panormitanum is distinct from the Maltese endemic Deroceras golcheri, but a phylogeny based on mtDNA COI sequences implies that they are more closely related than is the tramp species. D. golcheri has a still closer counterpart on Sicily, but we leave the taxonomy of this “species X” unresolved. In interspecific crosses, D. panormitanum may transfer sperm to the partner’s sarcobelum whereas the partner fails to evert its penis (D. golcheri) or to transfer sperm (the tramp species). Names previously applied to the tramp species originally referred to D. panormitanum or are otherwise invalid, so it is here formally redescribed as D. invadens. Deroceras giustianum Wiktor, 1998 is synonymised with D. panormitanum.

Ograniczanie wyników

Syntopic taxa in the Sylvia cantillans species complex

Post-zygotic reproductive isolation in two populations of the African vlei rat Otomys irroratus

Chromosomal and genic mechanisms of reproductive isolation: the case of Suncus murinus

Evolutionary relationships of Ctenomys [Rodentia: Octodontidae] from Argentina, based on penis morphology

Postzygotic reproductive isolation between mendelian species of European water frogs

Genetic structure of a Japanese allotetraploid loach of the genus Cobitis [Osteichthyes, Cobitidae]

Deroceras panormitanum and congeners from Malta and Sicily, with a redescription of the widespread pest slug as Deroceras invadens n. sp.