Karyotype of South American pampas ofPseudalopex gymnocercus (Carnivora,Canidae)

Summary The karyotype of the pampas fox has 2n=74 and a NF=76. Except forChrysocyon brachyurus, 2n=74 is a common diploid number for the South American Canidae. This number is higher than in theVulpes group and lower than in the group of the typicalCanis. No marker chromosomes are present in the South American Canidae.     

Chromosomes of South American Bufonidae (Amphibia anura)

Resumen Se estudiaron los cariotipos de ocho especies de Bufonidae sudamericanos:B. arenarum, B. ictericus ictericus, B. paracnemis, B. marinus, B. crucifer, B. granulosus d'orbignyi, B. granulosus fernandezae andB. spinulosus. En todas las especies se encontraron 2n = 22 chromosomas. No se encontró en el macho, ningun par heteromórfico, ni bivalente con caracteristicas y comportamiento que indicara la presencia de cromosomas sexuales.     

Zone electrophoretic studies on lactate dehydrogenase isoenzymes in South American Cichlids (Teleostei,Percomorphi)

Zusammenfassung Ein Vergleich der elektrophoretischen Mobilitäten der Laktatdehydrogenasen A₄ (Skelettmuskel), B₄ (Herz) und E₄ (Retina) zeigt bei 7 Arten der GattungCichlasoma weitgehende Übereinstimmungen. 10 Arten anderer Gattungen südamerikanischer Cichliden weisen, verglichen mit der GattungCichlasoma, zunehmende Divergenz der Isoenzymmuster auf. Es wird vermutet, dass sich hierin die phylogenetische Verwandtschaft der Gattungen widerspiegelt. Die auf Grund der Übereinstimmungen in LDH-Isoenzymmustern ermittelten phylogenetischen Zusammenhänge decken sich weitgehend mit den Beziehungen, die durch vergleichendmorphologische Untersuchungen aufgezeigt wurden. Das methodische Vorgehen scheint geeignet, taxonomische Beziehungen zu ergänzen, die durch klassische Kriterien dargelegt wurden

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The technical assistance of Mrs.Evelyne Perriard is gratefully acknowledged.     

Chromosome complement of tenrecs,Centetes ecaudatus (Order Insectivora,Class Mammalia)

Résumé Dans les leucoyctes en culture de 7 TenrecsCentetes ecaudatus (4 mâles et 3 femelles) provenant de la République Malgache, l'auteur a compté 38 chromosomes et constaté que les sexes ont un caryocyte distinct. C'est la première étude faite sur les chromosomes d'un représentant de la famille des Tenrecidae (Insectivores).

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Skin fibroplast cells were cultured fromCentetes ecaudatus (Animal No. 2). These cells gave a count of 38 chromosomes. Using the same techniques as above, whole blood cultures of the related tenrec,Hemicentetes semispinosus G. Cuvier, were counted. Preliminary studies indicate 38 chromosomes for this speices.     

Karyotypes of seven species of bats from Thailand (Chiroptera,Mammalia)

Summary Karyotypes ofMyotis siligorensis, Myotis mystacinus, Pipistrellus pulveratus, Tylonycteris robustula, Miniopterus schreibersi fuliginosus, Hipposideros fulvus andAselliscus stoliczkanus from Thailand are investigated.Acknowledgment. The authors are very grateful to Dr N. Ratanawarabhan, Mrs S. Sittilert, P. Noonpakdee and S. Kuanchalern of Thailand Institute of Scientific and Technological Research for their valuable advice and assistance during our field survey in Thailand.     

Caryotypes de quelques hybrides interspécifiques dePitymys (Mammalia,Rodentia)

Summary The Robertsonian polymorphism ofPitymys subterraneus involves only 1 pair of metacentric autosomes. The crosses of forms with 52, 53 and 54 chromosomes do not show any differences in their reproductive rate. So a single autosome trivalent does not affect the fecondity. Many hybrids have been obtained betweenP. subterraneus (2N=52 or 54) andP. multiplex (2N=48) with 50 or 51 chromosomes, respectively. Even with a heterogenous karyotype they are not entirely sterile. 2 progeny were produced from back-crosses. The 2 parental species seem to result from recent speciation. Only fecondation or embryogenesis occurs in crossingP. duodecimcostatus withP. subterraneus orP. multiplex. The chromosome complement of 1 hybrid embryo ofP. duodecimcostatus (2N=62)×P. multiplex (2N=48) has been studied showing 55 chromosomes.P. duodecimcostatus appears to belong to a more distant evolutionary group.     

Karyotypes of seven species of bats from Thailand (Chiroptera, Mammalia)

Karyotypes of Myotis siligorensis, Myotis mystacinus, Pipistrellus pulveratus, Tylonycteris robustula, Miniopterus schreibersi fuliginosus, Hipposideros fulvus and Aselliscus stoliczkanus from Thailand are investigated.     

Goniothalamicin and annonacin: Bioactive acetogenins fromGoniothalamus giganteus (Annonaceae)

Summary Using brine shrimp lethality for activity-directed fractionation, goniothalamicin (I), a new tetrahydroxy-mono-tetrahydrofuran fatty acid -lactone (acetogenin), has been isolated from ethanolic extracts of the stem bark ofGoniothalamus giganteus Hook. f., Thomas (Annonaceae). This novel compound was found to be cytotoxic and insecticidal and inhibited the formation of crown gall tumors on potato discs. Annonacin (II), the only other reported mono-tetrahydrofuran acetogenin, was also isolated; the previously reported 9ASK (astrocytoma reversal) activity ofII was confirmed, andII is now also found to be weakly active against 3PS murine leukemia.     

Chromosomes of some Asian and South American squirrels (rodentia: Sciuridae)

Zusammenfassung Chromosomensätze verschiedener Sciurinae sind:Sciurus anomalus (2n=40),S. granatensis (2n=42),Callosciurus flavimanus (2n=40),Dremomys rufigenis (2n=38) undMenetes berdmorei (2n= 62). Ein Vergleich mit früher beschriebenen Sciurinae-Karyotypen ergibt als ursprünglich diploide Sätze 38–40, Spaltung, sowie Fusion zu grösseren und kleineren2n's führend.     

Gigantecin: A novel antimitotic and cytotoxic acetogenin,with nonadjacent tetrahydrofuran rings,fromGoniothalamus giganteus (Annonaceae)

Summary Gigantecin (I), a novel tetrahydroxy-di-tetrahydrofuran fatty acid -lactone (acetogenin), was isolated from an ethanolic extract of the stem bark ofGoniothalamus giganteus Hook. f., Thomas (Annonaceae), by means of activity-directed fractionation (brine shrimp lethality test). This new compound is extremely cytotoxic to human tumor cells, inhibits crown gall tumors on potato discs, and is active in an assay designed to detect antimitotic agents (9 ASK).     

New evidence of a 38-chromosomes karyotype in South American populations of the roof rat,Rattus Rattus L. (rodentia,muridae)

Resumen En dos poblaciones deRattus rattus, una de Mehuin (Valdivia, Chile) y otra de Capripe (Monagas, Venezuela), se encontró un cariotipo de 2n=38 cromosomas en todos los individuos estudiados. Este cariotipo corresponde al que presentan en forma monomórfica otras poblaciones de la rata negra de América del Sur y de Italia, y diffiere del cariotipo normal de la especie, que es de 42 cromosomas. Se postula que las distintas poblaciones sudamericans deRattus rattus deben haber invadido el Continente, acompañando al hombre, en distintas irrupciones, a partir de una forma de 38 cromosomas de origen mediterráneo.