The Chromosomes of Lepturinae (Coleoptera: Cerambycidae) II. A study of 8 more species, with focus on Desmocerus palliatus

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Cytogenetics of Oryctes nasicornis

The chromosomes of specimens of Oryctes nasicornis from three locations in France and two locations in Greece were studied. All karyotypes have an X-Y-autosome translocation: 18, neoXY. Two male specimens from France (subspecies nasicornis) displayed an unusual behaviour of their meiotic chromosomes in 30–50% of spermatocytes, with asynapsis at pachynema, premature bivalent and chromosome split at metaphases I and II. The karyotypes remained balanced at metaphase I, but not at metaphase II. These particularities mimic the meiotic behaviour of B chromosomes and question about their existence, reported earlier in Spanish specimens. Due to the variable character of B chromosomes, complementary analyses are needed. To our knowledge, such meiotic particularities have not been described, beside cases of infertility. In specimens from Corsica (subspecies laevigatus) and Greece (subspecies kuntzeni), all spermatocytes I and II had a normal appearance. The meiotic particularity may thus be limited to male specimens from subspecies nasicornis

Phylogenetic inferences of Atelinae (Platyrrhini) based on multi-directional chromosome painting in Brachyteles arachnoides, Ateles paniscus paniscus and Ateles b. marginatus

We performed multi-directional chromosome painting in a comparative cytogenetic study of the three Atelinae species Brachyteles arachnoides, Ateles paniscus paniscus and Ateles belzebuth marginatus, in order to reconstruct phylogenetic relationships within this Platyrrhini subfamily. Comparative chromosome maps between these species were established by multi-color fluorescence in situ hybridization ( FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and four previously analyzed species from all four Atelinae genera were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 82 discrete chromosome characters. The results confirmed that Atelinae represent a monophyletic clade with a putative ancestral karyotype of 2n = 62 chromosomes. Phylogenetic analysis revealed an evolutionary branching sequence \{Alouatta \{Brachyteles \{Lagothrix and Ateles\}\}\} in Atelinae and \{Ateles belzebuth marginatus \{Ateles paniscus paniscus \{Ateles belzebuth hybridus and Ateles geoffroyi\}\}\} in genus Ateles. The chromosomal data support a re-evaluation of the taxonomic status of Ateles b. hybridus. Copyright (C) 2005 S. Karger AG, Basel

Karyotype diversity suggests that Laonastes aenigmamus (Laotian rock rat) (Rodentia, Diatomyidae) is a multi-specific genus

International audienceLaonastes aenigmamus (Khanyou) is a recently described rodent species living in geographically separated limestone formations of the Khammuan Province in Lao PDR. Chromosomes of 21 specimens of L. aenigmamus were studied using chromosome banding as well as fluorescent in situ hybridization (FISH) techniques using human painting, telomere repeats , and 28S rDNA probes. Four different karyotypes were established. Study with human chromosome paints and FISH revealed that four large chromosomes were formed by multiple common tandem fusions, with persistence of some interstitial telomeres. The rearrangements separating the different karyotypes (I to IV) were also reconstructed. Various combinations of Robertsonian translocations or tandem fusions involving the same chromosomes differentiate these karyo-types. These rearrangements create a strong gametic barrier, which isolates specimens with karyotype II from the others. C-banding and FISH with telomere repeats also exhibit large and systematized differences between karyotype II and others. These data indicate an ancient reproductive separation and suggest that Laonastes is not a mono-specific genus

Molecular cytotaxonomy of primates by chromosomal in situ suppression hybridization

A new strategy for analyzing chromosomal evolution in primates is presented using chromosomal in situ suppression (CISS) hybridization. Biotin-labeled DNA libraries from flow-sorted human chromosomes are hybridized to chromosome preparations of catarrhines, platyrrhines, and prosimians. By this approach rearrangements of chromosomes that occurred during hominoid evolution are visualized directly at the level of DNA sequences, even in primate species with pronounced chromosomal shuffles

Chromosomal and genetic characterization of four Caribbean Prioninae (Coleoptera: Cerambycidae) species with notes on biogeography

Chromosomes of four rare and localized Caribbean Prioninae (Coleoptera: Cerambycidae) species were analysed. All have 26, XY karyotypes. Those of Solenoptera canaliculata (Solenopterini) from Guadeloupe nearby islands Les Saintes and Marie-Galante and S. quadrilineata from Martinique look similar. They have a single pair of sub-metacentric autosomes. The karyotype of S. touroulti from St. Lucia has three sub-metacentric pairs. It appears closer to that of Hovorodon maxillosum (Mallodontini) from Marie-Galante which has ten sub-metacentric pairs. The CO1 gene sequence, taking two European species Aegosoma scabricorne (Prioninae: Aegosomatini) and Ergates faber (Prioninae: Ergatini) as external groups was analysed in S. canaliculata and S. quadrilineata. In spite of their karyotype similarity, their CO1 genes differ by a strong accumulation of mutations. Thus, either chromosomal or genetic data confirm the species status of the three closely related Solenoptera species. Ten different CO1 haplotypes are found among the 21 specimens of S. canaliculata studied from les Saintes and Marie-Galante. Both different haplotypes were found in each island and identical haplotypes were found in different islands. Hence, the gene flow was not interrupted. Biogeographical parameters favor the hypothesis that repeated passages between islands were made possible by floating trunks, principally from Les Saintes to Marie-Galante