The First Cytogenetic Report on Laena reitteri Weise, 1877 (Coleoptera, Tenebrionidae, Lagriinae) with Notes on Karyotypes of Darkling Beetles

Department of Zoology, Comenius University, Mlynská dolina B-1, 842-15 Bratislava, Slovakia.
Folia Biologica (Impact Factor: 0.88). 02/2008; 56(3-4):213-7. DOI: 10.3409/fb.56_3-4.213-217
Source: PubMed


The karyotype structure of Laena reitteri is described for the first time. The chromosome number 2n = 18+1-3B and meioformula n(male) = 8+Xy+1-3B deviates from the modal tenebrionid number. The karyotype exhibits low variation in morphology and length. The diploid set consists of four long (subtelocentric and acrocentric), twelve medium-sized acrocentric autosomes and sex heterochromosomes Xy. The X chromosome is submetacentric, while the y is acrocentric and the smallest element of the set. On mitotic and meiotic plates 1-3 small additional elements are also visible, and probably represent B-chromosomes. The NORs are very active at mitotic prophase and early meiotic stages.

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    • "To characterize the molecular composition of the constitutive heterochromatin, we stained the chromosomes with DNA-specific fluorochromes CMA 3 (the antibiotic chromomycin A 3 ) and DAPI (4'-6-diamidino-2-phenylindol) that selectively stain GC-rich and AT-rich DNA fragments, respectively (Schweizer 1976; Donlon and Magenis 1983). Staining with fluorochromes was performed after C-banding procedure as described above. "
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