A chromosomal analysis of three species of Timarcha (Coleoptera, Chrysomelidae, Chrysomelinae)

The karyotypes of three species of Timarcha Latreille, 1829 have been analysed. Timarcha (Metallotimarcha) metallica (Laicharting, 1781), has 18 + Xyp male meioformula and 2n = 38 chromosomes, similar to those found in the two species of subgenus Americanotimarcha Jolivet, 1948, in agreement with morphological and molecular phylogenetic grounds. Timarcha (Timarcha) carmelenae Petitpierre, 2013 displays 9 + Xyp and 2n = 20 chromosomes as in morphologically related Andalusian species, whereas Timarcha (Timarcha) parvicollis ssp. seidlitzi Kraatz, 1879 shows 11 + Xyp and 2n = 24 chromosomes, clearly differing from the previous species. These results are discussed in order to get an insight into the main trends of the chromosomal evolution in Timarcha.