Phylogenetic relationships in West Mediterranean Scaritina (Coleoptera : Carabidae) inferred from mitochondrial COI sequences and karyotype analysis

The phylogenetic relationships of the West Mediterranean lineages of the su btribe Scaritina have been investigated by studying the mitochondrial cytoc hrome oxidase gene (COI) and the mitotic and meiotic chromosomes, including the localization of rDNA genes by fluorescence ill situ hybridization. The se sources of data are congruent and suggest the following conclusions: (1) the subgenus Parallelomorphus (genus Scarites) is a monophyletic group acc ording to molecular and karyotypic data, in agreement with its geographical distribution and morphological characters; (2) in the same genus, the subg enus Scallophorites seems to be monophyletic but includes two well-separate d lineages - one represented by Scarites buparius(Forster, 1771) and Scarit es occidentalis (Bedel, 1895) (both with multiple sex chromosomes), and one represented by Scarites hespericus (Dejean, 1831); (3) the nominal subgenu s Scarites s.s. represented by Scarites eurytus (Fischer, 1828), is cladist ically more closely related to subgenus Scallophorites than to subgenus Par allelomorphus; (4) Distichus planus (Bonelli, 1813) belongs to a distinct c lade that is well separated from Scarites, and shows more plesiomorphic sta tes of COI sequence and chromosome number. In addition, the presence of two autapomorphies, such as rDNA sites located in the X chromosome, and an A T rich intergenic spacer of about 120 bp between the stop codon of the COI gene and the tRNAleu, agree with the ranking of Distichus as a separate ge nus from Scarites.