Insights into the subgenera Chrysolina s. str. and Rhyssoloma Woll. of Chrysolina Mots. (Coleoptera: Chrysomelidae: Chrysomelinae)

The taxonomic position of Chrysolina costalis and C. wollastoni in the subgenera Chrysolina s. str. or Rhyssoloma is ambiguous. Recently, they have moved from the former to the latter subgenus, by taking four morphological characters. However, C. (Rhyssoloma) fragariae, the type species of this subgenus, is clearly distinguished with regard to the two previous species, from other morphological features, also the male karyotype of 2n=24(Xyp) instead of 2n=23(X0) chromosomes, and mainly in the DNA molecular phylogenetic trees where C. costalis and C. wollastoni appear in the same highly supported clade with C. bankii, another species of the Chrysolina s. str. subgenus. Therefore, the subgenus Rhyssoloma should be maintained as monotypic with C. fragariae as its unique species like it was before. [Cover by Katja Schulz from Washington, D. C., USA - Leaf Beetle eating Common Plantain, no change made, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=49953690]