Evolution of the skeleton and musculature of the male genitalia in the family lycaenidae (Lepidoptera): II. Infratribe Polyommatina Swainson, 1827

Abstract

Skeleton and musculature of valvae were examined in 19 species from the section Polyommatus (Lepidoptera, Lycaenidae) revised by Balint and Johnson (1997). Functional organization of male genitalia in the section Polyommatus was shown to be relatively constant. Significant interspecific variation of the skeleton and muscles was found only in the structure of valvae. During their evolution, the valvae became elongated, the costal torsion and longitudinal medial fold appeared on their medial wall, the subcostal groove was formed, and the intravalval muscle differentiated into two muscles forming a chiasma. This muscular chiasma was formed at least twice in the evolution of the group, in Polyommatus Latreille, 1804 + Aricia [Reichenbach], 1819 and in Plebeius Kluk, 1802. The genus Chilades Moore, [1881] is the least advanced as concerns the functional organization of the valvae. The genera Polyommatus and Aricia are the most advanced and constitute a sister pair. The intermediate position is occupied by Plebeius Kluk, 1802 and probably Madeleinea Balint, 1993. The genus Albulina Tutt, 1809 is a compound taxon, its species occupying an intermediate position between Polyommatus and Aricia on the one hand, and Plebeius on the other hand. With a sole exception, they are characterized by a plesiomorphic state of the valval musculature that does not allow their mutual phylogenetic relations to be evaluated consistently. The only examined species of the genus Agriades Hubner, [1819], A. glandon (De Prunner, 1798), also possesses undifferentiated musculature, but according to the characters of the vaginal area, its females are close to the branch Polyommatus + Aricia.