Two New Species of Taygetina with a Possible Case of 'Juxta Loss' in Butterflies (Lepidoptera: Nymphalidae: Satyrinae)

The male genitalic characters of Hexapoda are well known for their great taxonomic and systematic value. Despite insect male genitalia displaying large diversity, variation, and modification across orders, some structures are consistently present, and such characters can serve as the basis for discussion regarding homology. In the order Lepidoptera, a male genitalic structure widely known as the 'juxta' is present in many taxa and absence or modification of this character can be phylogenetically informative at the generic or higher level. We here focus on the systematics of the so-called 'Taygetis clade' within the nymphalid subtribe Euptychiina, and report an unusual case of 'juxta loss' in a single species, Taygetina accacioi Nakahara & Freitas, n. sp., a new species from Brazil named and described herein. Additionally, we describe another west Amazonian Taygetina Forster, 1964 species, namely Taygetina brocki Lamas & Nakahara, n. sp., in order to better document the species diversity of Taygetina. Our most up-to-date comprehensive molecular phylogeny regarding 'Taygetis clade' recovered these two species as members of a monophyletic Taygetina, reinforcing the absence of juxta being a character state change occurring in a single lineage, resulting in an apomorphic condition, which we report here as a rare case in butterflies (Papilionoidea).