Species delineation and description in Aethaloptera Brauer genus by phallic head (Trichoptera, Hydropsychidae, Macronematinae)

Abstract

Taxonomy of the “widely distributed and highly varying species” in the small Aethaloptera genus was questioned long ago. Relying on the macro morphology, detectable by the routine resolution of the stereomicroscope, these species look very similar. However, applying the higher resolution of compound microscope with focusing on profile stability, significant shape divergences have been recognised in the fine structure of the speciation trait that is in the much specialised head structure of the phallic organ. The ancestral prototype of caddisfly genitalia is highly modified in the Hydropsychidae family. The hydropsychid prototype is further organised in the macronematine Aethaloptera genus: the abbreviated primordial genital structures of Hydropsychidae family are retracted into the invaginated tip of the phallotheca with apomorphic organisation of complexity by reduction or simplification, a complexity integrated by incremental subtraction. Examining the fine phenomics of the phallic head we have tripled the species number in this small genus and delineated altogether 12 species. We expect many more species to be collected and distinguished in this neglected genus by the fine structure of this speciation trait. Here we established two new species groups: Aethaloptera dispar new species group and A. meyi new species group and described five new species: Aethaloptera felalla, A. karima, A. malickyi, A. meyi and A. wellsi spp. nov.

Keywords

• Speciation trait
• fine phenomics
• incremental subtraction
• new Aethaloptera species