Cladistic analysis of Phasiinae (Diptera: Tachinidae), based on morphological characters

Author(s)

Rodrigo de Vilhena Perez Dios

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2020-01-28

Examining board members

Silvio Shigueo Nihei; Carlos José Einicker Lamas; Catia Antunes de Mello Patiu; Cristiano Feldens Schwertner

• Advisor: Silvio Shigueo Nihei

Abstract

Among the highly diverse class Insecta, the order Diptera, comprising flies and mosquitoes, is one of the most diverse. The order also presents an enormous diversity of life habits and morphology variation in all its life stages. Tachinidae, one of the Diptera families with the highest number of species, are known for its parasitoid habits of other Arthropoda. Phasiinae, a Tachinidae subfamily, is historically known for being parasitoid of heteropteran bugs and therefore its importance for biological control, as many of its hosts are agricultural pests. Phasiinae is currently classified into 103 genera with ca 620 species worldwide. Despite being the smaller Tachinidae subfamily, they present a wide range of morphological variation, mainly in the terminalia. The subfamily systematics was studied recently with molecular data, but some questions remain regarding its internal relationships. We propose a phylogenetic analysis of Phasiinae using 183 morphological characters, sampling 72 genera from all tribes and all zoogeographical regions. Phasiinae is corroborated as monophyletic, as well as most of its tribes; some taxonomic changes were made and the subfamily classification updated following the phylogenetic hypothesis. The basal relationships of Phasiinae and between some tribes still have uncertainties, and further studies are required. During the morphological study we were able to explore more deeply the less known female terminalia of Phasiinae. A diagnosis for the female terminalia of each Phasiinae tribe is presented, as well as some new homologies proposed and discussed. Combining both chapters, we have also further explored the evolution of the two main oviposition strategies in the subfamily and their associated morphology: the strategy of piercing the host and the strategy of laying large planoconvex eggs externally on the host. Both apparently evolved more than once in Phasiinae. The present study can contribute to new systematic studies, as well as further allowing host-parasite evolutionary studies (AU)

• FAPESP's process: 16/12441-0 - Comparative morphological study and cladistic analysis of Phasiinae (Diptera: Tachinidae) based on morphological characters
• Grantee: Rodrigo de Vilhena Perez Dios
• Support Opportunities: Scholarships in Brazil - Doctorate