CAREER: Microcaddisflies, Morphology, and Modern Molecular Methods: Using Collections-Based Research to Establish the Microcaddisfly Phylogeny and Create Educational Opportunities

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

Caddisflies (Trichoptera) are an ecologically-important order of aquatic insects that contribute to the processing of nutrients and the flow of energy through food webs in freshwater habitats. Due to their varying levels of tolerance to pollution and disturbance, caddisflies are also one of the primary invertebrate groups used for biological monitoring of water quality. The family Hydroptilidae, known as the “microcaddisflies” due to their small body size of 1.5-5 mm, are an extremely diverse family of caddisflies with over 2,600 known species occurring around the world and potentially many 100s of undescribed species. Microcaddisflies display a wide range of ecological, morphological, and behavioral diversity and occur in interesting distributional patterns around the world, none of which has been explored in the context of the evolutionary relationships within the family. Current understanding of the microcaddisfly evolutionary history suffers from a lack of statistically-supported analyses, inconsistent use of morphological features, and very little inclusion of molecular data. This research will focus on reconstructing the evolutionary history of this diverse, yet under-studied, group of insects. The broader impacts of this research include the training of one PhD student and multiple undergraduates in modern taxonomy and systematics; a new course in the Museum Studies program that will introduce students to the importance of insect diversity, provide hands-on experience with specimen collection and curation, and increase awareness of related legal and ethical issues surrounding collections; and a noncredit course exploring insect biodiversity to be offered to a community of lifelong learners. A combined approach of molecular and morphological data, applied for the first time with modern statistical methods and analytical techniques, will be used to assess the evolutionary history of the microcaddisflies (Trichoptera: Hydroptilidae), a diverse yet under-studied taxon. Researchers will (1) infer the first total-evidence phylogeny of the family Hydroptilidae, which will include the first morphological assessment of homology across the family and the first molecular dataset to cover the entire family using targeted enrichment techniques; (2) use the constructed phylogeny to shed light on subfamilies and genera in need of taxonomic updates, revisionary monographs, and new species descriptions; and (3) determine biogeographic and divergence time estimates that will add to a more detailed profile of hydroptilid evolutionary history. These approaches will provide new insight into hydroptilid phylogenetics and allow for future research on character evolution within Hydroptilidae, diversification and speciation rates relative to the rest of Trichoptera, and larger questions of evolution applied across the order. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.