Dissertation
A molecular phylogeny of the crane fly family Tipulidae (Diptera: Tipuloidea) and the evolution of their larval morphology and habitats
Doctor of Philosophy (Ph.D.), Drexel University
Dec 2024
DOI:
https://doi.org/10.17918/00010815
Abstract
The Tipulidae are a diverse lineage of crane flies with 4360 known species and a near-global distribution. Across the globe, most species feed on detritus, though their habitats are diverse. Larvae of Tipulidae can be found in fast flowing water, semi-aquatic habitat, drier soils, and even wood and moss. Despite this diversity and unique distribution of larval habitats, no modern molecular phylogenetic analysis has been completed with a large number of taxa. Here we reconstruct a comprehensive phylogeny of the family Tipulidae. Because we had no previously published phylogeny to use as a hypothesis, we chose to conduct a CO1 barcode analysis of 1954 species. The topology was vastly different from the relationships hypothesized in the taxonomic literature. Using this CO1 phylogeny as a guide we sampled 289 taxa for an Anchored Hybrid Enrichment study. The AHE analysis resulted in a fully resolved and highly supported tree that yielded 5 subfamilies. We recommend raising all Tipula subgenera to genus level and restricting Tipula to only those species previously placed in the subgenus Tipula. Further we recommend restricting Lunatipula to the clade containing the type species L. lunata and leaving Lunatipula s.l. unplaced. We constructed a larval trait database to examine the evolution of larval habitats and morphology. We used a 116-trait database and found one character along with habitat that had a high phylogenetic signal and low interaction among the traits. We reconstructed ancestral character state for these two traits and habitat. Additionally, we found 7 traits that significantly shared a phylogenetic signal with habitat. Finally, we selected 5 Tipulid fossils and used them to calibrate AHE phylogeny. We recovered a family origin slightly older than known fossils at about 170mya, and rapid speciation and divergence starting about 100mya and intensifying at 65mya. We found the ancestor to Tipulidae likely was semiaquatic and diverged from Cylindrotomidae in the Jurrasic. Larvae in specialized terrestrial, aquatic, moss, or wood habitat appear to have arisen in the last 50 million years and may follow climatic shifts.
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Details
- Title
- A molecular phylogeny of the crane fly family Tipulidae (Diptera: Tipuloidea) and the evolution of their larval morphology and habitats
- Creators
- Robert Thomas Conrow
- Contributors
- Jon K. Gelhaus (Advisor)Jason D. Weckstein (Advisor)
- Awarding Institution
- Drexel University
- Degree Awarded
- Doctor of Philosophy (Ph.D.)
- Publisher
- Drexel University; Philadelphia, Pennsylvania
- Number of pages
- x, 99 pages
- Resource Type
- Dissertation
- Language
- English
- Academic Unit
- Biodiversity, Earth, and Environmental Science (BEES); College of Arts and Sciences; Drexel University
- Other Identifier
- 991022019718304721