Thesis
Illuminating Apocephalus Coquillett (Diptera: Phoridae) parasitoid biology: host associations, detection of host identity from parasitoid tissue, and superparasitism
University of Iowa
Master of Science (MS), University of Iowa
Spring 2025
DOI: 10.25820/etd.008018
Abstract
Association with different hosts can lead to reproductive isolation and speciation for insects. The phorid fly, Apocephalus antennatus Malloch, is classified as a single, widely dispersed, and highly generalist species that is known to parasitize many different genera of fireflies (Lampyridae). However, when other putatively generalist Apocephalus Coquillett have been analyzed with genetic markers they have proved to consist of several cryptic specialist species, each with a more limited host range. To test for hidden diversity related to host association in this widespread phorid species, I collected parasitized Lampyridae species from Costa Rica and across the eastern half of North America from May-August 2024. I extracted DNA and amplified a single mitochondrial gene and a single nuclear gene. I then sequenced the genes with an Oxford Nanopore MinION and analyzed genetic sequences alongside host associations and morphology to delimit putative species. My results do not support host associated differences in Apocephalus antennatus in North America. Evidence instead suggests a single species using several different firefly hosts, both nocturnal and diurnal. Thus, A. antennatus appears unusual among other Phoridae in being able to attack multiple different host species of several niches. This finding is an important step in understanding why host-associated differentiation (HAD) appears in certain phorid species and does not in others. I also report previously unknown occurrences of superparasitism in Apocephalus and demonstrate the efficacy of nanopore sequencing in identifying hosts of phorid parasites using only DNA extracted from pupal or adult phorids.
Details
- Title: Subtitle
- Illuminating Apocephalus Coquillett (Diptera: Phoridae) parasitoid biology: host associations, detection of host identity from parasitoid tissue, and superparasitism
- Creators
- Mattie Gose
- Contributors
- Andrew Forbes (Advisor)Maurine Neiman (Committee Member)Brian Brown (Committee Member)
- Resource Type
- Thesis
- Degree Awarded
- Master of Science (MS), University of Iowa
- Degree in
- Integrated Biology
- Date degree season
- Spring 2025
- DOI
- 10.25820/etd.008018
- Publisher
- University of Iowa
- Number of pages
- viii, 117 pages
- Copyright
- Copyright 2025 Mattie Gose
- Language
- English
- Date submitted
- 04/24/2025
- Description illustrations
- color illustrations
- Description bibliographic
- Includes bibliographical references (page 31-40).
- Public Abstract (ETD)
For insects, associations with different hosts can lead to the origin of new species. While some insects attack a broad range of hosts, others specialize on only one or a few. Genetic analysis of generalist insects can reveal cryptic species that look the same yet are specialized on different hosts and are reproductively isolated. The phorid fly, Apocephalus antennatus Malloch, is classified as one species that attacks many different firefly hosts and appears to be more generalist than other related species. The goal of this study is to test whether A. antennatus using different hosts are actually different species.
To test for the presence of hidden diversity related to host association, I collected fireflies from eastern North America and Costa Rica. I used host associations, genetic, and morphological analysis to define species. My results do not support the presence of host associated differences and instead imply that A. antennatus is truly one generalist species that parasitizes several different firefly hosts. This finding is an important step in understanding why host-associated differentiation (HAD) appears in certain phorid species and does not in others. In addition, I present evidence that multiple A. antennatus females will lay eggs in the same host. I also demonstrate that nanopore sequencing can be used to identify the host of a phorid parasite using only DNA extracted from the phorid sample.
- Academic Unit
- Biology
- Record Identifier
- 9984830825602771
Metrics
1 Record Views