19th Annual Student Research Conference
Science
Holey Rocks: Shale-Boring Insects in the Chariton River
Nicholas C. Mueth* and Jessica R. Hejnal
Dr. George L. Shinn, Faculty Mentor
The Chariton River near Yarrow, Missouri is home to a wide variety of organisms (fish, crustaceans, insects, and mollusks), which utilize the river-bottom's loose rocks and sediments for shelter. Among these is an unusual species of larval insect that has found a viable niche by boring extensively into shale outcroppings on the river bed. The larvae belong to the family Chironomidae, within the order Diptera; the adults are flies commonly referred to as midges. Distinctive head structures, examined by both light microscopy and scanning electron microscopy, reveal them to be members of the widespread genus Axarus. Our ongoing study examines the detailed structure of the burrows, how growing larvae enlarge their burrows, and how the burrowing habit relates to feeding. The closely spaced holes created by the larvae appear to enhance erosion of both the shale deposits in which they live and of overlying limestone cap-rocks.
Keywords: Axarus, Chariton River, shale, burrowing, rock-boring, Chironomidae
Topic(s):Biology
Presentation Type: Poster
Session: 60-57
Location: OP Lobby and Atrium
Time: 4:15