28th Annual Student Research Conference
Crayfish Sex: How Sperm Are Packaged for Mating by Orconectes immunis
Sean M. Simpson* and Grace E. Kenney
Dr. George L. Shinn, Faculty Mentor
Crayfish mating occurs days, weeks, or months before sperm are used in fertilization. We have used scanning electron microscopy and light microscopy to elucidate how sperm are packaged to survive long-term storage within the seminal receptacles of females. The males sperm duct produces an elaborate sperm column comprising a complex, multilayered wall of viscous secretions around a central core of sperm evenly dispersed in a gelatinous matrix. When exposed to water, the gelatinous matrix swells and the sperm go through an irreversible fertilization reaction. Thus, long-term storage requires that sperm be protected from water. Males use specialized legs called gonopods to transfer the sperm column into the seminal receptacle of females. The viscous wall materials separate from the sperm and gelatinous matrix forming a sperm plug. This blocks the entrance to the seminal receptacle, preventing exposure of sperm to water. This probably also prevents sperm removal by other males.
Keywords: crayfish, mating, sperm column, gonopod, seminal receptacle, Orconectes, sperm plug
Topic(s):Biology
Presentation Type: Poster
Session: 3-4
Location: GEO-SUB
Time: 3:30