Large sperm-bundles in Homoptera insects

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 11640636
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 生態
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: HAYASHI Fumio Tokyo Metropolitan University, Department of Biology, Assistant Professor, 理学(系)研究科(研究院), 助手 (40212154)
• Project Period (FY): 1999 – 2000
• Keywords: sperm / mating behaviour / nuptial gift / multiple mating

Research Abstract

In some insect species, sperm are bundled after spermatogenesis and so transferred to the female. The function of such a bundle of sperm remains unknown. In this study, sperm of 29 species of Cicadomorpha and 12 species of Fulgoromorpha belonging to the infraorder Auchenorrhyncha (Homoptera) were observed. Sperm in the families Cicadidae, Aphropholidae and Cicadellidae attached at their tips to a rope- or rod-like hyaline material and form large bundles; however, sperm of the other families did not. The hyaline material of the sperm-bundles was digested with trypsin treatment, suggesting it proteinous. Sperm-bundles transferred to the female were broken down in a bursa copulatrix (ejaculate receiving organ) ; where sperm were released from the bundles and removed into a spermatheca (sperm storage organ). The material binding sperm were finally digested and disappeared in the bursa. The large material binding sperm is, therefore, a possible nutrient investiment from the male to the female in Cicadidae, Aphropholidae and Cicadellidae.