Mkrtchyan, L.P., & Sarkisov, R.N. 2001 Some characteristics of the development of the sex organs in Margarodid males.. Entomologica 33(1999): 167-168.

Keywords:

  • anatomy
  • male
  • morphology
  • reproduction
  • reproductive system
  • Notes: [Special Issue: Proceedings of the ISSIS VIII International Symposium on Scale Insect Studies held at Wye College (U.K.), Aug. 31st - Sept. 6th, 1998.] Abstract only. A comparative study of the male sex organs of three subfamilies of the Margarodidae (namely Margarodinae, Monophlebinae and Coelostomidiinae) has shown that some morpho-functional rearrangements occur in their ontogenesis during the pre-imaginal period. These changes lead to a reduction of the testes and the formation of an evolutionarily new structure, a spermsac filled with semen bundles. During this general process of structural transformation, two types of spermsac construction can be distinguished, which allows the males of these subfamilies to be divided into two groups: 1. A group which has a spermsac with an ejaculatory duct which penetrates the more or less long, sclerotised penis (e.g., as in species of Porphyrophora, Steingelia and Matsucoccus) 2. A second group where the ejaculatory duct opens into the spermsac and the penis is very short and straight. In this group, the duct is turned out during copulation and then lowered into it - as in species of Icerya, Drosicha and Neomargarodes. The inner position of the ducts in the male sex organs of some scale insects (e.g., male Neomargarodes which retain rudiments of the testes) suggests that this is the primitive condition and that the external position of the ejaculatory duct is secondary. In addition, further study of the Margarodidae has shown that the duct has evolved differently in different groups. Thus, in the first group, the penis tube with the ejaculatory duct within it has developed progressively, while in the second group, in which the penis tube is short, the development of the ejaculatory duct seems to have occurred within the spermsac.