Structure of ovaries of scale insects: II. Margarodidae (Insecta, Hemiptera, Coccinea)

The paired, spindle-shaped ovaries of the second instar of the Polish cochi neal, Porphyrophora polonica (L.) (Hemiptera: Coccinea) are filed with cyst ocytes that are arranged into rosettes. In the centre of each rosette, ther e is a polyfusome. During the third instar, cystocytes differentiate into o ocytes and trophocytes (nurse cells) and ovarioles are formed. Ovaries of a dult females are composed of about 300 ovarioles of the telotrophic type. E ach of them is subdivided into a tropharium (trophic chamber) and vitellari um. The tropharium consists of trophocytes and arrested oocytes that may de velop. The number of germ cells in the trophic chambers Varies from 11 to 1 8 even between the ovarioles of the same ovary. The obtained results seem t o confirm the concept of a monophyletic origin of the primitive scale insec ts (Archaeococcoidea). (C) 1998 Elsevier Science Ltd. All rights reserved.