Ultrahistology of oogenesis and vitellogenesis in the spider mite Tetranychus urticae

Egg-Shells in mites: Cytological aspects of vitelline envelope and chorion formation inPergamasus barbarusberlese (Gamasida, Pergamasidae)

“…As far as the latter process is concerned, the Acari have only occasionally been investigated. Several studies have dealt with ticks (Diehl, 1970;Hecker and Aeschlimann, 1970;Brinton and Oliver, 1971;Diehl, et al, 1982) and spider mites (Tetranychidae) (Dittrich and Streibert, 1969;Mothes and Seitz, 1981;Mothes-Wagner, 1984; Mothes-Wagner and Seitz, 1984), but egg-shell formation in most of these publications has been only briefly mentioned. Similarly, the information on the fine structure of egg shell in mites has been presented only in a few cases: gamasid mites (Witalinski, 1977), ticks (Diehl, et al, 1981), and acarid mites (Mazzini and Baiocchi, 1983;Callaini and Mazzini, 1984).…”

Vitellogenesis in Varroa jacobsoni, a parasite of honey bees

“…To solve this problem, more experimental work is required. The few studies reported for other acari cover only a limited number of species (Diehl, 1970;Brinton and Oliver, 1971;Alberti, 1974;Witte, 1975;Weyda, 1980;Diehl et al, 1982;Mothes-Wagner and Seitz, 1984;Coons et al, 1986;Witalifisky, 1993). Other open questions include the formation of the egg shell and the cells contributing to this activity.…”

Post-embryonic development of the two-spotted spider miteTetranychus urticaewith special reference to the differentiation of the female reproductive system

“…The large nuclei exhibit conspicuous, often ring-shaped nucleoli. Nurse cells may be interconnected via cytoplasmic bridges [15]. Directly beneath the protruding oocytes, some cells of type 2d can be observed situated at the periphery of the ovary (Fig.…”

“…The development of male [12] and female germ cells of T. urticae [13][14][15][16][17] has been of special interest. The female reproductive system consists of an unpaired ovary where according to the accumulation of defined oogenesis stages a cranial germ region, a middle previtellogenic region, and a caudal vitellogenic region are distinguishable [10,13,15,18,19]. During ovarian development, different cell types are observed: oogonia, growing oocytes, nurse cells and chromatin-rich cells [10,[13][14][15][16][17].…”

“…The female reproductive system consists of an unpaired ovary where according to the accumulation of defined oogenesis stages a cranial germ region, a middle previtellogenic region, and a caudal vitellogenic region are distinguishable [10,13,15,18,19]. During ovarian development, different cell types are observed: oogonia, growing oocytes, nurse cells and chromatin-rich cells [10,[13][14][15][16][17]. Oogonia and primary oocytes are observed already in larvae, growing oocytes in deutochrysalises, and the oocyte/nurse cell complex in deutonymphs.…”