Ultraestructure of the vitellogenic process in the king crab, Chaceon affinis

Abstract

Early (previtellogenic) oocytes of deepwater crab Chaceon affinis show a high nucleus-cytoplasm ratio, a single nucleolus, and the nuclear envelope shows abundant nuclear pores. Small "nuages" are seen at the perinuclear cytoplasm. The cytoplasm contains ribosome-like particles, round mitochondria, and electron-clear vesicles. During vitellogenesis cytoplasmatic membrane inclusion proliferate. The cytoplasm also has multivesicular bodies and vesicles enclosing a dense granular core surrounded by an electron-clear matrix.