ULTRASTRUCTURE OF THE TESTES AND SPERMATOGENESIS IN THE MITE
ANYSTIS BACCARUM
S. A. Filimonova
Zoological Institute, RAS, St. Petersburg, Russia;
The epithelial lining of testes in Anystis baccamm is glandular and produces a secretory product
necessary to form spermatophores. The main stages of spermatogenesis occur in the lumen of the testis in groups of synchronously
developing sister cells. Spermatogonia and late spermatids are encircled by glandular cells. Reorganization of developing
spermatids is typical of the trombidiform mites and includes formation of the acrosomal complex, cytoplasm elimination,
disappearance of the nuclear envelope and formation of imaginations of plasmalemma. The chromatin material condensation is not
followed by the entire chromatin body formation. In mature spermatoza, dense chromatin strands (80b nm in diameter) lie along
the cell in the peripheral layer of the cytoplasm. Mature spermatozoa lack axoncma or any protrusions. A layer of microtubules,
visible underneath the outer membrane, may serve for sperm movement in the female genital duct. The acrosomal complex consists
of acromal granule, acrosomal filament and subacrosomal substance. This, as well as two aggregates of typical mitochondria,
looks plesiomorphic.
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