Summary
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1.
The chromosomes of the African scale, Aspidoproctus maximus Louns., number 5 in the male, 6 in the female; sex chromosomes are of the XO male, XX female type.
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2.
Male meiosis is similar to that found in the Neotropical Llaveiini, with vesiculation of prophase nuclei, broadly dispersed polar centers, and divergent chromosomal fibers. The usual sequence of co-orientation and auto-orientation in meiosis is inverted; the chromosomes are autooriented at Metaphase I, and co-oriented at Metaphase II.
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3.
Asynapsis of one pair of autosomes occurs in from 14% to 52% (in different individuals) of the primary spermatocytes. Regular segregation of asynaptic chromosomes is ensured by a secondary pairing during interkinesis.
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4.
In spermiogenesis the chromosomes, linearly aligned, move out of the nucleus into the tail filament which forms a non-flagellated sperm.
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Hughes-Schrader, S. The chromosomes of the giant scale Aspidoproctus maximus louns. (Coccoidea-Margarodidae) with special reference to asynapsis and sperm formation. Chromosoma 7, 420–438 (1955). https://doi.org/10.1007/BF00329735
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DOI: https://doi.org/10.1007/BF00329735