ISSN:
1432-0886
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary 1. Chromosome behavior at spermatogenesis has been described for one species each of three families of coccids not previously studied in this regard: Cerococcus quercus Comstock of the Asterolecaniidae, Conchaspis lepagei Hempel of the Conchaspidae, and Tachardiella sp. of the Lacciferidae. All three families belong to Balachowsky's “lecanoid” section of the coccid superfamily, and the first two have been suggested, by various systematists, as close allies of the armored scales (Diaspididae). 2. All three species showed lecanoid chromosome behavior, as originally described by the Sohraders, in that one haploid set of chromosomes is heterochromatic in the males and eliminated at spermatogenesis. The exceedingly clear cytology of C. quercus permitted a detailed study of the critical second division stages when the euchromatic and heterochromatic sets are separated. Although considerably more difficult cytologically, both the other species showed a typical lecanoid pattern of behavior; in addition, both showed an accessory structure, of unknown origin and function, which was present during the meiotic sequence. 3. The cytological and taxonomic implications of the results are considered, largely on a comparative basis, in the discussion. Special attention is given to the problem of the origin of the armored scales and also to Buchner's recent suggestion of the possible influence of symbionts on sex determination.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00396575
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