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Comparative Cytogenetics. 2007. 1(2): 169-174.

On some terms used in the cytogenetics and reproductive biology of scale insects (Homoptera: Coccinea)

Gavrilov I.A., Kuznetsova V.G.

Abstract. The significance and validity of some terms conventionally used in papers on coccid cytogenetics and reproductive biology are discussed, and some suggestions are made for the terminology to be more correct in describing remarkable phenomena and processes associated with coccid reproduction and individual development. It is proposed to apply the terms “Lecanoid”, “Comstockiella” and “Diaspidid” referring to the genetic systems of scale insects not only to bisexually reproducing species, but also to parthenogenetic species and populations showing hetero-chromatinization of paternal set of chromosomes (PGH) during the development of male embryos. It is also proposed to unify the spelling of the above terms as follows: Lecanoid, Comstockioid and Diaspidoid. The classification of the known types of parthenogenesis of scale insects is revised, and the occurrence of facultative and obligatory parthenogeneses is discussed. The existence of true viviparous scale insects is questioned, and the term “ovoviviparity” (instead of “viviparity”) is treated to be the only proper one for all the hitherto studied species with embryonic development inside the mother’s body. The fusions of a cleavage nucleus with polar bodies resulting in the so-called “dizygotic soma” characteristic of the pseudococcid and diaspidid embryonic development is proposed to designate as the “Schrader fusions” in honor of Franz Schrader, the discoverer of this unique phenomenon.