Meiotic Behavior of Chromosomes in Two Species of Coreinae (Coreidae: Heteroptera)

Coreinae, the largest subfamily of Coreidae, is distributed worldwide hut is most abundant in the tropics. Its 2 tribes, Homoeocerini and Petascelini, are specifically found in the Eastern Hemisphere. In 118 species of Coreinae cytogenetically analysed so far, male diploid number ranges from 15 to 29 and variations are reported in chiasma frequency, metaphase arrangement pattern and anaphasic movement of sex chromosomes during meiosis. In view of this, meiotic behavior of chromosomes in 2 North Indian species of Coreinae viz. Hotnoeocerus signatus Walker (Homoeocerini) and Petillopsis patulicollis (Walker) (Petascelini) has been described for the first time and characteristic features are discussed in the present paper. The male diploid chromosome complement of H. signatus Walker is 2n=21=18A+2m+X0 while that of P. patulicollis (Walker) is 2n=28=24A+2m+X(1)X(2)0. The general course of meiosis is fairly uniform and is typical for heteropteran types. During diplotene, a single chiasma per bivalent is observed in H. signatus Walker whereas 2 chiasmata are observed in 2 to 3 bivalents in P. patulicollis (Walker). In both the species, the arrangement of chromosomes at metaphase I is typical of coreid types. In P. patulicollis (Walker), however, a few metaphase I plates are observed with an alternate arrangement.