Sex chromosome differentiation in Belostoma (Insecta: Heteroptera: Belostomatidae)

Abstract

ABSTRACT. Belostoma, a genus of the family Belostomatidae, includes species of great ecological importance as biocontrol agents. Few species of these species have been the subject of cytogenetic analyses. Karyotypic evolution in this genus involves agmatoploidy and simploidy; there are also different sex chromosome systems. We examined two Belostoma species (B. dilatatum and B. candidulum) collected from the Paranapanema River Basin (Brazil). Mitotic and meiotic analysis revealed 2n(♂) = 26 + X 1 X 2 X 3 Y for B. dilatatum and 2n(♂) = 14 + XY for B. candidulum; both karyotypes have holokinetic chromosomes. Differences in heterochromatin distribution were also observed between the species, besides variation in the localization of CMA 3 + /DAPI -blocks. The existence of different types of sex ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (3): 2476-2486 (2012) Sex chromosome differentiation in Belostoma 2477 chromosome systems in these species was confirmed based on arrangements of the chromosomes in different meiotic stages. We identified a new sex system in B. dilatatum, and make the first cytogenetic report on B. candidulum.

Karyotype diversity among predatory Reduviidae (Heteroptera)

“…In heteropteran species, many C-heterochromatic bands can be AT or GC-rich, such as in Montina confusa (Rebagliati et al 2003, Bressa et al 2005, Franco et al 2006, Bardella et al 2010, 2012, 2014a, Chirino et al 2013). In this way, the example of Triatoma infestans can be highlighted because the distinct repetitive DNA families (AT- and GC-rich) appear adjacently arranged at terminal chromosome regions (Bardella et al 2014b).…”

Sex chromosome pre-reduction in male meiosis of Lethocerus patruelis (Stål, 1854) (Heteroptera, Belostomatidae) with some notes on the distribution of the species

“…The adult bugs reach 80 mm in length. The information on the karyotypesof the genus Lethocerus has been recently summarized by Bardella et al (2012). In Lethocerus species, chromosome numbers vary from 2n = 4 to 2n = ca.…”

“…In several species, a pair of m-chromosomes (= microchromosomes) has been described (Ueshima 1979). As is common in Belostomatidae and in Heteroptera as a whole, all so far studied species of Lethocerus have been shown to have an inverted meiosis for the sex chromosomes in males (the so-called “sex chromosome post-reduction”) with the sex chromosomes undergoing equational separation during the first division while reductional segregation during the second division (Ueshima 1979, Papeschi and Bressa 2006, Bardella et al 2012). …”

Comparison of different cytogenetic methods and tissue suitability for the study of chromosomes in Cimex lectularius (Heteroptera, Cimicidae)

“…The spreading technique was also modified by Traut (1976) for male and female meiotic studies in lepidopteran species. Following his procedure, spreading was used successfully for chromosome studies of other heteropteran taxa, namely Corixidae: Micronectinae (Ituarte and Papeschi 2004), Reduviidae: Hammacerinae (Poggio et al 2011), Triatominae (Morielle-Souza and Azeredo-Oliveira 2007, Poggio et al 2013a), Reduviinae (Poggio et al 2013b), Coreidae (Bressa et al 2008), Pyrrhocoridae ), and Belostomatidae (Bardella et al 2012, Chirino et al 2013.…”