Cytology of neotropical phaneropteridae (Orthoptera-Tettigonioidae)

Abstract

The chromosome numbers of fifteen species of Brazilian tettigonids are reported in the present paper. Anaulacomera dimidiata, A. horti, A. sp. 1, A. sp. 2, Dysonia elegans, Diplophyllus acreanus, Phylophyllia guttulata and Topana aquillari all have 2 n (d) = 31 chromosomes, whereas 2 n (d) = 29 were found in Viadana longicercata, Phaneroptera quinquisignata, Phaneropterops piracicabensis and in the species 'numbered 583. In Posidippus eitrifolius specimens with 2 n (d) = 24 and 2 n (d) = 25 were found in two different populations. Prosagoga species show 2 n (d) = 17 and the species numbered 752 has males with 2 n=39. Within the super-family Tettigonioidea the family Phaneropteridae is characterized by a variation in its chromosome number that extends from 2 n (d) = 16 to 2 n (d) = 39. The chromosomal mechanisms involved in the karyotype evolution of the family Phaneropteridae are discussed.

Cytogenetics studies in thirteen Brazilian species of Phaneropterinae (Orthoptera: Tettigonioidea: Tettigoniidae): main evolutive trends based on their karyological traits

“…The karyotype 2n♂ = 31 was observed in 48 of 86 species studied and half of them show only acrocentric chromosomes with a NF = 31, collected in several localities around the world except in Australia, Japan (Ohmachi 1935), Brazil (Ferreira 1969(Ferreira , 1976(Ferreira , 1977Ferreira et al 1976), Canada (Beaudry 1973), Italia (Messina et al 1975 This kind of karyotype was considered by Ferreira (1977) as the ancestral for the majority of Phaneropterinae, and those different from the basic one derived by mean of different kind of rearrangements. The 2n♂=21 karyotype with all the chromosomes acrocentric, seems to be another branch of ancestry but not too recent since it was found in Australia and South America thought an independent origin can not be put aside.…”

“…infumata, A.chellata, A. linguata and P. verrucosa, belong to the second group, together with four species of the genus Caedicia (Ferreira 1977) and two of the genus Amblycorypha (Beaudry 1973) all of them with 2n♂ = 31 and NF = 32 due to a pericentric inversion of the X chromosome.…”

“…collected in Cruzeiro do Sul, Acre, Brazil, is 2n♂ = 19 with two submetacentric autosomal pairs surely originated by centric fusions involving medium and small autosomes from a karyotype similar to that of A. ferracioui (Ferreira 1977). Table 2.…”

“…The subfamily basic karyotype 2n♂ = 31 and NF = 31 (White 1973, Ferreira 1977) is prevalent in other eleven subfamilies of Tettigoniidae found all around the world. This karyotype, however, has not been observed in species of Mecopodinae, Heterodinae, Nedubinae and Gliphonotinae (Warchalowska-Śliwa 1998).…”

“…Within Phaneropterinae, six species are known to have neoXY♂ or X 1 X 2 Y♀ sex-determining mechanisms (Dave 1965;White et al 1967;Ferreira 1969Ferreira , 1977 involving X and autosomal chromosomes in species originally X0♂.…”