The standard karyotype of Oxycatantops spissus (Walker) (Orthoptera: Acrididae: Acridinae) from Limbe in the South West Province of Cameroon, comprises 2n = 23 acrocentric chromosomes in the male with the XO/XX sex determining mechanism [2n = 23 (22AA+XO)]. The karyotype structure is represented by five pairs of long (L1, L2, L3, L4, L5), three pairs of medium (M6, M7, M8) and three pairs of short (S9, S10, S11) autosomes. The acrocentric X chromosome is approximately equal in size to the short (S) autosomes. The meiotic process in this species was normal and chiasmate. Mean chiasma frequency in the wet season (16.36 ± 1.77) was significantly higher (p = 0.05) than in the dry season (15.00 ± 1.60). The differences probably lie in the fact that in the wet season many long bivalents had two or more chiasmata while in the dry season only a few long chromosomes had two or more chiasmata.

This article is a first record on the karyotypic features of Acrida turrita, Paracenema luculenta, and Morphacris fasciata (Orthoptera: Acrididae). The lacto-propionic orcein squash technique was used to prepare chromosome smears from the testes of specimens collected in May 2009 from the premises of the Institute for Rural Development (IRAD) Batoke, Limbe, in the South West Region of Cameroon. Analysis of these preparations revealed that the three species have the basic Acrididae complement consisting of 23 acrocentric chromosomes [2n♂= 23(22A+X0)]. The autosomes could be divided into 3 size groups: long, medium and short. The number of chromosomes in the different size groups varied among the species. A. turrita had 2 long, 7 medium and 2 short pairs of chromosomes while P. luculenta and M. fasciata each had 6 long, 2 medium and 3 short chromosome pairs. The mean chromosome lengths in the species were 71.80 ± 0.661µm, 83.70 ± 0.39µm, and 67.10 ± 0.31µm for A. turrita, P. luculenta and M. fasciata respectively. The X chromosome was medium in A. turrita and M. fasciata and long in P. luculenta. The chromosomes in these species were acro/telocentric in morphology.