Abstract: To make clear the characteristics of karyotypes of long-horned beetles, supplement the chromosome classification feature and fill up the basic research vacancy of cytotaxonomy about long-horned beetles, the tissues with exuberant differentiation (testis, ovary and midgut) of four species of Lamiinae beetles were chosen for preparing slides of chromosomes under different conditions. The results showed that their chromosomal number is 2n=20 and the sex-determining mechanism is Xy_p. The karyotype of Batocera lineolata is composed of 4 pairs of large autosomes, 5 pairs of medium sized autosomes and 1 pair of small sex-chromosome, and the karyotype formula is 4L+5M+Xy_p. For Apriona germari, Olenecamptus cretaceus marginatus and Olenecamptus octopustulatus chinensis, their karyotypes are all composed of 5 pairs of large autosomes, 4 pairs of medium sized autosomes and 1 pair of medium sized sex-chromosome, and the karyotype formula is 5L+4M+Xy_p. The two long-horned beetles of Olenecamptus have very similar karyotype index. The chromosome size and the centromere location among A. germari, B. lineolata and Olenecamptus are obviously different.

Key words:  Long-horned beetles, chromosome, karyotype, sex-determining mechanism, centromere index