Cytotaxonomic Studies On Some Species Of Caryanda (Orthoptera Acridoidea)

Cytotaxonomy is an important part of synthetic taxonomy develops classical taxonomy and provides a new method for further systematics because it puts knowledge of cytology to use in taxonomy. Relations between biological groups which is revealed by cytotaxonomy can be regarded as collateral information for classical taxonomy, and it provides a cytological evidence for classical morphological taxionomy oras a craze of modern systematics----systematically evolutionarybiology.The present paper has first made chromosome C-banding reseaches on 9 grasshopper species of Caryanda and 1 species of Pedopodisma which are collected from Hunan Province and Chongqing. Squashed preparations were made and C-banding was carried out by the BSG method described in Webb (1978). Parameter determine has been made in the light of experimental results of chromosome C-bandings. Then the data determined were inputted into Excel system to process. Sketch maps of C-karyotype of the 10 species have been designed to scale by data from the tables and distributuins of C-bands from micro-photographs. The paper first has made a comparative reseach on frequency of chromosome chiasma and the length and width of testes follicles of 8 grasshopper species of Caryanda. Considering both of Pedopodisma and Sinopodisma,are closer to Caryanda in morphology, so the comparative analyses has been made by the data of chromosome in order to define the relation among Pedopodisma, Sinopodisma and Caryanda. In view of characters of C-banding karyotypes 31 variables are selected to define the relations among 9 grasshopper species and thatamong 3 grasshopper genera by software of SPSS system. The main points of results are as follows.1. The karyotype and Obanding in the 9 species of CaryandaThe chromosome basic numbers of grasshopper species of genus Caryanda remain 2n( <2)=23. Pattern of sex determination is XO (<2) or XX(ï¿¡). Karyotype formulae, except C. wulingshand s, are mainly 3L+6M+2S+X or 2L+7M+2S+X, namely 3 pairs of large chromosomes, 6~7 pairs of medial chromosomes and 2 pairs of small ones. X chromosomes, except Caryanda sp2(from the Jinfoshan Mountains), are all small ones.The 9 species of genus Caryandahave all showed acrocentric C-bands. The 8 species of the genus, except C. xuefengshana, have showed abundant C-bands, especially C. hunari s no. 1> 2^ 4> 6 and 7 chromosomes (see appendix 1). In addition, Caryanda obtusidentata (from the Mangshan Mountains ) has showed heterozygous C-bands in no. 3 chromosome. The 9 species of genus Caryanda have different contents of heterochromatin with each other: C. hunari sis the most (36. 05%), and Caryanda triodonta s is the least (13.38%).2. The frequencies of chiasmaThe frequencies of chiasma are all higher in the 9 species (7.8), and Caryanda triodonta' s is the highest (9. 47).3. The relationgships among Caryanda, Pedopodisma and SinopodismaIn the paper, the suitable variables have been selected to make a comparison among the 3 genera and structure a systematic tree by software of SPSS system. From cladistic drawing given by software of SPSS system, it comes to conclude that genus Pedopodisma is closer to Sinopodisma than Caryanda .4. The relationships among 9 species of genus Caryanda by...