草间小黑蛛的核型

On Karyotype of the Erigonidium graminicola (Araneae Linyphiidae)

报道了草间小黑蛛的核型，包括染色体数目、形态结构和性染色体组成．材料采自石家庄市郊区．细胞学数据主要来自对混合胚胎细胞有丝分裂中期的观察．实验结果表明：草间小黑蛛细胞的染色体数是雄体细胞２ｎ＝２４，雌体细胞２ｎ＝２６，性别决定机制为Ｘ１Ｘ２Ｏ系统．Ｘ染色体为全部染色体中最小的和次最小的一个（对）．对其Ｃ－显带标本观察表明，所有染色体均为端或亚端着丝粒染色体，每个染色体都有其特点．

This Paper deals with the karyotype of the Hylyphantes graminicola . The chromosomal unmber,Chromosomal form and structure,and sex chromosome components of the species are reported.The experiment material were collected from the suburbs of shijiazhuang City. The cytological data were mainly obtained from mitosic metaphase of the embryo cells.The result shows the chromosomal number of H. graminicola is as follows:the somatic cell has 24 chromosomes in the male and 26 chromosomes in the female.It is considered that the machanism of sex determination is of the X 1X 2O type.Both(pairs) X Chromosomes are shortest and sub shortest.Analyse of its C band shows:all chromosomes seem to consist of telo or acro centries.Every chromosome has its own feature.