Abstract: The transcriptome sequencing data of the red claw crayfish （Cherax quadricarinatus） was analyzed, and the primers were developed by PCR amplification and capillary electrophoresis, the primer polymorphism and versatility analysis were carried out. 22,727 simple repeat （SSR） sites were detected from 67,369 Unigenes, and functional annotations were performed on Unigenes containing SSR sequences. The results show that, the microsatellite sequences in the transcriptome of the red claw crayfish are abundant, and the dinucleotide and trinucleotide repeat types appear more frequently, accounting for 52.67% and 44.25% of the total SSR frequency, respectively; the tetranucleotide pentanucleotide and hexanucleotide repeat types appeared less frequently, accounting for 2.62%、 0.23% and 0.24% of the total SSR frequency, respectively. There are 68 SSR repeat types, and the number of repetitions ranges from 5 to 84.5 pairs of SSR primers were screened, and 60 samples from Zhejiang and Taiwan were analyzed for genetic diversity, the average polymorphic fragment per every prime was 5.6. The results of this study lay the foundation for the in-depth development of functional SSR markers of red claw crayfish, and also support the molecular marker-assisted breeding of red claw crayfish.

Key words: Cherax quadricarinatus, transcriptome, SSR, information of loci