Distribution of the parasitic isopod Tachaea chinensis in China

Tachaea chinensis Thielemann, 1910 (Isopoda: Corallanidae) is a branchial ectoparasite that attaches onto shrimps and prawns. However, the distribution of T. chinensis in China, especially its epidemiology, remains unclear. We determined the prevalence of T. chinensis on the ridgetail white prawn (Exopalaemon carinicauda Holthuis, 1950) in Jiangsu Province. Fifty ponds in 10 shrimp farms were assessed. Isopod species were identified by morphological features and mitochondrial 16S rRNA gene analysis. A literature review was performed to determine the geographical distribution of T. chinensis in China. Published data revealed that T. chinensis was geographically distributed throughout five provinces in China, including Liaoning, Tianjin, Henan, Hubei, and Guangxi. A total of 998 T. chinensis were collected from 50 ridgetail white prawn ponds in Yancheng City and Rudong County. Tachaea chinensis prevalence ranged from 0.98% to 4.42% in Yancheng City and 0.62% to 0.92% in Rudong County. This is the first study to investigate the geographical distribution of T. chinensis in China and determine the prevalence of T. chinensis on the ridgetail white prawn in Jiangsu Province. Overall, we provide available data that fill gaps in the epidemiology of T. chinensis.