First record of the Australian redclaw crayfish Cherax quadricarinatus (von Martens 1868) in Hong Kong, China

Abstract Invasive freshwater crayfish are spreading rapidly across the world. Here, we report the first record of Australian redclaw crayfish, Cherax quadricarinatus (von Martens 1868) in Hong Kong, China. Identification of the captured crayfish was confirmed using external morphological features and molecular analyses. A total of 49 crayfish were captured from a stream pool and a reservoir in Pok Fu Lam Country Park using dip nets and funnel traps. The captured C. quadricarinatus ranged from 17.20 mm to 56.40 mm (mean = 30.70) in carapace length and the sex ratio was 1:1. Since this species is globally recognized as an invasive species, a comprehensive survey on its status and invasion front, an investigation into its potential ecological impacts, as well as the formulation of a monitoring and removal strategy, are warranted.