Record of Parasesarma lenzii (De Man, 1895) (Decapoda, Brachyura, Sesarmidae) from the Cocos-Keeling Islands, with a redescription and designation of a lectotype

The mangrove crab Parasesarma lenzii (De Man, 1895) s. str. is herewith recorded from the Cocos-Keeling Islands in the Australian Indian Ocean Territories. The species was originally described based on seven specimens from Aceh and Penang, six of which seem to be lost; and we here designate the extant syntype as the lectotype. A brief redescription of the species is provided, and in addition, a segment of the DNA sequence corresponding to the mitochondrial gene and barcoding region COI, was amplified from two individuals and submitted to GenBank for comparative purposes. Aspects of the taxonomy of this species are discussed.