Psammogammarus stocki n. sp. (Crustacea, Amphipoda, Melitidae) from beach interstitia on Tenerife. Stygofauna of the Canary Islands, 21

A description is given of Psammogammarus stocki n. sp. from the interstitial of loose sediments in heavily exposed rockpools in the mediolittoral zone of Tenerife, Canary Islands. The species apparently represents the ultimate apomorphous condition within the genus and co-occurs with Psammogammarus initialis Stock & Sánchez, 1987, a species that exhibits more primitive features.