Red Rock Worm

Although Wijnhoven & Dekker (2010), followed by Hutchings et al. (2012), place Marphysa sanguinea (Montagu, 1813) as a new alien in the Netherlands, its type locality is nearby in the English Channel. Marphysa sanguinea, even if speculated that the English Channel is not its 'true' native habitat (no one yet appears to have proposed this, and Hutchings & Karageorgopoulos (2003:93) write that "... we suggest that the [neotype material] does not represent an introduced species"), has been present for at least two hundred years in the English Channel area, and conceivably for millions of years. Rather than a range extension to the Netherlands, or an alien arrival this species should be considered native there on present evidence, due proximity of locations. In a subsequent article Lavesque et al (2019) did not revisit whether Marphysa sanguinea could continue to be regarded as alien in the Netherlands, There appears to be no molecular data yet available confirming these records as the original Devon M. sanguinea, but morphologically they are that species, thus there is no reason to regard M. sanguinea as alien in the Netherlands [G Read, updated 08/07/2019].

Currently the distribution of Marphysa sanguinea is confirmed for the English Channel (on both coasts) to Netherlands, and south to Arcachon on the French coast. All other reports need verification and may be other Marphysa species.