A new species Dactylospora mangrovei is described and illustrated and compared with D. haliotrepha and D. canariensis, all marine inhabiting species. Dactylospora haliotrepha and D. mangrovei are tropical/sub-tropical mangrove species collected in Hong Kong, Malaysia, Taiwan and Thailand, while D. canariensis was described from temperate waters. A map of the geographical distribution of the three marine Dactylospora species is presented.