Two new semi-cryptic species from the marine littoral zone of NW Europe, Hydropunctaria oceanica and H. orae, are described. Both differ from H. maura in their ITS and mtSSU sequences and in their thinner thalli and H. orae also differs in its green rather than brown cortical pigment. Hydropunctaria aractina comb. nov. is reinstated as an accepted species, but is difficult to distinguish from H. orae by morphology alone. Lectotypes and epitypes are proposed for H. aractina and H. maura.