The marine red alga known as Laurencia obtusa var. snackeyi (Weber–van Bosse) Yamada (Rhodomelaceae, Ceramiales) is characterized as follows: (1) production of 4 periaxial cells from each axial cell; (2) a few, percurrent, terete, thick main axes arising from a single discoid holdfast without stolon-like branches; (3) alternate-spiral branching; (4) presence of longitudinally oriented secondary pit-connections between contiguous superficial cortical cells; (5) absence of a palisade-like layer; (6) absence of projecting superficial cortical cells; (7) absence of lenticular thickenings in the walls of medullary cells; (8) parallel arrangement of tetrasporangia; and (9) presence of one corps en cerise per superficial cortical cell and trichoblast cell. It differs from L. obtusa (Hudson) Lamouroux in the absence of stolon-like branches with secondary attachment discs and the presence of thicker axes. The following binomial is proposed: Laurencia snackeyi (Weber–van Bosse) Masuda, stat. nov. Halogenated secondary metabolites of this species were investigated for samples from Vietnam and Malaysia. The major metabolites of the Vietnamese sample are palisadin A and aplysistatin, both sesquiterpenoids, whereas the Malaysian samples contain these compounds along with another monocyclofarnesol-derived sesquiterpenoid, 5-acetoxypalisadin B. L. snackeyi is also characterized by this set of secondary metabolites.