Bryoria spiralifera Brodo & D. Hawksw and B. pseudocapillaris Brodo & D. Hawksw are two rare maritime lichens that were described from a small number of samples. This study describes the habitat and investigates chemical and morphological differences between the two species in the Picea sitchensis and Pinus contorta var. contorta forests of the Samoa Peninsula, location of the largest known population of B. spiralifera. Bryoria spiralifera is well distributed (100% frequency), and B. pseudocapillaris is less common (10% frequency) in each of the two stand types. Both species co-occur on the same branches, and both species are most abundant in high exposure sites such as forest edges along sand dunes and large canopy gaps. In Pinus contorta var. contorta stands, which tend to have open canopies, these two species are abundant, both in the understory as well as the upper canopy. In Picea sitchensis stands with more closed canopies, these species mostly occupy the upper canopy. Thin layer chromatography and logistic regression support the original hypothesis that B. spiralifera and B. pseudocapillaris are separate species. Thin layer chromatography showed that both species have distinctive, unshared secondary products. A logistic regression model finds several combinations of morphology as strong predictors of identity. Bryoria spiralifera is variable in regards to color and pseudocyphellae, but many have spiraling pseudocyphellae, while B. pseudocapillaris is mostly pale, with long, linear pseudocyphellae.