During a taxonomic review of Sphagnaceae of Brazil, I found 5 collections in herbaria of Sphagnum squarrosum, an interesting species because of its typically robust form with strongly squarrose branch leaves that give this species a “spiky” look. These are the first records of this species from Brazil and the first of the subgenus Squarrosa from South America. These 5 records represent the southernmost known populations of this species in the Southern Hemisphere. A brief description, a key to the species of subgenus Squarrosa, and illustrations are given.