Trichostomum portoricense H.A.Crum & Steere

Stem rounded-pentagonal in section. Leaves flat but narrowly keeled along costa, long-ligulate, distal margins plane, entire (or tattered by fragmentation), not bordered; apex narrowly rounded, blunt, keeled; basal cells dif-ferentiated across leaf base, not running up margins, not distinctly enlarged submarginally; distal laminal cells with a massive multiplex papillae over each lumen; mucro short-conic, of ca. 3 cells. Sterile in range of the flora.