Phascum hyalinotrichum Cardot & Thériot, Bot. Gaz. 37: 363, plate 16, fig. 1. 1904

Seta 0.07-0.1 mm. Capsule cleistocarpous, immersed, ovate-apiculate, ca. 0.7 mm.

Capsules mature in spring. Soil, trailside, dirt road, Atriplex scrubland; low to moderate elevations (50-600 m); Calif.; Mexico (Baja California Sur, Zacatecas).

Stegonia hyalinotricha has the whitish leaves of Bryum argenteum and may be mistaken for that common weed, but the capsules are immersed and indehiscent. It was treated as Phascum hyalinotrichum by R. H. Zander (1994r). In this species, the abaxial walls of laminal cells are not differentially thickened.