Longbract Pohlia Moss (Pohlia longibracteata)

Description

Dioicous with male plants similar to female. Perigonia terminal, bud-like with perigonial leaves larger than vegetative leaves and forming splash-cups. Perichaetial leaves longer and relatively more narrow than vegetative leaves, strongly spreading from the base. Seta pale brown to red-brown, smooth, erect, to 20 mm long. Urn red-brown, to 2 mm long, oblong, 2-3: 1, strongly inclined to pendent, with a poorly defined neck, neither sulcate nor strumose. Operculum conic rostrate to short rostrate. Exothecial cells at capsule mouth not differentiated from median exothecial cells. Exothecial cells at middle of urn isodiametric with rounded lumens and with strongly bulging trigones, to 28 -m broad, in regular rows. Stomates cryptoporous, restricted to neck and immediate base of capsule, not conspicuously raised on pustules, nearly isodiametric. Annulus fragmenting at dehiscence, inconspicuous, of 1-2 rows of relatively thick-walled cells. Exostome pale to yellow-brown, to 450 -m long, inconspicuously shouldered, very inconspicuously horizontally striate at base but strongly papillose distally, dorsal lamellae low. Endostome about as long as exostome, with basal membrane constituting about 1/2 of total length. Segments weakly papillose, keeled and broadly perforated along center line. Cilia 1-3, mostly nodose. Calyptra cucullate and smooth, mostly shed before capsule maturity. Spores to 15 -m, finely papillose to almost smooth.Pohlia longibracteata is a moss of eroded creek banks and of loose soil of flood plains. It can readily be identified by the erect and unbranched habit; the reddish stems and leaf bases; the very elongate leaves with hand-lens-visible cells. The splash-cup perigonia of the male plants are usually very obvious. When a stem cross-section is viewed under the compound microscope, the pentagonal nature of that cross-section is accentuated by the sharply winged nature of the angles of that pentagon. The species epithet may be somewhat misleading in that all the leaves are, for the genus, unusually long with the perichaetial leaves not as conspicuously longer as the name may imply.