Macromitrium parvirete E. B. Bartram ex Grout 1944

Macromitrium parvirete E. Bartr. ; Grout, Bryologist 47: 16. 1944.
Plants densely cespitose, yellowish-green, not glossy; branches up to 2 cm. long, obtuse, densely foliate; leaves erect when dry, appressed-contorted, incurved at the apex, squarrosespreading when moist, about 2 mm. long, ligulate from an oblong-ovate base, obtuse, mucronate, the upper margins plane, minutely crenulate, the lower somewhat recurved; costa shortly excurrent; upper leaf-cells small, obscure, rounded, 6-8 i in diameter, not incrassate, strongly mammillose; basal cells linear, strongly tuberculate; perichaetial leaves small, ovate-lanceolate, acute, the costa percurrent; seta smooth, 6 mm. long; capsules short-urceolate, smooth, the urn about 1 mm. long; calyptra lacking hairs, deeply laciniate; operculum 1 mm. long, rostrate from a conical base; peristome simple, about 135 n high, the teeth attached one to another, irregularly divided above, papillose; spores papillose, 35 n in diameter.
Type locality: Costa Rica, between Rio Jesus and Calera de San Ram6n (Brenes 17075, type, in herb. Chicago Mus. Nat. Hist.; 17073, 17078).
Distribution: Costa Rica; Colinas de San Remo (Brenes 19077); Aguas Claras, Miravalles