Bartramia uncinata Schwagrichen, Sp. Musc. Frond. Suppl. 1(2): 60, plate 57 [bottom]. 1816; Philonotis glaucescens (Hornschuch) Brotherus

Plants small, in lax to dense tufts, yellowish. Stems 0.5-1.5(-3) cm, erect to inclined, simple, tomentose proximally. Leaves erect and straight or curved and homomallous when dry, erect-spreading when moist, triangular-lanceolate, 0.7-1.3 mm; margins plane proximally, narrowly revolute distally, bluntly serrulate nearly to base, teeth usually single proximally, paired distally; apex acuminate; costa percurrent to short-excurrent, distal abaxial surface rough; laminal cells , prorulose at distal ends, ; basal cells quadrate to rectangular, wider than distal, 10-65 × 8-12 µm; distal cells narrowly oblong, 20-50 × 5-8 µm. Specialized asexual reproduction by brood branches in distal leaf axils. Sexual condition dioicous; perigonia gemmiform. Seta 1.3-3 cm, straight. Capsule 1.5-2 mm. Spores subspheric to reniform, 23- 26 µm.

Capsules mature Feb-Mar. Rock, soil, open habitats; low elevations (0-30 m); Ala., Fla., Ga., Ky., La., Miss., S.C., Tex.; Mexico; West Indies; Central America; n, c South America; Pacific Islands.

Philonotis uncinata is restricted in the flora area largely to states bordering the Gulf of Mexico. The species is recognized by its diminutive habit, percurrent to short-excurrent costa, doubly toothed leaf margin and laminal cells prorulose at distal ends. Philonotis glaucescens, treated as a synonym here, has been recognized elsewhere as P. uncinata var. glaucescens (Hornschuch) Florschütz. The features by which P. glaucescens is recognized (whether as a variety or as a species) include straight leaves and a percurrent costa; these seem to fall within the variation displayed by P. uncinata, the oldest name available for this group of related forms.