1. Leaf margins plane … 2.
1. Leaf margins recurved (revolute) … 4.
2. Upper laminal cells short, oval-rhomboidal, 1: 2 or less; seta stout; propagula present … D. pulvinata
2. Upper laminal cells oval, 1: 3 or more, ± porose; seta slender; propagula absent … 3.
3. Leaves oblong-ligulate, to 3.5 mm long … D. longifolia
3. Leaves lanceolate, 2.5-3mm long … D. brasiliensis
4. Leaves laxly imbricate; stems slender and elongate (to 4 cm long) … D. macrotheca
4. Leaves densely imbricate; stems shorter … 5.
5. Costa ending near midleaf or just beyond; upper cells linear or not … D. brevinervis
5. Costa longer, 3/4 or more lamina length; upper cells not linear … 6.
6. Leaves ovate; costa ± subpercurrent; median and upper laminal cells subquadrate to quadrate … D. jamesonii
6. Median and upper laminal cells linear to oblong or rhombic … 7.
7. Basal leaf cells linear, firm; border indistinct below … 8.
7. Basal leaf cells oblong; border distinct to insertion … 9.
8. Leaves lanceolate, 0.4-0.5 mm wide; propagula present … D. lindigiana
8. Leaves linear-lanceolate, 0.3 mm wide or less; propagula mostly absent … D. stenophylla
9. Plants robust; leaves 3-4mm long, border wide … 10.
9. Plants slender; leaves less than 3 mm long; border narrow … 13.
10. Seta smooth … 11.
10. Seta papillose (rough) above … 12.
11. Base margin forming a border of 10-15 rows of cells … D. bilimbata
11. Base margin forming a border of 7-9 rows … D. pellucida
12. Juxtacostal basal cells not differentiated … D. peruviana
12. Juxtacostal basal cells differentiated, cells long linear, similar to border (marginal) cells … D. latolimbata
13. Seta smooth … 14.
13. Seta papillose (rough)distally … 15.
14. Leaves linear-lanceolate; basal cells oblong-linear, delicate and hyaline … D. tenuifolia
14. Leaves oblong-ligulate; basal cells short oblong, firm and pellucid … D. trachyodonta
15. Leave linear-lanceolate, basal cells up to 50 µm long, oblong-linear … D. gracilis
15. Leaves lanceolate, basal cells 35 µm or less long, oblong … D. ovalis