Pityrogramma

Kessler, Michael, Smith, Alan R. & Prado, Jefferson, 2017, Prodromus of a fern flora for Bolivia. XXVII. Pteridaceae, Phytotaxa 332 (3), pp. 201-250 : 223

Key to the Bolivian species of Pityrogramma

1 Fronds, small, <15 cm long; blades deltate, <10 cm long; stipes <1 mm thick; blades lacking farina and hairs abaxially ............... ................................................................................................................................................................................... P. chaerophylla

- Fronds larger,> 25 cm long; blades narrowly deltate to oblong-deltate,> 20 cm long; stipes> 1 mm thick; blades usually with farina abaxially, if farina lacking then moderately hairy ............................................................................................................................ 2

2 Distal pinnae entire, linear or narrowly lanceolate .......................................................................................................... P. trifoliata

- Distal pinnae pinnately lobed or divided, narrowly triangular ......................................................................................................... 3

3 Blades abaxially hairy, lacking farina ............................................................................................................................. P. ochracea

- Blades abaxially without hairs, usually farinose .............................................................................................................................. 4

4 Rachises stramineous to pale reddish brown .............................................................................................................. P. chrysoconia

- Rachises lustrous brown to atropurpureous ...................................................................................................................................... 5

5 Basal pinnae equilateral, not elongated on the basiscopic sides; distal pinnae and pinnules ascending .......................................... 6

- Basal pinnae inequilateral, elongated on the basiscopic sides; distal pinnae and pinnules perpendicular to their axes .................. 7

6 Farina bright yellow to yellow-orange ............................................................................................................... P. austroamericana

- Farina white ............................................................................................................................................................... P. calomelanos

7 Farina white to pale yellow ................................................................................................................................................ P. ebenea

- Farina bright yellow to yellow-orange ........................................................................................................................... P. presliana