Jamesonia (A. Tryon, 1962)

Kessler, Michael, Smith, Alan R. & Prado, Jefferson, 2017, Prodromus of a fern flora for Bolivia. XXVII. Pteridaceae, Phytotaxa 332 (3), pp. 201-250 : 221

Key to the Bolivian species of Jamesonia

1 Blade apices much narrower than the mid-blades, worm-like ................................................................................... J. scammanae

- Blade apices as broad as or broader than the mid-blades ................................................................................................................. 2

2 Rachis hairs dark reddish brown, only moderately dense even at the apices, <50% as long as the pinnae; pinnae in the plane of the blade ............................................................................................................................................................................. J. blepharum

- Rachis hairs yellowish to dark orange, dense at least at the apices,>50% as long as the pinnae; pinnae usually canted perpendicular to the plane of the blade .................................................................................................................................................................... 3

3 Inrolled blade apices 5–9 mm in diameter ....................................................................................................................................... 4

- Inrolled blade apices 2–4 mm in diameter ....................................................................................................................................... 5

4 Blades ± the same width throughout; all rachis hairs yellowish ....................................................................................... J. alstonii

- Blades continuously widening toward the apices; rachis hairs at apices chestnut, contrasting with the yellowish hairs lower down ........................................................................................................................................................................................... J. goudotii

5 Pinnae adaxially with long hairs, especially along the margins .................................................................................... J. peruviana

- Pinnae adaxially glabrous or with glandular hairs ........................................................................................................................... 6

6 Pinnae adaxially glabrous ............................................................................................................................................ J. brasiliensis

- Pinnae adaxially with glandular hairs ................................................................................................................................ J. scalaris