Hypolepis

Schwartsburd, Pedro B., Navarrete, Hugo, Smith, Alan R. & Kessler, Michael, 2017, Prodromus of a fern flora for Bolivia. XXVI. Dennstaedtiaceae, Phytotaxa 332 (3), pp. 251-268 : 256

Key to the Bolivian species and varieties of Hypolepis

1 Leaves intermittent (interrupted growth; blade apical growth pausing during pinna development) ............................................... 2

- Leaves determinate (regular and gradual development of pinnae and blade apices) ....................................................................... 3

2 Petioles and rachises armed with blackish spines; costae adaxially with decurrent wings ......................................... H. nigrescens

- Petioles and rachises unarmed; costae adaxially without decurrent wings ..................................................................... H. flexuosa

3 Petioles and rachises unarmed (axes may be rough due to bases of detached hairs) ....................................................................... 4

- Petioles and rachises armed with spines (may be scattered) ............................................................................................................ 7

4 Leaves eglandular ............................................................................................................................................................ H. obtusata

- Leaves glandular (glandular hairs present, at least on rachises and costae) ..................................................................................... 5

5 Veins and laminar tissue between the veins abaxially glabrous; pseudo-indusia absent .............................................. H. poeppigii

- Veins and laminar tissue between the veins abaxially with glandular hairs; pseudo-indusia present .............................................. 6

6 Leaves less than 25 cm long; pseudo-indusia copiously ciliate ....................................................................................... H. minima

- Leaves> 60 cm long (to 2 m); pseudo-indusia crenate to dentate, or with 1–3 cilia .......................................................... H. woodii

7 Abaxial laminar tissue between the veins glabrous .......................................................................................................................... 8

- Abaxial laminar tissue between the veins with hairs or trichomidia .............................................................................................. 10

8 Costae, costules, and veins abaxially with appressed trichomidia (each cell ca. 0.05 mm long or less) ......... H. parallelogramma

- Costae, costules, and veins abaxially with patent catenate or glandular hairs (each hair cell ca. 0.1 mm long) ............................. 9

9 Blades less than 1.5 m long; costules and veins abaxially with glandular hairs ............................................................... H. hostilis

- Blades more than 2 m long; costules and veins abaxially with catenate hairs ................................................................... H. repens

10 Costae, costules, veins, and laminar tissue between the veins abaxially with appressed trichomidia (each cell ca. 0.05 mm long or less) ................................................................................................................................................................................ H. scandens

- Costae, costules, veins, and laminar tissue between the veins abaxially with patent glandular hairs (each cell ca. 0.1 mm long) .... ......................................................................................................................................................................................................... 11

11 Petioles and rachises reddish brown; margins of pseudo-indusia ciliate ..................................................................... H. periculosa

- Petioles and rachises golden brown; margins of pseudo-indusia crenate to dentate (rarely with 1–2 cilia) .................................. 12

12 Leaves more than 1 m long (to 2.3 m); petioles and rachises densely spiny ......................................... H. rigescens var. rigescens

- Leaves less than 1 m long; petioles and rachises sparsely spiny ........................................................... H. rigescens var. buchtienii