Hypolepis periculosa Schwartsb. 2017, sp. nov.
Creators: name: Schwartsburd, Pedro B.
name: Navarrete, Hugo
name: Smith, Alan R.
name: Kessler, Michael
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Polypodiopsida
Polypodiales
Dennstaedtiaceae
Hypolepis
Hypolepis periculosa

description: Hypolepis periculosa Schwartsb., sp. nov. (Fig. 1E–G)   
Spiny, reddish brown petioles and rachises, costae with long catenate-acicular and catenate-glandular hairs, laminar tissue between the veins abaxially with catenate-glandular hairs, and ciliate pseudo-indusia.  
 Type:— BOLIVIA. La Paz: Prov. Nor Yungas, a 5 km de Chuspipata hacia Coroico, 16°23’S, 67°48’W, 2700 m, 19 September 1997, M. Kessler 12087 with J. Gonzales, K. Bach & A. Portugal (holotype UC!; isotypes GOET!, LPB!).   
Plants terrestrial. Rhizomes 3–6 mm diam.; hairs catenate-acicular, reddish brown, 1–3 mm long, 10–30-celled. Leaves complete not seen, determinate, scandent, probably 2 m long or more; petioles complete not seen, ca. 5–7 mm diam., entirely reddish brown, glabrescent, rugose, the spines conspicuous, straight, 0.3–1.2 mm long; blades (complete not seen) tripinnate-pinnatifid to quadripinnate-pinnatifid proximally, at least 1.4 × 1.2 m; rachises straight, proximally reddish brown, stramineous above, spiny, rugose, glabrescent, with catenate-acicular and catenate-glandular hairs; basal pinnae ca. 60 × 22 cm, subequilateral; costae abaxially and adaxially pilose with two kinds of hairs, the first kind of hair catenate-acicular, hyaline with reddish cross-walls, 0.8–1.8 mm long, 8–18-celled, the second kind of hair catenate-glandular, hyaline with reddish cross-walls, 0.3–0.5 mm long, 4–6-celled; costules abaxially with catenate-glandular hairs, adaxially glabrescent; veins abaxially with catenate-glandular hairs, adaxially glabrescent; laminar tissue between the veins abaxially with catenate-glandular hairs, adaxially glabrous; laminar margins glabrous; sori marginal; pseudo-indusia proximally greenish, distally hyaline, the margins copiously ciliate.  
 Range:— Endemic to Bolivia (LP); known only from the type collection.   
 Ecology:— Rare; scandent terrestrial, in evergreen forests; 2700 m.   
 Etymology:— The epithet periculosa (Latin) means “dangerous”, an allusion to its densely spinulose petioles and rachises. In addition, it was collected along the infamous “death road” to Coroico, well known for its precipitous drops.   
 Notes:— Hypolepis periculosa is characterized by spiny, reddish brown petioles and rachises, costae with long catenate-acicular hairs (0.8–1.8 mm long, 8–18-celled) and catenate-glandular hairs, costules, veins, and laminar tissue between the veins (abaxially) with catenate-glandular hairs, and ciliate pseudo-indusia (Figs. 1E–G). It differs from H. rigescens by the reddish brown, stouter (5–7 mm diam.) petioles (vs. petioles proximally purplish or blackish, golden brown distally, 2.5–6 mm diam.), the copiously ciliate pseudo-indusia (vs. margins crenate to dentate, rarely with one or two cilia), and by occurring at much higher elevation. In addition, these two species differ slightly in their indument: the catenate-acicular and the catenate-glandular hairs of H. periculosa are longer.   
 The type of Hypolepis periculosa was previously identified as Hypolepis viscosa H.Karst. (Smith et al. 1999), but that species has inermous petioles and rachises, and pilose laminar margins, thus differing from H. periculosa. Hypolepis viscosa occurs in Colombia, Venezuela, and Hispaniola.
description: Published as part of Schwartsburd, Pedro B., Navarrete, Hugo, Smith, Alan R. & Kessler, Michael, 2017, Prodromus of a fern flora for Bolivia. XXVI. Dennstaedtiaceae, pp. 251-268 in Phytotaxa 332 (3) on pages 257-259, DOI: 10.11646/phytotaxa.332.3.2, http://zenodo.org/record/13723580