Hypolepis rigescens

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 : 259

Hypolepis rigescens (Kunze in Mart.) T.Moore var. rigescens, Index Fil. 11: 252. 1861.

Range:— Costa Rica, Panamá; Colombia and Venezuela southward to Bolivia (CO, LP, SC), northeastern, southeastern and southern Brazil.

Ecology:— Uncommon; erect terrestrial, in humid forests, especially in disturbed areas, along edges, and in secondary forests; 800–1900 m, 400–2000 m elsewhere.

Notes:— Hypolepis rigescens has commonly been confused with the similar H. hostilis . It differs from H. hostilis by petiole bases purplish or rarely black (vs. always black), golden-brown rachises (vs. stramineous), and laminar tissue between the veins abaxially with glandular hairs (vs. glabrous). Also, there are apparent elevational preferences: H. hostilis occurs at low elevations (200–500 m), H. rigescens occurs at mid-to high elevations (800–1900 m).

Hypolepis rigescens var. comb . & stat. nov. (Rosenst.) Schwartsb., stat. nov. for Hypolepis buchtienii Rosenst., Repert. Spec. Nov. Regni Veg. 25: 58. 1928. ( Fig. 2A–D )

Type:— BOLIVIA. La Paz: Casana in “valle Tipuani” [Tipuani-Tale], 1400 m, 29 September 1922, O. Buchtien 7014 (lectotype S-PA -n.v.,

designated by Tryon 1964: 38; isolectotypes UC!, US !).

Range:— Endemic to Bolivia (CO, LP).

Ecology:— Uncommon; erect terrestrial, in humid forests, especially in disturbed areas; 1400–1700 m.

Notes:— This local variety differs from the widespread Hypolepis rigescens var. rigescens by its smaller leaf sizes (30–100 × 20–50 cm vs. 100–230 × 50–80 cm), petioles and rachises sparsely spiny (vs. densely spiny), and petioles, rachises, and pinna rachises with conspicuous long reddish catenate-acicular hairs similar to those of the rhizomes (in addition to the hyaline catenate-acicular and catenate-glandular hairs) ( Figs. 2a–d ).

Figures

FIGURE 2. A–D. Hypolepis rigescens var. buchtienii (Buchtien 7014): A. Habit, B. Detail of petiole and rachis, abaxially, C. Pinnule, abaxially, D. Detail of veins, sori and pseuso-indusium, abaxially; E–H. Hypolepis minima (Jimenez 972): E. Habit, F. Detail of petiole, abaxially, G. Medial pinna, abaxially, H. Detail of veins, sori and pseuso-indusium, abaxially.