Pleopeltis glandulosa Arana, Slanis & Bulacio 2024, sp. nov.
Creators: name: Arana, Marcelo D.
name: Slanis, Alberto
name: Bulacio, Eva
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Polypodiopsida
Polypodiales
Polypodiaceae
Pleopeltis
Pleopeltis glandulosa

description: Pleopeltis glandulosa Arana, Slanis & Bulacio, sp. nov.
Type:— ARGENTINA. Prov. Jujuy: Departamento Tilcara, Alfarcito, La Peña, en bajada al río, entre rocas, 2900 m a.s.l, 31 January 1971, O. Boelcke & J. Camara 80 (Holotype LIL [567011]!, isotype BAA [00008314]!). Figs. 1–2.
Diagnosis— Pleopeltis glandulosa is distinguished from the other species of Pleopeltis with abaxially fully covered by scales, by the glandular trichomes at the margins of the rhizomatic scales, alate stipes, the laminar scales with lateral, glandular papillae, and a long attenuate apex with a conspicuous glandular apical cell (versus non alate stipes, and scales without such glandular structures).
Plants epipetric or growing in rock crevices (Fig. 2 A); roots inserted ventrally; rhizomes slender, short-creeping (Fig. 1 A), 1.5–3 mm diam.; rhizome scales lanceolate to linear-lanceolate, peltate, appressed, imbricate, bicolorous, light brown with the central portion with a thick, blackish, indurate to sclerotic, lanceolate stripe, 1.5–2 × 0.5–0.8 mm, margins on either side of the stripe whitish to light tan, eroded in age, the margin fringed to denticulate (Fig. 2 D), with scattered glandular trichomes (Fig. 3 A). Phyllopodia short, indistinct. Fronds monomorphic, 4–15 cm long, clustered; petioles greenish to stramineous, alate, wings green (Fig. 1 B, 2 B), ca. 1/2 the frond length, grooved adaxially, moderately to densely scaly throughout, with lanceolate scales (1–1.5 mm long.), peltate, medium-brown, bicoloured with darker centres, clathrate, the apices long-attenuate, the margins strongly denticulate, teeth bipapillate; laminae ovate, subcoriaceous, dark brown in dried specimens, pinnatifid (Fig. 1 B, 2 B), up to 2 cm wide, the bases truncate, apices pinnatifid, segments ascending, 4–9 pairs, 2.5–3 mm wide, entire, border cartilaginous, apex obtuse, adaxial surface glabrous (Fig. 2 B); abaxial surface densely scaly (Fig. 1 C), with lanceolate, peltately attached, clathrate scales with dark brown centres, margins pale and denticulate, the teeth bicuspidate to bipapillate, glandular with mucilage (Fig. 3 C), apices filiform with a glandular apical cell (Fig. 1 D–E, Fig. 2 C, E, F) with mucilage (Fig. 3 B); veins free or rarely with one areole at the segment base, obscure by the thick lamina, without hydathodes. Sori in one row between the costa and the pinna margin, round to sightly oblong, 1–5 pairs per pinna, obscured by laminar scales when young, confluent at maturity on small pinnae; sporangia glabrous. Spores monolete, verrucate, light brown to yellowish, ellipsoidal to oblong in polar view and plane-convex in equatorial view, with the surface covered with irregularly distributed globular bodies (Fig. 3 D–E).
Distribution and habitat: — Pleopeltis glandulosa has a very restricted distribution area, growing in Jujuy and Salta provinces in Argentina, in the Prepuna district, which is the northernmost part of the Monte biogeographic province (Morrone 2017, 2018, Arana et al. 2021a), where it grows as epipetric or saxicolous, in rock crevices. The Prepuna district is characterised by xeric environments with deciduous thorny woodlands dominated by Zygophyllaceae, caesalpinioid Fabaceae, mainly Senna crassiramea (Benth.) H.S. Irwin & Barneby (1982: 569), plus the abundance of saxicolous Bromeliaceae as Deuterocohnia brevifolia (Griseb.) M.A. Spencer & L.B. Sm. (1992: 144), and columnar and creeping cacti, which sometimes become dominant (Fig. 4). The Prepuna extends north-south through Southern Bolivia and north-western Argentina, on the dry mountain slopes approx. between 2400 m and 3500 m a.s.l., where conform an ecotonal zone with shrublands and grasslands of Yungas affinities (Arana et al. 2021a).
Conservation status:— Because Pleopeltis glandulosa is known from just three localities, with an area of occurrence considerably smaller than 2000 km 2. Fieldwork suggests that most of its individuals are found in small and relatively isolated subpopulations, occupying very specific microhabitats. These data suggest a provisional inclusion of Pleopeltis glandulosa as Vulnerable (VU B1), according to IUCN Red List categories and criteria (IUCN Standards and Petitions Committee 2024).
Etymology: —The specific epithet refers to the glandular nature of trichomes at the margins of the rhizomatic scales, the glandular papillae at the margins of laminar scales, and the glandular cell at the apex of laminar scales.
Additional specimens examined (Paratypes):— ARGENTINA. Prov. Salta: Departamento San Carlos, Cuesta del Obispo, Valle Hermoso, entre rocas, fisuras, 20 September 1970, F. Vervoorst 7653 (LIL); Departamento Santa Victoria, Santa Victoria, acequia arriba, 2450 m, 14 February 1953, H Sleumer 4012 (LIL); Santa Victoria Oeste, 15 December 2021, E. Bulacio & A. Slanis 5283 (LIL).
description: Published as part of Arana, Marcelo D., Slanis, Alberto & Bulacio, Eva, 2024, Pleopeltis glandulosa (Polypodiales: Polypodiaceae), a new species from the Prepuna district of Monte biogeographic province in Argentina, pp. 181-188 in Phytotaxa 677 (2) on pages 182-185, DOI: 10.11646/phytotaxa.677.2.7, http://zenodo.org/record/14522222