Pitcairnia albifolia Cáceres González & A. Ibáñez, 2014

González, Daniel Adolfo Cáceres & Ibáñez, Alicia, 2014, Pitcairnia albifolia (Bromeliaceae), a new species from the Talamanca Mountains in Veraguas Province, Panama, Phytotaxa 172 (1), pp. 46-50 : 46-48

Pitcairnia albifolia Cáceres González & A. Ibáñez , sp. nov. ( Fig. 1–3 )

Type:— PANAMA. Veraguas Prov.: Distr. Santa Fe, Santa Fe National Park , La Sabaneta, premontane rain forest, elevation 1100 m, 08° 40’ 38.70” N, 80° 59’ 31.00” W, 15 July 2009, Fermín Hernández, José Guerra, Víctor Concepción & Alicia Ibáñez 5731 AI (holotype: PMA!; isotype: UCH!) .

This new species is similar to Pitcairnia nigra , but differs from it by its floral bracts that are shorter (4–6 mm long) and flowers pedicellate (up to 5 mm long), vs. floral bracts longer (65–80 mm long) and flowers sessile. The leaves in Pitcairnia albifolia are shorter (12.5–16.0 cm long × 3–4 cm wide) and adaxially densely covered with white lepidote trichomes; whereas the leaves in P. nigra are longer (60–67 cm long × 10–14 cm wide) and soon glabrous.

Plant terrestrial or saxicolous, acaulescent with a semi-erect short rhizome ca. 11 cm long and 3 cm diameter, covered by the densely imbricate old leaf-bases and roots, flowering ca. 52 cm high, normally individual plant with few leaves (5–7). Leaves semi-arching, homomorphic, persisting, petiolate, entire, stiff-chartaceous, 12.5–16.0 cm long, much shorter than the inflorescence; petiole 2.5–3.0 cm long, 0.5–1.5 cm wide, chartaceous, venation conspicuous, margins entire, white-lepidote on both sides; blades ovate-lanceolate to elliptic, 9–12 cm long × 3–4 cm wide (3–4 times longer than wide), long-acuminate, densely covered adaxially with white lepidote trichomes (sub-triangular, ca. 1 mm long × 0.5 mm wide) masking the green coloration of the blade, abaxially glabrous with some fine rigid points and a venation very conspicuous (15–20 veins per cm, the central vein not different), green. Peduncle elongate, not totally covered by its bracts, erect, slender, 31 cm long, 0.5 cm in diameter, internodes (1.5–4.5 cm long), white-lepidote. Peduncle bracts erect, longer than the internodes, chartaceous, 1.8–9.0 × 0.5–1.0 cm, triangular, distinctly nerved, margins entire, white lepidote in both surfaces, acuminate. Inflorescence (excluding the peduncle) 7.0 × 3.5 cm, erect, simple, with about 15 polystichous flowers, more or less open to compact, all bracts bearing flowers. Rachis for most part exposed between the flowers, reddish, straight, sparsely lepidote with minute white trichomes. Floral bracts triangular-ovate, divergent with the flowers, 0.4–0.6(–0.8) cm × 0.2–0.4(–0.5) cm, entire, apex acute, the lower ones equalling or exceeding the pedicels and the upper ones equalling or shorter than the pedicels. Flowers divergent at anthesis, diurnal, slightly zygomorphic. Pedicels up to 0.5 cm long. Sepals free, narrowly triangular, acute, 1.6–2.0 × 0.4–0.6 cm, with ca. 18 veins on the base (evident in dry specimens), slightly fleshy near the base, red-orange, slightly hyaline-margined, sparsely white lepidote to glabrescent. Petals free, asymmetric, erect to semi-recurving, 4.2–5.0 cm long, ca. 0.5 cm wide, nerved (ca. 15 veins in the widest part), acute, internally with one ligule at the base; more than twice as long as the sepals, glabrous, very dark purple; ligular appendage highly adnate (3/4) to the petal claw, 1.5 mm long × 0.5 mm wide, entire, subobtuse to slightly rounded (tongue-shaped). Stamens free, yellow, 4.0– 4.8 cm long; filaments all equal in length and conspicuously hyaline-margined when dry; anthers ca. 0.8 cm long, basifixed. Pistil (including the ovary) ca. 4.1–4.9 cm long, yellow, exceeding the stamens and nearly as long as the petals; ovary half superior, glabrescent, 4–6 mm long, about 3 mm in diameter; style slender, including the stigma 3.8–4.4 cm long; stigma trilobate, each lobe ca. 2 mm long and sub-globose, purple. Capsule up to 1.2 cm long, about 3 mm in diameter. Seeds not seen.

Etymology: —The specific epithet refers to the white color on the leaves (adaxially densely covered with white trichomes).

Distribution: — Pitcairnia albifolia is so far only known from the La Sabaneta on the Santa Fe National Park, Veraguas Province, in the Cordillera de Talamanca, Panama.

Habitat and Ecology: —The vegetation of this area resembles a highland savanna (ca. 1,000 m), an open formation dominated by the palm species Colpothrinax aphanopetala Evans (2001: 189 , Arecaceae ) and abundant grasses, sedges, shrubs, terrestrial orchids and bromeliads. The broader region falls within the realm of premontane rain forests, low and dense mixed formations where C. aphanopetala is the dominant element in the landscape. Also abundant are trees of the families Clusiaceae , Myrsinaceae , Ericaceae , Araliaceae , and others.

Phenology: —The few specimens found were observed flowering in July. Further investigations are required to determine exact flowering and fruiting seasons.

Conservation status: — Pitcairnia albifolia has been collected only once in Panama. Based on the herbarium collections studied and the botanical experience of the authors in the country, the La Sabaneta is a place with very special and unusual ecological characteristics. At this site, few individuals have been observed along the La Sabaneta and hence it is considered to be uncommon. Therefore, in the conservation assessment presented here (following the guidelines of the IUCN 2001), Pitcairnia albifolia is categorized as Critically Endangered (CR), represented by only one distribution record and based on the criteria B2bi–ii.

Discussion: —This new Pitcairnia resembles Pitcairnia nigra ( Carrierè 1881: 390) André (1888: 565) principally in the characteristic color of the petals (very dark purple), leaf and inflorescence type, but differs from it by its shorter floral bracts (4–6 mm) and pedicels up to 5 mm long vs. floral bracts longer (65–80 mm long) and sessile flowers. Pitcairnia albifolia has homomorphic leaves, up to 16 cm long × 3–4 cm wide, with entire petioles; while in P. nigra the leaves are trimorphic, 60–67 cm long × 10–14 cm wide, with stout serrate petioles. The specimen did not match any of the other known taxon in the genus.

Figures

FIGURE 1. Pitcairnia albifolia A. Saxicolous plant showing the leaves, densely covered adaxially with white trichomes (Photo A. Ibáñez). B. detail of the white trichomes on the upper side of the leaf blades (Photo Z. Serracín & D. A. Cáceres González).

FIGURE 2. Pitcairnia albifolia A. Terrestrial plant at the type locality, flowering in habitat (Photo F. Hernández). B. Inflorescence with very dark purple petals (Photo F. Hernández). C. Overview of La Sabaneta in Santa Fe National Park (Photo A. Ibáñez). D. Part of a dry leaf showing the veins on the abaxially side (Photo D. A. Cáceres González).

FIGURE 3. Geographical distribution of Pitcairnia albifolia. Map created by D. A. Cáceres González using ArcGIS Version 10.2.