Cyathea lellingeriana S.Maciel & J.Prado, 2017

Maciel, Sebastião, Lehnert, Marcus, Hirai, Regina Y. & Prado, Jefferson, 2017, Three new species of the Cyathea “ Hymenophyllopsis ” clade (Cyatheaceae) from Venezuela and Brazil, Phytotaxa 329 (2), pp. 159-166 : 163-165

Cyathea lellingeriana S.Maciel & J.Prado , sp. nov. Figs. 2A–D , 3 .

The new species Cyathea lellingeriana is similar to C. hymenophylloides by the presence of scattered clavate hairs on the rachises abaxially, which are absent adaxially, and the indusia valves being deeply lacerate on both sides. However, C. hymenophylloides differs in having ovate-lanceolate, concolorous rhizome scales and sterile segments with entire to subentire margins (vs. lanceolate to linear-lanceolate, bicolorous rhizome scales and sterile segments with crenate to erose margins in C. lellingeriana ).

Type:— VENEZUELA. Bolívar: Meseta del Jaua, Cerro Sarisariñama , Cumbre , porción Noreste , quebrada baja en selva más alta de promedio de 15–20 metros de alto, 04º41’40”N, 64º13’20”W, 1400 m, 16–18 February 1974, J. A. Steyermark , V. C. Espinoza & C. Brewer-Carías 109201 (holotype US barcode US 00785450!; isotypes NY barcode NY00144736 !, VEN, not seen) .

Plants rupicolous. Rhizomes slightly ascending or mainly erect, 1.2–2.4 mm in diam. (4.9–12.0 mm in diam. including roots, petioles and scales), with scales, surface of the rhizome usually visible between the scales, the scales lanceolate to linear-lanceolate, 1.2–2.7 × 0.20–0.35 mm, bicolorous, castaneous with diffuse darker brown central stripe, shiny, contorted toward the apex, bases round, the cells in the center with thick walls, margins light brown, entire, apices attenuate, castaneous. Fronds 3.3–18.0 × 0.9–3.8 cm, caespitose, erect; petioles 0.2–0.3 mm in diam., 0.7–8.0 cm long, brown to atropurpureous, terete, sparsely scaly at base, the scales like those of the rhizomes, but narrower and shiny, distally with scattered clavate hairs; laminae 5-pinnate, sometimes 6-pinnate at base, 3- or 4-pinnate distally, 8–30 pairs of lateral pinnae, lanceolate to linear-lanceolate, 2.6–10.0 × 0.9–3.8 cm, pinnae gradually reduced proximally and distally; rachises round on both sides or sometimes round abaxially and slightly flattened, not grooved adaxially, winged, the wing inconspicuous, up to 0.05 mm wide on each side of the rachis, glabrous adaxially and with scattered clavate hairs abaxially; pinnae 1.5–2.5 × 0.6–1.0 cm, triangular-lanceolate, mostly alternate, patent to ascending distally, near frond bases, subopposite to opposite, patent, 26–30 pairs per frond, 0.6–1.3 cm apart, approximate to imbricate, segments also covering the rachis, pinnae glabrous adaxially and with scattered clavate hairs abaxially, laminae highly dissected with relatively short overlapping ultimate segments; pinnules simple, pinnatisect to pinnate with distinct midvein (=costules), and to 4 pairs of lateral veins, these alternate, simple or forked up to 3-times, creating up to 15 terminal tips per segment; laminar tissue to 0.2 mm wide on each side of costae, up to 3 mm wide on each side of costules; ultimate segments with crenate to erose margins, round apices, sterile segments 0.4–0.7 mm wide, fertile segments 0.2–0.4 mm wide with one terminal sorus. Sori (10–)18–42 per pinnae, projecting or immersed in the laminar tissue, laminar tissue below indusia not constricted, sori occurring always on acroscopic and basiscopic base of the ultimate segments; indusia bivalvate, adaxial and abaxial valves ca. 0.5 mm long, margins fimbriate to deeply lacerate; spores 64 per sporangium, trilete, yellowish.

Distribution and Ecology: — Cyathea lellingeriana occurs in Venezuelan tepuis reaching as far as the Brazilian border. It grows on sandstone rocks, in crevices at the base of the rocks under forest canopy and under rock ledges. It is also common under wet rocks covered in mosses. It occurs between (770–) 1040–2450 m elevation.

Etymology: —This species is dedicated to Dr. David B. Lellinger (Curator Emeritus of ferns and lycophytes of the U.S. National Herbarium at the Smithsonian Institution) in recognition of his contributions to knowledge of the species of this peculiar group of ferns ( Lellinger 1984).

Additional specimens examined (paratypes): — VENEZUELA. Bolívar: Auyan-tepui, cumbre de la parte norte dela sección sur (división occidental del cerro), a lo largo del Río Churún al pie de “Second Wall” de arenisca, desde el campamento norte, 5 km hacia noroeste, [05º48’N, 62º28’W], 1660 m, 12 May 1964, J. A. Steyermark 93817 (US) ; Raul Leoni, bosque de altiplanicie en orilla de quebrada, parte N del Macizo Guanacoco , 04º57’N, 63º53’W, 770 m, November 1988, A. Fernandez & G. Aymard 4850, 4873 ( NY) ; Cerro la Danta, northwest of Cerro Venamo, wooded quebrada, northern slopes, headwaters of Río Venamo , west of vicinity of road campamento 125, [7º31’N, 64º29’W], 1040–1060 m, 13 April 1960, J. A. Steyermark & S. Nilsson 25, 33 ( NY) ; Cerro Guaiquinima, Río Paragua , [5°48’N, 63°44’W], 1600–1700 m, 31 December 1951, B. Maguire 32895 ( NY) .

Notes: — Cyathea lellingeriana can be distinguished from other species in having segments with crenate to erose margins. Additionally, the rhizome scales have round bases, cells of the scale center with thick walls, margins of the scale entire, and apices attenuate; rachises glabrous adaxially and with scattered clavate hairs abaxially, and pinnules with distinct costules.

Figures

FIGURE 2. A–D. Cyathea lellingeriana: A. Habit. B. Rhizome scale. C. Detail of the pinna. D. Detail of clavate hair on the rachises. E. Detail of the indusia (A Steyermark et al. 109201, NY; B–E Steyermark et al. 109201, US).

FIGURE 3. Distribution of Cyathea alsophiloides (stars), C. cylindrica (dot), and C. lellingeriana (triangle) in Venezuela and Brazil.