Cyathea neblinae A.R.Sm., 1990

Lehnert, Marcus, Tejedor, Adrian, Kessler, Michael, Rodríguez Duque, Wilson D. & Gallego, Luis Fernando Giraldo, 2025, A reassessment of the Neotropical Cyathea pungens complex (Cyatheaceae), European Journal of Taxonomy 988, pp. 1-57 : 19-20

Cyathea neblinae A.R.Sm.

Cyathea neblinae A.R.Sm. ( Smith 1990: 250) .

– Type: VENEZUELA • Prov. Amazonas, Dept. Río Negro, 0–1 km E of Cerro de la Neblina Base Camp on Rio Mawarinum ; 0°50′ N, 66°10′ W; 140 m a.s.l.; 2 Sep. 1984; R.L. Liesner & V.A. Funk 15781; holotype: UC [ UC1506573 ]!; isotype: MO [ MO-1873835 ] !.

Etymology

The specific epithet refers to the type locality.

Selected material studied

VENEZUELA – Amazonas, Dept. Río Negro • 0 to 1 km east of Cerro de La Neblina Base Camp on Río Mawarinuma ; 0º50′ N, 66º10′ W; 140 m a.s.l.; 9 Feb. 1984; R.L. Liesner 15798; MO, L, NY, UC, US. – Bolívar, Dept. Bolívar • Riberas del Río Canaracuni (aguas negras) y selvas adyacentes, Expedición Proyecto I.R.N.R.G. a la cuenca alta del Rio Caura (Hoja NB-20-14), convenio UNELLEZ-C.V.S. (TECHIN, C.A.); 4.450° N, 64.117° W; 13 Apr. 1988; B. Stergios 11892; MO, UC .

BRAZIL – Amazonas, Mun. Santa Isabel do Rio Negro • Neblina massif; 1300 m a.s.l.; 24 Dec. 2003 – 5 Jan. 2004; F.A. Carvalho et al. 308; INPA • same locality as for preceding; F.A. Carvalho et al. 320; INPA .

Description

Trunkless or trunks 0.3 m tall, decumbent, (1.0–)2.5–4.0 cm diam., with persistent old petiole bases, spiny; apices hidden between petioles; adventitious buds absent. Leaves to 90(–100) cm long, ca 3–5 in a crown; presumably arching. Petiole to 25 cm long with prickles 2–5 mm long, dark yellowish brown to dull orange-brown, sometimes basally darker brown; aerophores to 10 × 1 mm, inconspicuously brown in dried material, without remote (aphlebioid) pinnae at the petiole bases; petiole scales lanceolate, 8.0–9.0 × 2.5 mm, their tips straight to falcate, concordantly to discordantly bicolorous, shiny dark brown with whitish margins at petiole base, scales in distal half of the petiole gradually becoming paler with wider white margins, scales only sharply contrasted in scales near petiole base and on crosiers; petiole scurf a matted tomentum of small branched hairs and dissected squamules 0.2–0.4 mm long, yellowish white with brown parts, grayish white in general aspect, soon caduceus, persistent between prickles. Blades 58 × 46–50 cm, pinnate-pinnatifid to bipinnate-pinnatifid, elliptic to ovate-lanceolate, chartaceous; blackish adaxially when dried (probably dark olive-green when fresh), olive-green abaxially; apices gradually reduced. Rachises dark stramineous to orange-brown on both sides, in basal half often with some strong prickles; adaxially with antrorsely curved uniseriate hairs 0.5–1.0 mm long, abaxially glabrous except for scurf remnants, containing appressed, white trichomoidia and dissected squamules (0.2–0.5 mm). Largest pinnae to 23 cm long, pinnae (6–)8–12 pairs per leaf (in fully bipinnate-pinnatifid blades, may be higher in less divided ones), subsessile to stalked to 1 cm, ascending, narrowly green alate, the distal segments adnate, decurrent into the costae, forming a pinnatisect section with long acute to attenuate tips. Costae inermous, to 1.5–2.0 mm wide, adaxially with antrorsely curved uniseriate hairs 0.5–1.0 mm long, abaxially glabrous or glabrescent with scurf like on the rachises, insertions into rachises abaxially weakly swollen, each with an inconspicuous planar pneumathodes, dark brown, elliptic, to 2.0 × 1.0 mm, area around it often black in dried specimens. Pinnules 1.3–6.2 × (0.4–) 0.8–1.3 cm, smaller ones sessile, larger ones stalked 1.0 mm, articulate, alternate, ca 1.0– 1.5 cm between costules, linear-oblong to weakly elliptic, bases notably cuneate, tapering from beyond the middle, tips blunt in entire pinnules, long actue to attenuate to long acute to attenuate in pinnatifid pinnules, also caudate in pinnitisect pinnules; costules with ephemeral tan to brown trichomidia and whitish squamules 0.5–1.0 mm long with entire margins andacute tips; costules basally with a black ring going all around their bases (abscission layer); segments oblong, to 7.0 × 3.0 mm, strongly ascending, distally weakly falcate, with entire to subentire margins, tips obtuse to acute and then margins weakly dentate; basal segments alternate, sinuses in pinnatifid pinnules triangular, acute, 1.0–2.0 mm wide, in pinnatisect to partially pinnate pinnules the lowest segments remote from each other, separated by angular sinusus; veins prominent abaxially and adaxially, midveins strongly so and adaxially ridged, lateral veins ending at segment margins; midveins yellowish brown abaxially and adaxially, lateral veins yellowish to greenish brown or blackish; adaxially glabrous except for occasional single hairs on the midveins, abaxially glabrous or with squamules and trichomidia like on the costules; sterile and fertile veins mostly forked in bipinnate or less dissected blades, simple and forked in more strongly dissected blades and larger pinnules (> 1 cm wide). Sori 0.6–0.8 mm diam., supramedial, parallel to the margins, on the back of veins, indusia absent; receptacles globose to ellipsoid, 0.2 mm diam.; paraphyses few hyaline, white, shorter than sporangia (0.2–0.3 mm). Spores not examined.

See Smith (1990) for an illustration.

Distribution and ecology

Venezuela and Brazil, mainly around Cerro de la Neblina except for one outlying record from the southern base of Cerro Sarisariñama, mountain forests and scrub vegetation; at elevations of 100–1400 m a.s.l.

Remarks

This species was described as being only pinnate-pinnatifid to partially bipinnate; later records from Brazil (F.A. Caravalho et al. 320, INPA) have bipinnate-pinnatifid blades with stalked pinnules ( Carvalho et al. 2012), ultimately giving Cyathea neblinae the same variability in laminar disscection as C. pungens s. str.. Both species are also practically identical in petiole scale shape and color, laminar texture and color of the leaf axes, thus C. neblinae might be interpreted as a special dwarf form of C. pungens . However, there are some constant characters that make C. neblinae visibly different: the blade apex seems to be always gradually reduced (vs mostly subconform in C. pungens ); all plants described as C. neblinae ( Smith 1990) have pinnules with more strongly cuneate bases than C. pungens , irrespective of their size and degree of further dissection. In parts of the blade that mark the transition between simply pinnate and fully bipinnate, C. neblinae has remote adnate segments that are separated wide, assymmetric angular sinuses, formed by the decurrently alate bases at the basiscopic side of the segments. In direct comparison, such transitory sinuses are closer and more symmetric in C. pungens .