Cyathea senilis (Klotzsch) Domin (1929a: 263)

Lehnert, Marcus, 2016, A synopsis of the exindusiate species of Cyathea (Cyatheaceae-Polypodiopsida) with bipinnate-pinnatifid or more complex fronds, with a revision of the C. lasiosora complex, Phytotaxa 243 (1), pp. 1-53 : 28-29

26. Cyathea senilis (Klotzsch) Domin (1929a: 263) . Alsophila senilis Klotzsch (1847: 442) . Sphaeropteris senilis (Klotzsch) Tryon (1970: 20) . Type:— VENEZUELA. Carabobo: Puerto Cabello, without date, H. Karsten 53 (lectotype B-20-0136904!, designated by Windisch 1978: 186, isolectotypes P-00642534!, PRC!).

Trunks 0.4–2.0 m tall, 4–6 cm diameter, covered with old petiole bases, due to these spiny; apices hidden between petiole bases; adventitious buds not reported. Fronds 170–240 cm long, presumably erect to arching. Petioles to 75 cm long, only proximally weakly aculeate with spines to 2 mm long, dark brown to blackish, rarely dark purpureous, matte to weakly shiny, basally with ephemeral scurf consisting of appressed reddish brown trichomidia and few erect, white, lanceolate to ovate squamules to 1 mm long with dentate margins and brown tips; hairs absent or restricted to adaxial side of distal petiole parts; petioles basally with a discontinuous line of distant lenticels (8–13 × 2 mm) on each side, grey-brown and inconsipious in dried material. Petiole scales long-lanceolate, to 35.0 × 1.5–2.0(–3.0) mm, relatively thin-textured, bases weakly cordate, basifix to pseudopeltately attached, straight to falcate, apices long attenuate, often strongly undulate; proximal scales concolorous, auburn to yellowish brown, distal ones often bicolorous with whitish margins; differentiated margins persistent, the cell rows not or only weakly exserted, with short teeth. Laminae to 125 × 60–100 cm, bipinnate-pinnatifid, firm-chartaceous to subcoriaceous, matte, dark green adaxially, often plumbeous when dried, dark olive-green abaxially, apices gradually reduced. Rhachises inermous, brown to purpureous abaxially and adaxially, adaxially pubescent with tan multicellular hairs to 1 mm long, antrorsely curved and persistent, abaxially glabrescent with few thin hairs and appressed trichomidia, leaving the epidermis smooth. Largest pinnae 30–50 cm long, pinnae subsessile or stalked to 1.0(–1.7) cm, ca. 10–12 pairs per frond, patent to weakly ascending, alternate, inarticulate, distally narrowly green-alate, distal segments simply adnate before ending in a pinnatifid apical section; basal pinna pairs not much smaller than the medial pinnae, weakly reflexed. Costae 1.5–2.0 mm wide, inermous, dark ochre to brown or orange brown abaxially, darker adaxially; with tan to brown, antrorsely curved multicellular hairs 0.5–1.0 mm long adaxially, glabrescent abaxially, with appressed reddish brown trichomidia and spreading white hairs 0.5–0.8(–1.0) mm long; junctures of costae and rhachises not swollen, abaxially often black when dried, each with an inconspicuous, planar to weakly protruding, elliptic aerophore to 2 × 1 mm. Largest pinnules 75–105 × (15–) 17–22 mm, sessile to subsessile, inarticulate, 1.3–2.0(–2.2) cm between the stalks/costules, lanceolate to oblanceolate, truncate to cuneate basally, long-acute to attenuate apically with serrate to crenulate margins; costules ochre or dark carnose to dark grayish brown adaxially and abaxially, proximally often darker; adaxially strongly prominent, ridged, and densely hairy with tan to brown, antrorsely curved multicellular hairs to 1 mm long, abaxially weakly to strongly prominent, densely and persistently hairy and scaly, the hairs erect, white, to 1.0(–1.2) mm long, the scales and squamules white to shiny brown with toothed margins and apical setae; bullate squamules 0.8–1.0 mm long, with matte white bodies and flat to caudate brown apices, and with flat lanceolate scales to 5.0 × 0.5–1.0(–2.0) mm, concolorous brown to white with brown margins; costules basally without pneumathodes. Largest segments 8.0–11.0 × 3.0–5.0 mm, sessile, adnate, never remote, patent to strongly ascending, distally falcate, tips obtuse to round, proximal segments alternate to subopposite, usually a bit shorter than following segments; sinuses acute, to 1.0(–2.0) mm wide; margins subentire to crenate; margins not differently incised in proximal segments of a pinnule; veins strongly protruding adaxially, planar to weakly protruding abaxailly, midveins ochre to yellowish, lateral veins yellowish green to green, ending before the margins, their ends adaxially widened and yellowish; veins abaxially with many erect, white to yellowish white, multicellular hairs to 0.8(–1.0) mm long on and between them, adaxially glabrous or with few hairs on an between them close to the costules; midveins with some pure white to light brown bullate squamules, to 1.0 × 0.5 mm; sterile and fertile veins simple or forked. Sori 1.0– 1.2 mm diameter, medial to supramedial, in the fork or on the back of veins, immature pale whitish yellow, mature dark orange-brown; indusia lacking; receptacles globose, 0.3–0.4 mm diameter, paraphyses numerous, rather stiff, straight or distally weakly bent, hyaline, whitish to tan, longer than the sporangia (0.6–0.8 mm long). Spores not examined.

Distribution and habitat: —Restricted to the Cordillera de la Costa in Venezuela, at (20–) 700–1500 m.

Selected specimens examined: — VENEZUELA. Aragua: Ricaurte, Cordillera de la Costa, Serranía del Interior , S of Las Tejerias and autopista Caracas-Maracay , range Los Novillos , 10º11’N, 67º11’W, 1400–1500 m, 8 February 2002, W. Meier & S. Nehlin 8981, 8966, 9005 ( UC!). Carabobo: Ca. 18–20 km S of Puerto Cabello , ca. 9–14 km S of San Esteban on old trail to Valencia, to ca. 4 km S of colonial bridge, 10º23’N, 68º04’W, 350–700 m, 15 April 1982, R. Liesner & V. Medina 13713 ( UC!) ; Bejuma / Montalban, Cordillera de la Costa , N slope, E of road Bejuma-Canoaba , E of Las Rosas , 10º16’N, 68º15’W, 950–1100 m, 26 December 2001, W. Meier 8769 ( UC!). Falcón: Cerro Santa Ana, going up the S slope from the village of Santa Ana, 800–850 m, 24 January 1966, J. A. Steyermark & A. Braun 94662 ( UC! US) . Miranda: El Volcán , SE of Caracas, 10º25’N, 66º51’W, 1300–1400 m, 31 December 1991, W. Meier 1148 ( UC!) ; Urdaneta, Cordillera de la Costa , Serranía del Interior , Macizo del Golfo Triste , rise between Quebrada La Providencia and ridge Las Yaguas , 10º03’N, 66º53’W, 1000–1100 m, 21 March 2004, W. Meier & S. Nehlin 10190, 10199, 10203, 10208, 10211 ( UC!) ; Urdaneta, Cordillera del Interior, Macozo del Golfo Triste , SW of Ocumare del Tuy, 10º03’30”N, 66º53’30”W, 1100–1300 m, 22 June 2001, W. Meier & S. Nehlin 8540, 8550, 8552 ( UC!) ; El Volcan, 10º25’30”N, 66º51’W, 1250–1400 m, 1999, W. Meier et al. 4855 ( UC!) ; Cerros del Bachiller, western sector, above Quebrada Bachiller, S of Caño Rico and Bachiller , 10º06–07’ N, 65º53’W, 20–690 m, 27–28 March 1978, J. A. Steyermark & G. Davidse 116571 ( UC!). Yaracuy: Along road between Salom ( E of Nirgua ) and Termaria, 6.3 km N of Salom , 10º18’N, 68º26’W, 930 m, 3 March 1993, T. B. Croat 74412 ( MO!, UC!) ; San Felipe, Cordillera de la Costa , Macizo de Nirgua , Montaña El Zapatero , SE of San Felipe and NW of Nirgua, between La Alegria and Terrón , 10º13’N, 68º37’W, 900–1000 m, 28 December 2003, W. Meier & Flauger 9687 ( UC!) ; Nirgua / San Felipe, Serranía Santa María , surroundings of Caserios Guayabalito and Orije , NW of Nirgua, 10º13’N, 68º30’W, 950–1150 m, 1 October 1999, W. Meier et al. 5258 ( UC!) .

Remarks: — Cyathea senilis is unique among Neotropical Cyathea due to its whitish bullate laminar squamules with dark brown, flattened tips that usually have dentate margins. Similar species with strongly hairy laminae and long paraphyses have concolorous laminar squamules. These are either pale ( C. lockwoodiana , C. parianensis , C. pilosissima , C. schlimii ) or dark ( C. calamitatis , C. lasiosora , C. pauciflora ), and if they are weakly bicolorous then they have attenuate to subulate tips (vs. flattened in C. senilis ). The species with dark laminar squamules ( C. calamitatis , C. lasiosora , C. pauciflora ) agree with C. senilis in having reddish petiole scurf on petioles that lack hairs, at least in their basal parts. Contrary to this, those species with pale laminar squamules have either hairy petioles that lack fine scurf ( C. parianensis , C. pilosissima ) or combine hairs and fine scurf ( C. lockwoodiana ).

The presence of dense reddish petiolar scurf in Cyathea senilis is similar to that of C. schlimii , but C. senilis can be easily separated by the rather stiff and straight paraphyses (vs. densely contorted in C. schlimii ). Cyathea senilis is similar to C. squamata (= Trichipteris microphylla ) in having dark petioles and leaf axes, pale brown petiole scales and the whitish squamules along the costae, but differs in having larger pinnules and longer paraphyses.

“ Alsophila senilis Klotzsch in Kunze“ (1846: 101) is an earlier nom. nud.