Nepenthes zygon

Synonymy

Nepenthes zygon Jebb & Cheek in Blumea 59: 151, fig. 3. 2014 sec. Cheek & Jebb 2014

Type: Cheek 17059 (holotype K; isotypes L, PNH), Philip- pines, Mindanao Island, Mt Pasian, seed collected in 1997 by R. Cantley, cultivated at Royal Botanic Gardens, Kew as accession 2004-2413, male infl. Sept. 2013.

– "Nepenthes alata" sensu Danser 1928: 261, quoad Elmer 142482, non Blanco, p.p., err. sec. Cheek & Jebb 20141
– "Nepenthes alata var. ecristata" sensu Macfarlane 19273, non Macfarl., p.p., err. sec. Cheek & Jebb 20141: 137, quoad Elmer 14248

1. Cheek, M. R. & Jebb, M. H. P. 2014: Expansion of the Nepenthes alata group Nepenthaceae), Philippines, and descriptions of three new species. – Blumea 59: 144-154, 2. Danser, B. H. 1928: The Nepenthaceae of the Netherlands Indies. – Bull. Jard. Bot. Buitenzorg, sér. 3, 9: 249-438, 3. Macfarlane, J. M. 1927: The Philippine species of Nepenthes. – Philippine Journal of Science 33

Content

Description

Terrestrial climber 2–3 m tall, possibly sometimes rooting on bases of stunted trees in cloud forest. Stem terete, 5.5–9.5 mm diam. Rosette and short stems not well-developed. Climbing stems with internodes (2.8–)5–12 cm long, axillary buds filiform 5(–7) by 0.9 mm long, inserted 6–9 mm above the axil, indumentum of patent brown ‘dagger hairs’ (Kurata 2003) 0.2 – 0.5(– 0.8) mm long, very sparse to 20 – 30 % surface coverage, denser in leaf axils; sessile red depressed-globose glands 0.05 mm diam, scattered throughout. Leaves thinly coriaceous, petiolate. Rosette leaves oblanceolate, 14–18 by 4–4.5 cm. Leaves of climbing stems narrowly oblong-elliptic, 21–24(–30) by 2.8–5.5(–7) cm; apex acute, not peltate; base decurrent to petiole; longitudinal nerves 1–2 pairs, 2–10 mm from the margin, arising from the midrib of the blade, conspicuous above; pennate nerves numerous, patent, conspicuous above; midrib upper surface 20–30 % covered in a mixture of dark brown simple or ‘dagger hairs’ 0.06–1 mm long and white, (2–)3–6-armed bushy to substellate hairs 0.2–0.25 mm diam, margin densely shortly hairy with same hairs, blade otherwise mainly lacking hairs except thinly scattered white hairs; sessile, red depressed-globose glands 0.05 mm diam scattered throughout; lower surface with midrib 10–20 % covered in dark brown ‘dagger hairs’ 0.5–0.6 mm long, mixed with substellate pale brown bushy hairs arising from a dark red base, 4–6-armed, 0.15–0.2 mm diam, extending very sparsely to the blade (i.e. Elmer 14248) or moderately densely c. 3 hairs mm2; margin densely ciliate with hairs as in upper surface of midrib. Petiole winged, broadly U- or V-shaped in section, (6–)7–10 by 0.6–1(–2) cm. Lower pitchers (tendril not coiled) ellipsoid-cylindric, 9–14 by 2.5–5 cm, widest in the ellipsoid lower half, upper half cylindric 1.5–2.5 cm wide; fringed wings present from base to peristome, wings 3–4 mm wide, fringe elements 4–5 mm long, (2–)3–5.5 mm apart; outer surface 30–50 % covered in minute (3–)4-armed stellate hairs 0.1 mm diam, mixed with sparser (c. 5 % cover) hairs 0.75–1.3 mm long superficially simple but bearing 1–2 short side branches from the central axis. Mouth ovate-elliptic, 2.5–4 by 1.7–2 cm, oblique, not, or only weakly concave, column not present; peristome cylindric 2–4 mm diam, even in width throughout, ribs 0.5–0.6 mm apart, raised 0.4 mm, in life the inner edge appears to be without teeth or holes, which can be found on dissection, outer edge not lobed. Lid orbicular-elliptic, 2–2.5 by 1.8–2.9 cm, apex rounded, base slightly cordate; basal ridge and appendage absent in the smaller pitchers (c. 10 cm tall), resembling those of the upper pitchers in the larger (c. 15 cm tall) pitchers; nectar glands and indumentum resembling those of upper pitchers but sparser. Spur triangular c. 2.5 by 1.5 mm, tapering from base to rounded apex; densely covered in brown bushy and ‘dagger hairs’ 0.3–1 mm long. Upper pitchers (tendril coiled) ellipsoid-cylindric (9–)16–25 by (2.6–)4–5.5 cm, widest in the basal ellipsoid, 7–8 cm long portion, above cylindric narrowed to (1.8–)2.5–3(–3.5) cm diam; indumentum as lower pitchers, colour when live with basal, swollen part of pitcher green (drying brown), overlain with white waxy layer, cylindrical part with faint to well-marked longitudinal red-purple stripes and flecks, inner pitcher surface waxy green (drying pale purple), spotted with purple; fringed wings present only immediately below the peristome (0.6 –)1.7– 3.5 cm long, widest at the peristome where (1–)2.5–7.5 mm wide, fringed elements 3–6 mm long, 1.5–3 mm apart, the uppermost longest and raised above the peristome; mouth ovate, 3.5 – 5 by 2.5 – 3.3 cm, oblique, slightly concave, column weakly developed; peristome subcylindric (flattened only before the pitcher is fully opened Fig. 3b) (1.5–)2–3(–5) mm broad, ribs 0.3 mm apart, about 0.01 mm high, outer margin entire, revolute, inner margin without conspicuous teeth, revolute (edge with holes visible only when dissected, (Fig 3q), green or red and green in colour; lid ovate (2.2 –)3.3 – 4.5(– 4.9) by 2.5 – 4(– 4.6) cm, apex rounded or slightly retuse, base cordate, the sinus 1–1.5 cm wide, 5 mm deep, lower surface with a basal ridge 1.5 cm long, rising gradually to 0.5–1 mm high, tapering to the extremities, and bearing in the centre a convex or recurved-hooked appendage (Fig. 3n) projecting 3–4 mm from the lid surface, 4–7 mm long; nectar glands are of two types and mostly confined to two approximately lanceolate areas, which are joined at the basal ridge, nectar glands being largely absent from a marginal band 5–8 mm wide and from the distal half of the midline; they are thinly scattered on the basal appendage; type 1: nectar glands (90 % of the total c. 1 per mm2) are small, thinly bordered, orbicular or elliptic, 0.1–0.2 mm in length; type 2: nectar glands are similar in appearance, but much sparser and larger 0.5–0.6(–0.7) mm long; sessile red-black depressed-globose glands 0.05 mm diam, c. 3 per mm2 are scattered over the whole of the lower surface; marginal 2–3 mm 50 % covered in stalked bushy brown hairs 0.1–0.2 mm diam, several occurring towards the centre of the lid, 8–10 mm from the edge; spur simple, filiform, 5–9 mm long, 0.5 mm wide, apex obtuse, densely covered in appressed hairs 0.5–1 mm long. Male inflorescence c. 47 by 3.5 cm, indumentum moderately dense, covering 40–50 % of the surface, hairs pale brown, a mixture of ‘dagger hairs’ 0.5–1 mm long, and 2–4-armed bushy hairs 0.2–0.25 mm long; peduncle c. 27 by 0.3 cm; rhachis c. 20 cm long, with partial-peduncles 75–80, 2-flowered (1-flowered at apex); bracts recurved or patent, filamentous, c. 3 mm long, acute, inserted along the length of the partial-peduncles; partial-peduncles 4–6 mm long; pedicels c. 15 mm long, indumentum covering 30–50 % of the surface, hairs bushy, 1–3-armed, erect, 0.2–0.5 mm long; tepals 4, elliptic, 6 by 4 mm, outer surface 50–60 % covered in a mixture of simple, acute hairs 0.15–0.25 mm long, and sessile mucilaginous papillae 0.005 mm diam, inner surface densely covered in elliptic nectar glands; staminal column 5 mm long, moderately densely hairy along its length, hairs 0.1 mm long, more or less patent, red-brown, simple or with a basal branch; anther-head subglobose, 2.5 mm diam. Female inflorescences, infrutescences and seed unknown. A

Conservation

N. zygon is here assessed as Critically Endangered under IUCN (2012), criterion D based on less than 50 individuals (in fact two) being known from the wild with certainty. A

Distribution (General)

Philippines, NE Mindanao, Mts Masay and PasianA

Habitat

Submontane mossy forest along ridges, thought to be non-ultramaﬁc, 1500 –1875 m a.s.l.A

Bibliography

A. Cheek, M. R. & Jebb, M. H. P. 2014: Expansion of the Nepenthes alata group Nepenthaceae), Philippines, and descriptions of three new species. – Blumea 59: 144-154

Specimens

	Country	Date	Collector + collecting number	Herbaria	Type	Scan	Derivatives
	Cheek 17059 (holotype K; isotypes L, PNH), Philip- pines, Mindanao Island, Mt Pasian, seed collected in 1997 by R. Cantley, cultivated at Royal Botanic Gardens, Kew as accession 2004-2413, male infl. Sept. 2013.
	Citation: Cheek 17059 (holotype K; isotypes L, PNH), Philip- pines, Mindanao Island, Mt Pasian, seed collected in 1997 by R. Cantley, cultivated at Royal Botanic Gardens, Kew as accession 2004-2413, male infl. Sept. 2013.