Calamus capillosus W.J.Baker & J.Dransf., 2017

Baker, William J. & Dransfield, John, 2017, More new rattans from New Guinea and the Solomon Islands (Calamus, Arecaceae), Phytotaxa 305 (2), pp. 61-86 : 63-65

2. Calamus capillosus W.J.Baker & J.Dransf. , sp. nov. Type:— INDONESIA. West Papua Province: surroundings of

Ayawasi, ca. 450 m, 1°09’S, 132°29’E, 28 July 1995, Ave 4048 (holotype L!, isotype BO).

Diagnosis:— Distinguished by the sheaths densely armed with very fine, hair-like spines, the regularly pinnate leaves with numerous bristles on veins and margins, the very long flagelliform inflorescences, the long, unbranched peduncle, the lax primary branches, and the staminate inflorescence branched to only two orders.

Slender, solitary rattan climbing to ca. 10 m. Stem with sheaths 12–15 mm diam., without sheaths 5–6 mm diam., exuding white sap when cut; internodes 14–17 cm. Leaf ecirrate to 65–90 cm long including petiole; sheath pale green, with thin, scattered indumentum of colourless and brown fibrous scales, densely armed with fine, hair-like, reddish-brown spines, spines to ca. 35 mm long, some indumentum scattered at base of spines, spines caducous later; knee 20–30 mm long, inconspicuous and obscured by spines; ocrea absent; flagellum to at least 1.9 m long; petiole 8–11 cm long, 5–5.5 mm wide and 4.5–5.5 mm thick at base, shallowly channelled adaxially, rounded abaxially, with indumentum as sheath, with caducous spines similar to sheath and grapnel spines abaxially; rachis 46–64 cm long, arching, with grapnel spines abaxially and laterally, and additional scattered, black-tipped spines; leaflets 48–53 each side of rachis, linear, longest leaflets at mid-leaf position, mid-leaf leaflets 16.5–18 × 0.9–1.1 cm, apical leaflets ca. 10 × 0.4–0.6 cm, apical leaflets not united, leaflets armed with numerous brown-black 1–3 mm bristles on margins and major veins of both surfaces, otherwise largely glabrous, transverse veinlets moderately conspicuous. Staminate inflorescence flagelliform, ca. 3.2 m long, flagelliform tip only weakly formed, branched to 2 orders; prophyll 27 × 0.4 cm, strictly tubular, splitting slightly at apex, indumentum and armature as petiole; peduncular bracts 3, peduncular and rachis bracts similar to prophyll; primary branches 7, to 42 cm long, 15–30 cm apart, lax, pendulous, flexuous, with up to 27 rachillae, bracts narrowly tubular, to ca. 15 × 1 mm; rachillae 30–55mm × 0.8–1 mm, recurving; rachilla bracts ca. 2 × 3 mm, distichous, shallowly cup-shaped, with scattered brown scales; floral bracteole ca. 2.3 × 3 mm, cup-shape. Staminate flowers 2–2.3 × ca. 1.3 mm in bud; calyx ca. 1.5 mm diam., tubular in basal 0.5 mm, with 3 lobes ca. 0.6 × 1.2 mm, with scattered brown scales; corolla 2.3–2.5 × 1.2–1.3 mm in bud, tubular in basal ca. 0.5 mm, with scattered brown scales; stamens 6, filaments 1.1–1.2 × 0.1–0.2 mm, anthers 1.4–1.6 × 0.4–0.5 mm; pistillode 0.7–0.8 × 0.2–0.3 mm, trifid. Pistillate inflorescence not seen. Pistillate flowers not seen. Sterile staminate flowers not seen. Fruit not seen. Seed not seen.

Etymology:— The species epithet refers to the very hairy appearance of the leaf sheaths, due to the abundance of fine, hair-like spines, and the numerous hair-like bristles on the leaflets.

Distribution:— Known only from the type locality near Ayawasi in the Bird’s Head Peninsula.

Habitat:— Disturbed forest at ca. 450 m.

Uses:— None recorded.

Vernacular names:— None recorded.

Specimens examined:— INDONESIA. West Papua Province: surroundings of Ayawasi, ca. 450 m, 1°09’S, 132°29’E, 28 July 1995, Ave 4048 (holotype L!, isotype BO).

Notes:— Among the non-ocreate, flagellate Calamus species in New Guinea, Calamus capillosus is likely to be confused only with C. schlechterianus Beccari (1913: 119) , on account of its sheaths densely armed with very fine, hair-like spines and regularly pinnate leaves with linear leaflets. The species is much more slender than C. schlechterianus and is entirely different in reproductive form, producing very long flagelliform inflorescences with a long peduncle, and primary branches that are elongate, lax and branched only to two orders in the staminate material seen by us. Calamus schlechterianus , in contrast, has much more robust, non-flagelliform inflorescences, with relatively compact and highly branched primary branching systems. There is also a superficial similarity to the Australian C. australis Martius (1838: 213) , which also has sheaths densely armed with fine spines and regularly pinnate leaves. Nevertheless, while only a single staminate specimen was available to us, we are in no doubt that it represents a species that is new to science.