Corresponding author: Ashley Raymond Field (
Academic editor: A. Troia
Field AR (2018)
Herbarium materials of
A proposed Conservation status was assessed against the IUCN Red List Categories and Criteria (
Nouvelle-Hebrides: Erromango, forêt dense au N du camp du km 17, alt. 300 m, 4 Aug 1971,
Sporophytes herbaceous, epiphytic, with tufted isodichotomous arching to pendulous shoots and with dichotomous roots emerging from the base of the tuft. Shoots abruptly to gradually heterophyllous; sterile sections leafy, 12–18 mm in diameter and usually 20–50 cm long, evenly branched 1–4 times; fertile sections filiform-funiform, 2–4.5 mm in diameter and up to 300 mm long, branched 0–3 times, usually unbranched at base. Stems fleshy, 2.5–5.5 mm in diameter in basal module without the leaves, pale green or light stramineous brown, and bearing indistinct longitudinal grooves between the rows of leaves. Leaves sessile, supine, decurrent, firm, orthostichous in four strict rows comprised of 2 alternating sub whorls of 2, acutely spreading, ovate to ovate-oval, 6–14.5 mm long × 6–9 mm wide, with a broad rounded base and rounded, obtusely pointed or acutely pointed apex, leaves flat to twisted with entire margins, mid glossy green to light yellow green. Leaves in the basal modules more crowded, ovate with an acute apex and with a narrowed sub-petiolate base, in median modules more widely spaced and diverging, sessile with an almost amplexicaule base, and in the distal modules transitioning in shape to sporophylls. Sporophylls gradually to sharply differentiated from sterile leaves, sessile, supine, orthostichous in two alternating pairs of two, acutely divergent to adpressed, scale like, ovate-rhomboid with a cuneate to rounded amplexicaule base and an acute apex, 1.5–5.2 mm long × 1.5–2.8 mm wide, overlapping. Sporangia borne on the upper surface in the axils of sporangia, reniform, 1–1.2 mm in diameter, mostly covered by the sporophyll. Spores isotetrahedral, 30–40 μm in diameter, with convex lateral margins, smooth proximal surfaces and moderately foveolate distal surface. Gametophytes holomycoheterotrophic, dorsiventral with paraphyses among the gametangia on the upper surface.
VANUATU: Nouvelles Hebrides, [n.d.],
Endemic to Vanuatu where it occurs as an uncommon epiphyte on the bark of tree trunks and branches in the canopy to subcanopy of mature trees in lowland to montane primary tropical rainforest.
Vulnerable.
Named for the origin of this species in Vanuatu. Vanuatu is a composition of the Austronesian words ‘
The diagnostic traits of
Sporophytes herbaceous, epiphytic, with tufted isodichotomous pendulous shoots and with dichotomous roots emerging from the base of the tuft. Shoots abruptly heterophyllous; sterile sections leafy, 5–12 mm in diameter and usually 20–250 cm long, branched 1–6 times being relatively unbranched basally and more frequently ramified distally; fertile sections filiform, 1–2.2 mm in diameter and up to 400 mm long, multibranched 1–6 times. Stems slender and woody, 1.5–3.5 mm in diameter in basal module without the leaves, light green to dark purplish-brown, and bearing indistinct longitudinal grooves between the rows of leaves. Leaves sessile, supine, decurrent, firm, orthostichous in four strict rows comprised of 2 alternating sub whorls of 2, adpressed and imbricate, ovate-oval, 6–14 mm long × 4–7.5 mm wide, with a rounded base and similar rounded apex, leaves flat with entire margins, dark glossy green to light yellow green. Basal leaves sometimes more scale like and leaves in basal modules sometimes lanceolate-ovate and more widely spaced out on elongated naked stems, leaves in median and distal regions ovate-oval. Sporophylls markedly differentiated from sterile leaves, sessile, supine, orthostichous in two alternating pairs of two, scale like, adpressed throughout, ovate-rhomboid with a cuneate base and acute apex, 2.1–3.5 mm long × 1.4–2.2 mm wide, overlapping or occasionally spaced apart with stem visible between subwhorls of sporophylls. Sporangia borne on the upper surface in the axils of sporangia, reniform, 0.8–1 mm in diameter, mostly covered by the sporophyll. Spores isotetrahedral, 30–40 μm in diameter, with convex lateral margins, smooth proximal surfaces and moderately foveolate distal surface. Gametophytes holomycoheterotrophic, dorsiventral with paraphyses among the gametangia on the upper surface.
ASIA. VIETNAM. Tonkin: Saigon, [n.d.],
Widespread in Malesia and western Oceania where it occurs in New Guinea and the Solomon Islands as far east as the Santa Cruz Islands. A canopy and subcanopy epiphyte in lowland to montane tropical rainforest. This species often grows from decaying nests of other epiphytes, rotting logs and tree hollows but also will grow on bark on tree branches, especially where humus has accumulated.
Examination of G.H.Brownlie determinations on herbarium specimens indicates that reports of
The determination ‘
Recent combinations and descriptions of
This research was supported by (i) an Australian Biological Resource Study grant RFL215-34 (