Phlegmariurus vanuatuensis A. R. Field

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 flat tassel-fern.

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.