Iguanura mirabilis Lim (1998 a: 57)

Henderson, Andrew, 2025, A revision of Iguanura (Arecaceae, Arecoideae, Areceae), Phytotaxa 690 (2), pp. 135-188 : 167

19. Iguanura mirabilis Lim (1998 a: 57) . Type:— MALAYSIA. Terengganu, Ulu Setiu, 1993, Lim Chong Keat H 1448 (holotype KEP-169966!, KEP-169967!, KEP-21647!). Plate 2.

Stems 2.3(1.0–3.0) m long, 1.1(0.8–1.3) cm diameter, clustered. Leaf sheaths 10.3(9.0–13.0) cm long, tubular, mostly closed opposite the petiole, cleanly falling, covered with a thin layer of indumentum; ocreas well-developed, separating early into fibers and disintegrating; petioles 2.1(1.7–2.5) cm long; rachises 45.1(27.0–55.0) cm long; leaf blades undivided, not rounded at the apex, with a deep split; leaf veins parallel; adaxial leaf veins prominent, rectangular in cross-section; pinnae 1 per side of rachis. Inflorescences branched to 1 order; prophylls and peduncular bracts inserted some distance apart, more or less persistent; peduncles 9.7(9.5–10.0) cm long, not wooly tomentose; rachises 1.7(0.5–3.0) cm long; rachillae 4(3–5), 13.7(11.5–16.5) cm long, 2.3(1.8–3.0) mm diameter, widely diverging from the rachis, proximal part of rachillae not with distantly spaced triads, densely tomentose, not filiform with triads sunken in shallow, more or less closely spaced pits; rachilla bracts not elongate; distal triad bracteoles well-developed; distal part of flower pits densely tomentose or glabrous; staminate flowers 2.0– 2.5 mm long with blunt apices; anther margins not undulate; fruits 17.8(16.3–19.2) mm long, 5.3(4.7–5.9) mm diameter, narrowly ovoid, often curved, not ridged, the surfaces drying pebbled, white; endocarp circular in cross-section; endosperm homogeneous.

Distribution and habitat:—Northeastern Peninsular Malaysia in hill or lowland Dipterocarp forest, or swamp forest, at 81(41–120) m elevation (Fig. 12).

Taxonomic notes:— Preliminary species Iguanura mirabilis was polymorphic for one variable (pit tomentum). This was treated as a trait, and then preliminary species I. mirabilis had a unique combination of character states and is recognized as a phylogenetic species. It is characterized by its parallel leaf venation, raised veins, and curved, non-ridged fruits. It is notable for its short petioles and undivided leaves ( Plate 2).