Iguanura beccarii Henderson, 2025

Henderson, Andrew, 2025, A revision of Iguanura (Arecaceae, Arecoideae, Areceae), Phytotaxa 690 (2), pp. 135-188 : 148

2. Iguanura beccarii Henderson , sp. nov. Type:— MALAYSIA. Sarawak, G. Berloban, 10 km, Tebakang/Tebedu Rd., 1 st Division, 90 m, 24 June 1983, Yii & Othman S.46221 (holotype SAR!, isotype L-0616422!). Plate 1 .

Stems 1.1(0.5–2.0) m long, 1.5(0.9–2.0) cm diameter, solitary or clustered. Leaf sheaths 11.3(8.5–15.5) 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 9.2(3.5–15.0) cm long; rachises 54.1(44.0–78.0) cm long; leaf blades divided, less often undivided, not rounded at the apex, with a deep split; leaf veins parallel; adaxial leaf veins prominent, rectangular in cross-section; pinnae 3(1–5) per side of rachis; middle pinna 30.8(26.0–41.0) cm long, 6.8(4.1–10.7) cm wide. Inflorescences spicate or branched to 1 order; prophylls and peduncular bracts inserted some distance apart, more or less persistent; peduncles 40.3(22.4–50.5) cm long, not wooly tomentose; rachises 0.7(0.0– 5.8) cm long; rachillae 1–3, 27.1(14.2–48.5) cm long, 2.6(1.6–3.3) mm diameter, widely diverging from the rachis, proximal part of rachillae with markedly distantly spaced triads, glabrous or sparsely to 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 4.0–5.0 mm long with pointed apices; anther margins undulate; fruits 10.7(8.7–13.0) mm long, 6.0(5.2–7.2) mm diameter, ellipsoid, ridged, the surfaces drying smooth, white, whitish-yellow, pinkish, red, reddish, red-orange, orange, or purplish; endocarp polygonal in cross-section; endosperm homogeneous.

Distribution and habitat:— Malaysia (western Sarawak) in mixed Dipterocarp forest or limestone forest at 106(20–300) m elevation ( Fig. 7 ).

Taxonomic notes:— Iguanura beccarii is recognized as a phylogenetic species—see notes under I. macrostachya . It is characterized by its long staminate flowers and smooth fruit surfaces.

Subspecific variation:—See notes under I. elegans .

Figures

PLATE 1. Isotype of Iguanura beccarii.

FIGURE 7. Distribution of Iguanura australis, I. beccarii, I. bicornis, and I. borneensis.