Iguanura leucocarpa Blume (1838: 66)

Henderson, Andrew, 2025, A revision of Iguanura (Arecaceae, Arecoideae, Areceae), Phytotaxa 690 (2), pp. 135-188 : 161-163

13. Iguanura leucocarpa Blume (1838: 66) . Lectotype (here designated):— INDONESIA. Sumatra, no date, Collector and collection number not recorded (lectotype L-0042121!).

Stems length not recorded, 0.6 cm diameter, branching not recorded. Leaf sheaths 9.8(9.6–10.0) 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 10.7(9.2–12.2) cm long; rachises 28.7(27.8–30.0) cm long; leaf blades divided, not rounded at the apex, with a deep split; leaf veins diverging; adaxial leaf veins not prominent, triangular in cross-section; pinnae 4 per side of rachis; middle pinna 17.7(17.0–18.4) cm long, 5.3(5.0–5.9) cm wide. Inflorescences spicate; prophylls and peduncular bracts inserted some distance apart, more or less persistent; peduncles 9.5 cm long, not wooly tomentose; rachises 0 cm long; rachillae 1, 8.5 cm long, 1.7 mm diameter, proximal part 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; staminate flowers 4.0–5.0 mm long with pointed apices; anther margins not recorded; fruits not recorded.

Distribution and habitat:— Sumatra, habitat and elevation not recorded. No distribution map is given because of the uncertain locality of the few specimens, as discussed below.

Taxonomic notes:— Preliminary species Iguanura leucocarpa had a unique combination of character states and is recognized as a phylogenetic species. It is characterized by its adaxial leaf veins not prominent, triangular in cross-section, and long staminate flowers with pointed apices.

Kiew (1976) indicated that the type of Iguanura leucocarpa was at BO, but according to Dr. Himmah Rustiami it is not there. The lectotype at L comprises a single, fertile sheet, annotated as lectotype by Harold Moore in 1956. The label says Sumatra without any other information except for an indecipherable, abbreviated name that is possibly that of Praetorius. Kiew (1976), for unknown reasons, considered that the type was collected by Korthals in Padang. There are two other specimens at L determined as I. leucocarpa . One (L-1407303) is sterile and the label states only ‘ Pinanga’; the other (L-1407404) is supposedly from Sumatra with a packet with staminate flowers. None of the three L specimens has the collector unambiguously written on the label, although Blume (1843) implied they were collected in Sumatra, by Praetorius in Palembang and Korthals in Padang. Palembang and Padang are more than 500 km apart, implying that Iguanura leucocarpa has a wide distribution. However, no more recent specimens have been seen from Sumatra, despite the areas around Palembang and Padang being relatively well collected.

PLATE 5 . Holotype of Iguanura grandis .

Kiew (1976) described the anthers as lobed, but this does not appear to be the case, based on Blume (1843, tab. 117). Kiew described the fruits as: “Fruits (from illustrations in Rumphia) olive-shaped, not ridged nor ribbed”. However, no fruits were illustrated by Blume (1843, tab. 117), nor are they present on any specimen. One specimen with fruits, at FI from a cultivated plant from Bogor, and determined by Harold Moore as I. leucocarpa , appears to be I. geonomiformis .