CYRTOSPERMA TIMIKENSE
PROTOLOGUE:
Cyrtosperma timikense Imran & A.Hay, published in Aroideana 43(3–4): 97–107 (2020), "A third enormous New Guinea lasioid — Cyrtosperma timikense, a new species from southern Papua Province, Indonesia", with seven photographs.
Type: Imran s.n., 28 October 2020, Indonesia, Papua Province, Mimika Regency, near Timika, 4°39'47"S 136°49'36"E (holotype MAN; isotype BO, to be distributed).²
Diagnosis: resembles C. cuspidispathum in its very elongate spathe, gigantic size and small prickles, but differs in its strongly clumping habit, the somewhat angular distal part of the petiole and geniculum, the much narrower spathe with a somewhat inflated green basal portion, the stamens exserted from the tepals at male anthesis, the fruits apparently not expelled from the spadix at maturity, and the rather elaborately crested seeds, two to a berry.²
From the protologue: Massive, evergreen, strongly clump-forming herb to c. 3 m tall; stem a condensed subterranean rhizome 25–40 cm across including the leaf bases; leaves c. 8 per crown. Petioles held close together and vertical in the lower half and then weakly spreading, 2–2.5 m long, sheathing in the lower 30–40 cm with the wings of the sheath papery and then degrading to sparse fibres, dark grey-green densely and obliquely streaked buff in the lower half, bright green and somewhat angular in section above, sparsely armed with very small obliquely down-pointing prickles that follow the streaks below and become scattered and upturned above, conspicuously geniculate for c. 7 cm at the apex. Blades broadly triangular-sagittate, held with the anterior lobe up and the posterior lobes down, 1–1.5 m long, unarmed and rather small for the size of the plant; anterior lobe 40–50 cm long and 50–60 cm wide at the petiole insertion; posterior lobes 60–90 cm long; posterior costae diverging at c. 110° and naked in the sinus for c. 8 cm; anterior costa very prominent beneath, with about nine primary lateral veins on each side diverging at 60–70° and arching up to the margin, mostly with one or two secondary veins in the outer third of the blade; finer venation reticulate. Blooms solitary or up to three in succession; peduncles somewhat shorter than the petioles, 1.5–2.3 m long, densely armed throughout with small, mostly ungrouped, mostly upturned prickles like those of the petioles. Spathe to c. 80 cm long, somewhat convolute, green and slightly inflated in the basal 7–11 cm, giving the faint impression of a distinct lower spathe and limb, then narrowly canoe-shaped and very long-attenuate, dull purple with faint paler streaks within and slightly paler veins without, marcescent after anthesis and mostly disintegrated by fruiting. Spadix on a sparsely and minutely prickly stipe 2–3 cm long, tapering-cylindric, c. 20 cm long at female anthesis and enlarging to c. 26 cm during male anthesis; florets with six free tepals and six stamens, the anthers exserted from the tepals at male anthesis; pistil apparently unilocular and two-ovulate, the stigma discoid, sessile, almost as wide as the ovary. Infructescence at first erect, later deflected by pulvinar activity near the top of the peduncle, to c. 40 cm long; berries ripening red-orange, depressed-globose and weakly lobed with the darkened stigma remains at the top, apparently not expelled from the spadix, mostly two-seeded with one larger and one smaller (perhaps non-viable) seed; seeds reniform, ornamented with prominently lobed crests, c. 0.5 or c. 1 cm long.²
SYNONYMS:
HOMOTYPIC SYNONYMS: N/A
HETEROTYPIC SYNONYMS: N/A
ACCEPTED INFRASPECIFICS: N/A
DISTRIBUTION:
New Guinea: New Guinea (Papua Province, Mimika Regency).¹,²
DISTRIBUTION NOTE: Known only from the population near Timika from which the type was gathered, some 500 km west of the nearest southern record of C. cuspidispathum and on the far side of the Central Cordillera from the Jayapura records of that species.²
SPECIES DESCRIPTION:
A massive, evergreen, vigorously clump-forming herb to about 3 m tall, the base of a large clump forming a thicket of crowns, each of about eight leaves on a condensed underground rhizome 25–40 cm across. Petioles 2–2.5 m long, vertical and close together below and weakly spreading above, dark gray-green streaked buff in the lower half and bright green and somewhat angular above, sparsely armed with very small prickles and conspicuously geniculate at the apex; blades broadly triangular-sagittate, 1–1.5 m long, unarmed and rather small for the plant, held with the anterior lobe up and the posterior lobes down.²
INFLORESCENCE:
Blooms solitary or up to three in succession, on densely prickly peduncles 1.5–2.3 m long. Spathe to about 80 cm long, its green, slightly inflated, convolute base giving the faint impression of a distinct lower spathe, the rest narrowly canoe-shaped, dull purple, indistinctly streaked and drawn out into a very long, backward-arching tip. Spadix stipitate, tapering, 20–26 cm long; flowers hexamerous with the anthers exserted at male anthesis. Infructescence to c. 40 cm, deflected as it ripens; berries red-orange, depressed-globose, weakly lobed, apparently not expelled from the spadix, mostly two-seeded with one seed larger than the other; seeds reniform with prominently lobed crests.²
ECOLOGY:
Open degraded swamp forest at about 8 m altitude.²
DISTRIBUTION MAPS:
None seen.
ETYMOLOGY:
For Timika, the capital of the Mimika Regency in Indonesian Papua, near which the species was found.²
NOTES:
1. The third of the enormous New Guinea cyrtospermas, with C. cuspidispathum and C. giganteum, and the most like C. cuspidispathum in its size, its long-attenuate, basally convolute spathe and its very numerous small prickles. It differs in being vigorously clump-forming where C. cuspidispathum is usually solitary in the wild, in producing a few blooms in succession, in the much narrower spathe with only a small inflated green base (much more extensively convolute and vase-shaped, purple-brown, in C. cuspidispathum), reaching about 80 cm against 1.25 m, more indistinctly streaked and lacking the contrasting yellowish veins, in the exserted anthers, in the depressed-globose berries that stay on the spadix (rounder, and expelled anthurium-like, in C. cuspidispathum) and in the conspicuously crested seeds (barely ornamented in C. cuspidispathum).²
2. Discovered by Imran in the same part of southern Papua where the two authors had just re-found C. giganteum; the discovery is announced in a note added in proof to that paper, which puts the genus at fourteen species, eight of them on New Guinea.⁴
3. Described in the same issue of Aroideana as the rediscovery of C. giganteum and the note on C. johnstonii.²,⁴,⁵
4. Hariri et al. (2024) count it among the fourteen species known before C. prasinispathum.⁶
5. Seed is offered by at least one European seed merchant under this name, so the species is entering cultivation; no photograph has yet reached iNaturalist or GBIF, and the protologue's figures are the only published images.²,³ ⚠
STORY:
STORY TITLE: A close relative with diagnostic differences
Hay and Imran described Cyrtosperma timikense in 2020 as the third enormous New Guinea lasioid, after Cyrtosperma cuspidispathum and Cyrtosperma giganteum. It resembles Cyrtosperma cuspidispathum closely: the same scale, the same spathe, the same prickles, but the protologue lists diagnostic differences, including its exserted anthers at male anthesis.
There is no herbarium record of it in GBIF and no iNaturalist observation. Its seed, however, is sold commercially, so for most people the only way to meet this species will be to grow it.
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Cyrtosperma timikense.
2. Hay, A. & Imran. 2020. A third enormous New Guinea lasioid — Cyrtosperma timikense, a new species from southern Papua Province, Indonesia. Aroideana 43(3–4): 97–107 — protologue.
3. GBIF: no occurrence records (2026-09-05).
4. Hay, A. & Imran. 2020. Cyrtosperma giganteum Engl. (Araceae–Lasioideae) found again in Papua Province, Indonesia. Aroideana 43(3–4): 4–11.
5. Hay, A. 2020. Notes on the typification, origin, and fertility of Cyrtosperma johnstonii (Araceae–Lasioideae). Aroideana 43(3–4): 108–117.
Additional photos by anlileung | https://www.instagram.com/anlileung/
Additional photos by emflorescence | https://www.instagram.com/emflorescence/
Additional photos by lasplantas.id | https://www.instagram.com/lasplantas.id/