CYRTOSPERMA GRESSITTIORUM
PROTOLOGUE:
Cyrtosperma gressittiorum A.Hay, published in Blumea 33: 439 (1988), as "gressittorum", with Fig. 4.
Type: L.J. Brass 28049, Papua New Guinea, Milne Bay Province, Sudest (Tagula) Island, Rambuso, 11 September 1956 (holotype L; isotype A). Hay's diagnosis: differs from all other species of Cyrtosperma in the hooded spathe.²
SYNONYMS:
HOMOTYPIC SYNONYMS: N/A
HETEROTYPIC SYNONYMS: N/A
ACCEPTED INFRASPECIFICS: N/A
DISTRIBUTION:
New Guinea: New Guinea (Sudest Island).¹
DISTRIBUTION NOTE: Known only from the type gathering on Sudest (Tagula) Island in the Louisiade Archipelago, in rainforest on the crest of a ridge at 150 m.²
SPECIES DESCRIPTION:
Herb to 70 cm tall. Petiole to 60 cm long, the sheath papery and c. 15 cm long, the spines sparse, straight, needle-like, to 3 mm long; petiole variegated green and white. Blade hastate-sagittate, sparsely armed below, c. 30 cm long; anterior lobe subequalling the posterior ones; posterior lobes slender, to 6 cm wide, their midribs naked in the sinus for c. 3 cm, the lesser venation somewhat prominent below; costae of the anterior lobe arising near the sinus, curvinerved, running to the margin near the tip.²
INFLORESCENCE:
Peduncle similar to but exceeding the petiole, to 90 cm long. Spathe lanceolate, c. 7 cm long, hood-forming in the upper quarter, green, the major venation parallel and distant, the secondary venation reticulate; spadix orange, 4 cm long, with a 5 mm stipe adnate to the spathe. Flowers tetramerous; anthers exserted from the tepals at male anthesis and apparently retracting afterwards; stigmas hardly exceeding the tepals; ovule solitary. Fruit and seed unknown.²
ECOLOGY:
Ridge-crest rainforest at 150 m.²
DISTRIBUTION MAPS:
Hay 1988 Fig. 3.
ETYMOLOGY:
Commemorates the entomologist and biogeographer J. Linsley Gressitt and his wife Margaret, who died together in an air crash in China in April 1982; it was through Gressitt, at the Wau Ecology Institute, that Hay was first introduced to tropical vegetation. Hay spelt the epithet gressittorum; POWO and the World Checklist correct it to gressittiorum, the genitive plural for two people, and IPNI keeps the original spelling.²,¹
NOTES:
1. The hooded (cucullate) spathe is unique in the genus, and the only species with a green spathe and an orange spadix.²
2. The second Louisiade endemic, with C. brassii of Rossel Island; both are tetramerous members of the Merkusii group.²
3. Still known from the one collection of 1956 as far as the sources consulted show.⁴ ⚠
STORY:
STORY TITLE: One gathering, one hooded spathe, no photograph
Known from a single collection, on Sudest in the Louisiades. Its spathe is hooded, the only one in the genus that is.
Everything ever written about the species descends from that one gathering. Nobody has photographed the plant alive, and as far as the sources reach, nobody has collected it again.
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Cyrtosperma gressittiorum.
2. Hay, A. 1988. Cyrtosperma (Araceae) and its Old World allies. Blumea 33: 427–469 — protologue, p. 439.
3. iNaturalist: Cyrtosperma gressittiorum
4. GBIF occurrence download for Cyrtosperma, 2026-09-05 (3 records)
Fig. 4, drawn by Rosemary Wise, is from the protologue, Hay 1988, Blumea 33: 427–469