Triphyophyllum

Triphyophyllum peltatum is a facultatively carnivorous,^[2] up to 60 m tall vine^[3] in the monotypic genus Triphyophyllum /ˌtrɪfioʊˈfɪləm/ in the family Dioncophyllaceae native to tropical western Africa, in Guinea, Ivory Coast, Liberia, and Sierra Leone^[4] where it grows in tropical rainforest.^[3]

Triphyophyllum
Climbing adult Triphyophyllum with hooked leaves
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Dioncophyllaceae
Genus:	Triphyophyllum Airy Shaw
Species:	T. peltatum
Binomial name
Triphyophyllum peltatum (Hutch. & Dalziel) Airy Shaw
Triphyophyllum is native to Guinea, Ivory Coast, Liberia, and Sierra Leone[1]
Synonyms[1]
Dioncophyllum peltatum Hutch. & Dalziel

Description

Flower, Fruit and ripe seed of the adult plant

Juvenile non climbing insectivorous stage of Triphyophyllum with entire leaves and a single glandular insectivorous leaf resembling those of Drosophyllum

Unfurling tip of a juvenile insectivorous leaf with stalked glands in the SEM

Vegetative characteristics

It is a facultatively carnivorous,^[2] heterophyllous,^[5] up to 60 m tall vine^[3] with glabrous, terete stems.^[6] It has a three-stage lifecycle, each with a different shaped leaf, as indicated by its Greek name. In the first stage, T. peltatum forms a rosette of simple lanceolate Dracaena-like leaves about 18 cm (7.1 in) in length with undulate margins. At times when there is insufficient phosphorus in the soil^[7][8] it develops long, slender, glandular, circinate leaves up to 35 cm (14 in) in length and bearing two sorts of glands, and resembling those of the related Drosophyllum, which capture insects; there being one to three of these leaves in each rosette.^[9] In the plant's adult liana form it has short non-carnivorous leaves bearing a pair of "grappling hooks" ^[10] at their tips on a long twining stem which can become 50 metres (160 ft) in length and 10 centimetres (3.9 in) thick.^[11][12] T. peltatum is the largest of all confirmed carnivorous plants in the world, but its carnivorous nature did not become known until 1979, over 50 years after the plant's scientific description.^[5]

Generative characteristics

The axillary,^[13][14] branched,^[15] cymose, few-flowered^[14] or many-flowered inflorescence bears up to 80 small, ephemeral,^[15] fragrant,^[13] white to pink,^[15] bisexual, actinomorphic, pedicellate flowers.^[14] The pedicel is up to 3 cm long. The flower has 5 triangular, 2 mm long sepals, and 5 obovate, 13 mm long petals.^[14] The androecium consists of 10 stamens.^[14][6] The style is very short.^[6] The up to 4 cm wide, 1-seeded,^[14] 4–5-valved capsule fruit^[6][14] bears discoid, papery,^[14] flat, winged, circular, pink to red,^[13] 5–8^[6](–10) cm wide seeds^[16][13] with an up to 5.5 cm long funiculus extending beyond the fruit.^[14] Most of the seed's development occurs outside the fruit.^[17] The seeds are wind-dispersed.^[6][18]

Cytology

The chromosome count is 2n = 24,^[6][14] 36.^[14]

Taxonomy

Triphyophyllum peltatum was first described as Dioncophyllum peltatum Hutch. & Dalziel by John Hutchinson and John McEwan Dalziel in 1927.^[1] It was moved to a new monotypic genus Triphyophyllum Airy Shaw as Triphyophyllum peltatum (Hutch. & Dalziel) Airy Shaw by Herbert Kenneth Airy Shaw in 1952.^[4][1]

Etymology

The generic name Triphyophyllum is derived from triphyes meaning of threefold form,^[19] and phyllum meaning leaf.^[20] It refers to the three growth stages of the plant with three different types of leaves.^[7] The specific epithet peltatum means shield-like^[21] and refers to the discoid seeds,^[18] which have a long stalk that extends the seed beyond the capsule fruit.^[14]

Distribution and habitat

Triphyophyllum is found in Guinea, Ivory Coast, Liberia, and Sierra Leone,^[4] where it occurs in primary^[6] and old secondary dry evergreen rainforests. The habitat has a 6–7 month dry season. The acid, nutrient-poor soil is shallow.^[5]

Conservation

It is a rare and endangered species.^[7]

Cultivation

Triphyophylum peltatum is difficult to cultivate.^[7][22] It is cultivated in several botanical gardens: Würzburg, Hannover,^[23] Abidjan, Bonn, Cambridge University and Würzburg^{[citation needed]}, and is exceedingly rare in private collections.

Uses

Triphyophyllum compounds; top left: R = -H: Habropetalin A; R = -OH: Dioncophyllin A.; bottom left: Dioncophyllin; bottom right: Dioncophyllin C.

Triphyophyllum peltatum is traditionally used in folk medicine in the treatment of elephantiasis,^[14][6] and malaria.^[6] It produces many pharmaceutically active secondary metabolites, some of which have been found to have strong antiplasmodial activity. Some metabolites were found to have antitumoral and anti-multiple myeloma activity.^[7] The stems are used as tying material.^[14]