General Information

COMMON NAMES: Dryland Taro, Tannia, Tanier, Yautia, Ocumo; Micky Mouse Taro and Stingray Plant [for cv Albomarginatum Monstrosum]; German Tania, Okumo TRADITIONAL NAMES: Taruā / Taro Taruā (RR), Taruā (MG AT MK MT), Tarotaruā (AK), Taro Taruā / Taruā (RK) GLOBAL DISTRIBUTION: NATIVE n.S.America. COOK ISLANDS STATUS: Introduced - Recent (c.1900), Not naturalised; S.Group widespread but declining; N.Group (rare); Land, lowlands, horticultural SIGNIFICANCE LIST: ; Some varieties locally lostFood (Root 4+) KEY FEATURES: A taro-like herb to 1.5m with massive horizontal leaves (to 1m), posterior lobes not joined, and with a conspicuous vein near the margin - these features separating it from Wetland Taro (Taro) and from Giant Taro (Kape). The central tuber (or corm) is acrid, while the surrounding tubers are more edible, varying from white to orange or purplish. An ancient horticultural plant of tropical America, where common names are Tannia, Yautia, Ocumo and Malanga. Introduced by the London Missionary Society as a "dryland" substitute for swamp-grown Wetland Taro. Known as Taruā in Tahiti and the Cook Islands. SIMILAR SPECIES: Xanthasoma undipes (=X. jacquinii) (Fiji, possibly Cooks) has posterior mid-ribs denuded for a few cm from stalk-blade junction (vs. covered by leaf-blade); leaf-stalk sheath wavy (vs. smooth); upper spathe with violet (vs. not green-white)

Cook Islands Distribution

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Southern Group: Present    Makatea: Present
RR	MG	AT	MK	MT	AK	PL	TK	MN
+++	++++	++	+?X?	+?X?			=	-

Northern Group: Present
TN	MH	RK	PK	NS	SW
-	-	+	-	-	-

Xanthosoma sagittifolium Linnaeus
SYNONYMS: Xanthosoma violaceum [sensu]; Xanthosoma nigrum [sensu AW]; Arum sagittifolium [O]; Xanthosoma atrovirens [an illegitimate name]

TAXONOMY: PLANTAE; ANTHOPHYTA (=Angiospermae); LILIOPSIDA (=Monocotyledones); ARECIDAE; Arales; ARACEAE

SIGNIFICANCE NOTES -
BIODIVERSITY: Some varieties locally lost. Comment: In teh NBSAP this plant was listed as the second most endangered domestic plant on Mauke. The Plant Genetic Resources Workshop (Rarotonga, August 2003) recorded that it was lost from Mauke and Mitiaro, declining on Atiu, but still very abundant on Mangaia. Reasons given for decline were damage by pigs and worms. It was noted that it was not as preferred as Taro, but that it had a better shelf-life than Taro and improved with storage.
POSITIVE SIGNIFICANCE: Food (Root 4+)

IDENTIFICATION: A large-leaved herb to 1.5m. ROOTS a central tuber surrounded by smaller ones. LEAVES hairless and waxy above, massive (to 1m), arrow-shaped leaf with sharp-tipped basal lobes, and a distinct vein near and parallel to the edge of the leaf; leaf-stalk to 1m with pale wax. FLOWER lower spathe green to 7cm, persistent; upper spathe (=limb) greenish-white to 15cm, withering. Cultivars: 'Albomarginatum Monstrosum' = mottled white-cream, tip funnel-like with long extension (=Mickey Mouse Taro, Stingray Plant).

GENERAL NOTE: Secondmost important aroid food crop in the world after Wetland Taro. Dryland Taro (Taruā) is a Missionary introduced plant from Tropical America, where it is known in different areas as Yautia, Tannia, Malanga and Ocumo. It is commonly grown in the Agricultural Belt, and scattered plants are seen in the inland valleys at low elevations.

Vouchers:
None Recorded.

References:
p.161 Neal - In Gardens of Hawaii
p.1175 Hortus 3rd
p.1225 Royal Hort. Soc. Index of Garden Plants
p.124 Tropica
p.1/459 A.C.Smith - Flora Vitiensis Nova
p.27 RC Wilder - Flora of Rarotonga
p.401b Whistler - Ethnobotany of the Cook Islands
p.47 McCormack/Kunzle - Rarotonga's Mountain Tracks and Plants

Data Update History (information):
zTX, zB02, zM02, zupM04a, zD02

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