Xanthosoma

Xanthosomais a genus offlowering plantsin the arum family,Araceae. The genus is native to tropicalAmericabut widely cultivated and naturalized in other tropical regions.Several are grown for theirstarchycorms, an importantfood stapleof tropical regions, known variously asmalanga,otoy,otoe, cocoyam (or new cocoyam),tannia,tannier,yautía,macabo,ocumo,macal,taioba,dasheen,quequisque,ʻapeand (inPapua New Guinea) as Singapore taro (taro kongkong). Many other species, including especiallyXanthosoma roseum, are used asornamental plants; in popular horticultural literature these species may be known as ‘ape due to resemblance to the true Polynesian ʻape,Alocasia macrorrhizos, or as elephant ear from visual resemblance of theleafto anelephant's ear. Sometimes the latter name is also applied to members in the closely related generaCaladium,Colocasia(taro), andAlocasia.
The leaves of mostXanthosomaspecies are 40–200 centimetres (16–79 inches) long, sagittate (arrowhead-shaped) or subdivided into three or as many as 18 segments. Unlike the leaves ofColocasia, those ofXanthosomaare usually not peltate- the upper v-notch extends into the point of attachment of the leaf petiole to the blade.
The inflorescence inXanthosomais composed of aspadixwithpistillateflowers at the base, a belt of sterile flowers offered as a reward for pollinators in the middle andstaminateflowers on the upper part. Prior to opening, theinflorescenceis enclosed within a leaf-likespathe. When the inflorescence is ready to open, the upper part of the spathe opens and exposes the staminate area of the spadix; the basal area of the spathe remains closed, forming a spacious chamber (i.e., the spathe tube) that encloses the pistillate and sterile flowers (Garcia-Robledo et al. (2004,2005a,2005b)).
The inflorescences last for two nights and areprotogynousin some, but not all species.They change from the pistillate phase that attracts pollinators on the night it opens, to a staminate phase on the second night, when pollen is shed. When the inflorescence opens, it produces heat and releases a sweet scent attracting its pollinators,dynastinebeetles (Cyclocephalaspp.). Dynastines arrive covered with pollen from another inflorescence and remain in the spathe tube for 24 hours, pollinating the pistillate flowers as they feed on the sterile area of the spadix. On the second night, they come out of the tube and walk over the staminate flowers, getting covered with pollen, and then flying to a recently opened inflorescence nearby. (Garcia-Robledo et al. (2004,2005a,2005b)).
Fruit maturation takes several months. Fruits start to develop within the shelter of the spathe tube. When the infructescence
is mature, in some species, it arches back and downwards. In other species, it stays erect. Then, the tissue of the spathe tube rolls outwards, exhibiting the bright orange fruits and the velvety pink inner spathe surface.
The following species are accepted:
The name is derived from theGreekwordsξανθός(xanthos), meaning 'yellow', andσῶμα(soma), meaning 'body'. It refers to the stigma or yellow inner tissues.
Domestication ofXanthosomaspecies (especiallyX. sagittifoliumbut alsoX. atrovirens,X. violaceum,X. maffaffaand others) is thought to have originated in northern lowlandSouth America, then spread to theAntillesandMesoamerica. Today,Xanthosomais still grown in all those regions, but is especially popular inCuba, theDominican RepublicandPuerto Rico, where it is used inalcapurriasor boiled. It is grown inTrinidad and Tobago,GuyanaandJamaicato make the popularcallaloodish,and inSt. Kitts and Nevisto make tanniafritters.
It is also grown inWest Africa, now a major producer, where it can be used as a replacement foryamsin a popular regional dish calledfufu.
Xanthosomais also grown as a crop in thePhilippines.
Traditionally,Xanthosomahas been asubsistence cropwith excess sold at local markets, but in theUnited States, large numbers ofLatin Americanimmigrants have created a market for commercial production. In general, production has yet to meet demand in some areas. In Polynesia,Alocasia macrorrhizos(‘ape) was considered afamine food, used only in the event of failure of the much preferredtaro(kalo) crop.After having been introduced to Hawaii in the 1920s from South America,Xanthosomahas naturalized and has become more common thanA. macrorrhizos, and has been given the same name,ʻape.
The typicalXanthosomaplant has a growing cycle of 9 to 11 months, during which time it produces a large stem called acorm, this  surrounded by smaller ediblecormelsabout the size ofpotatoes. These cormels (like the corm) are rich in starch. Their taste has been described as earthy and nutty, and they are a common ingredient in soups and stews. They may also be eatengrilled,fried, orpuréed. The young, unfurled leaves of some varieties can be eaten as boiledleafy vegetablesor used insoupsandstews, such as the Caribbeancallaloo.
Flour made fromXanthosomaspecies ishypoallergenic.