Hylocereus Megalanthus
Hylocereus megalanthus is a cactus species in the genus Hylocereus that is native to northern South America, where it is known, along with its fruit, by the name of Pitahaya. The species is grown commercially for its yellow fruit, but is also an impressive ornamental climbing vine with perhaps the largest flowers of all cacti.
The yellow fruit has thorns, unlike the red dragon fruits (H. undatus, H. polyrhizus, H. costaricensis), and is commonly known as "yellow dragon fruit", "yellow pitahaya" or "yellow pitaya".Stems may lie along the ground (procumbent), climb (scandent), or hang (pendent). Stems are often only 1.5 cm thick, producing aerial roots; 3 ribs; margins slightly undulating; white areoles; 1-3 spines 2–3 mm long, yellowish; several hairs on young growth, brittle-like; green epidermis.Flowers are nocturnal and funnel-shaped, 32–38 cm long; pericarpel is ovoid or slightly globose, tubercles are large and flattened, with felt-like and spiny areoles subtended by small bracteoles; receptacle elongate; outer tepals long, green, triangular-acute; inner tepals 10 cm long, 3.5 cm wide, white, broader; stamens numerous inserted in two zones, yellow; style yellow, stigma lobes numerous, green.Fruit: ovoid, tuberculate, spiny, skin yellow (sometimes red/orange, when hybridized), seeds black; interior white (sometimes pink, when hybridised), edible, having a pleasant, mildly sweet flavour.Pollination: Yellow pitayas are self-fertile (meaning no cross-pollination is required).