Aglaonema costatum

About

Aglaonema costatum, called the spotted evergreen, is a species of flowering plant in the genus Aglaonema, native to Bangladesh, Thailand, Peninsular Malaysia, Laos, Cambodia and Vietnam. In these areas, the plant is typically found growing in the understory of tropical rain forests. Its putative form, Aglaonema costatum f. immaculatum, called the unspotted Chinese evergreen, has gained the Royal Horticultural Society's Award of Garden Merit.

Summary from Wikipedia