Holcoglossum wangii

Description

Holcoglossum wangii is a species of asparagus plant. This was first described by Eric Alston Christenson. Holcoglossum wangii belongs to the genus Holcoglossum, and family Orchidaceae. All species of this genus are perennial epi- or lithophytes and are characterized by a short monopodial shoot axis with terete or cross-sectionally triangular leaves. The upper side forms a groove with the folded edges of the leaves. The leaves are tapered and not notched at the leaf tip. The root tips of living roots show a reddish color in all species of the genus, and some species also have red-spotted foliage. The flowering stem emerges laterally from the shoot axis and forms two or more flowers, which are far apart and form a raceme or inflorescence. The flowers are white and wide open. The lip is three-lobed. The lateral lobes are erect and dotted adaxially. The central part is spread out over a large area and is parallel to the gynostemium. The lip is shaped to allow potential pollinators to depress the middle lip. The flowers have an elongated spur, which is strongly reduced in the subgenus Brachycentron. The gynostemium has a large scar area. The stamen contains two separate pollina. The stipes connecting the pollina and the adhesive disc (Viscidium) bend in the middle when removed from the rostellum. The rostellum is deeply incised.The number of chromosomes is 2n = 38 in almost all species. Holcoglossum tsii has 76 chromosomes in the diploid chromosome set (2n = 76). Self-pollination has been observed in Holcoglossum amesianum, in which the pollina moves independently to the fertile stigma in the column. The distribution area of the genus extends over southwest China, Laos, Vietnam, Thailand and Malaysia. However, most of the species come from the Yunnan province in the south-west of the People's Republic of China. Holcoglossum quasipinifolium and Holcoglossum pumilum are endemic to Taiwan. The species live at higher altitudes between 1200 m and 3300 m and thus prefer a cool to cold habitat.