This genus comprises approximately 100 species of orchids found in the tropical areas of the Indian subcontinent, Southeast Asia, China, New Guinea, and various islands in the western Pacific. Characterized by robust green foliage and erect stems, these plants bear clusters of fine flowers that come in a range of colors.

Cleisostoma

Cleisostoma arietinum

Cleisostoma filiforme is an evergreen, tropical epiphytic orchid that can range in size from small to large. Its slender, stem-like rhizomes are densely packed with alternating sheaths that bear green leaves. The leaves are narrow, resembling pencils, approximately 0.5 cm in width, with varying lengths. During the summer, the plant produces pendulous, arching inflorescences that can reach lengths of up to 25 cm, each bearing as many as thirty small, glossy flowers. Each blossom measures between 1 and 1.2 cm across, featuring petals and sepals in shades of brown-red or burgundy, while the center displays a yellow hue. The lip of the flower is white with a hint of pink.

Cleisostoma filiforme

Cleisostoma paludosum

Cleisostoma paniculatum is a compact, evergreen orchid native to tropical regions, thriving as an epiphyte. Its growth habit features stem-like rhizomes that are densely wrapped in alternate sheaths that support the leaves. The leaves, which can reach lengths of up to 15 cm and widths of 2 cm, exhibit a green to dark green coloration. New leaves emerge from the tips of the stems, while older leaves gradually shed from the lower sections. This orchid typically blooms in winter and early spring, producing angled, branched flower stems that can grow between 20 and 30 cm long. Each stem can bear as many as twenty small, waxy flowers that open sequentially. The petals and sepals display a yellow hue accented with brown-red markings.

Cleisostoma paniculatum

Cleisostoma racemiferum

Cleisostoma roseum

Cleisostoma sagittiforme

Cleisostoma schlechteri is a medium to large evergreen epiphytic orchid native to tropical regions. Its stem-like rhizomes are densely wrapped in alternate sheaths that bear green leaves. The linear, leathery foliage can reach lengths of up to 17 cm and widths of 3-4 cm. As new leaves develop at the apex of the stem, the older ones below gradually drop away. Roots emerge from the stem, extending upwards in alignment with the plant's growth pattern. The flowering stems can grow to 50 cm in length, displaying a pendulous and branched structure adorned with numerous small, yellowish-green flowers that feature a distinctive white spur.

Cleisostoma schlechteri

Cleisostoma subulatum is a medium-sized, evergreen orchid that thrives as an epiphyte in tropical environments. Its stem-like rhizomes are densely wrapped in alternate sheaths that bear green leaves. The leaves themselves are leathery and robust, exhibiting variability in shape; they can range from broad and linear to slender and pencil-like, typically measuring between 13 to 17 centimeters in length. As new foliage emerges from the apex of the stem, older leaves naturally shed from the bottom. The plant develops new roots along its rhizomatous stems, following an upward growth pattern. Flowers emerge on rigid, drooping stems that can reach up to 17 centimeters in length. Each flower, less than a centimeter wide, blooms sequentially, displaying a glossy yellowish-green hue adorned with brown-red markings and a prominent white spur.