Holothrix is a genus of 55 species in the Orchidaceae family that occurs in Africa. Species are tuberous and have minute flowers and one or two often hairy, round to oval leaves that grow flat on the ground. Stems are usually hairy. Petals and lips are often multilobed. Flowering usually occurs in spring or summer, but there are species that grow in winter rainfall, summer rainfall, and both.
Holothrix aspera (Lindl.) Rchb.f. is found in deep sandy soils or rock pavements from Namaqualand and the western Karoo to Swellendam, South Africa. It is a winter rainfall species that grows to 10 cm and has two round leathery leaves that are pressed to the ground. The white flowers on hairy spikes have a lip that is divided into 5 to 7 rounded lobes, with a short curled spur. Photo 1 was taken by Mary Sue Ittner in the Komsberg of what she believes is this species. Photos 2-3 taken September 2011 near Carolusberg in Namaqualand by Cameron McMaster. The last photo is from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok.
Holothrix exilis Lindl. is found in coastal regions of the southern Cape. It grows to 29 cm and flowers spring to autumn (October to March) with a scape with soft spreading hairs, two basal ovate sparsely hairy leaves and few to many tiny green flowers in a dense raceme. In the Little Karoo it is found in seasonally moist, rocky sandy soils in Fynbos. Photo from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok.
Holothrix grandiflora (Sond.) Rchb.f. is distributed from the west coast to the Eastern Cape where it is found on rock crevices. Growing to 30 cm high, it has two basal ovate leaves, often withered at flowering, and large creamy white flowers often tinged apricot pink. The lip is trumpet-like and prominently fringed into 5-9 filiform lobes. It flowers in March, probably best in good rain years. Photo from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok.
Holothrix incurva Lindl. is found in damp crevices and ledges in cliffs at 1500 to 2900 meters in the summer rainfall Drakensberg Mountains in South Africa. It has yellowish hairy sepals and a hairy leaf and stem. The lip of the flowers is deeply divided into 5 slender lobes. Photos taken by Cameron McMaster at Sentinel Peak. In one of the photos this species is pictured with Hesperantha scopulosa.
Holothrix pilosa (Burch. ex Lindl.) Rchb.f. grows to 55 cm when in flower from spring to autumn (November to March). It is found in dry, stony places in the southern Cape. It has two basal ovate leaves that are densely hairy underneath. Flowers are a creamy white with a green central line. Photo from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok.
Holothrix schlechteriana Kraenzl. ex Schltr. is found among rocks and shrubs from Namaqualand to the Eastern Cape. Growing to 27 cm, it has two basal ovate leaves and white to yellow green flowers with a prominently fringed lip in a dense raceme. It flowers October to February. It has smaller flowers than Holothrix grandiflora. Photo from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok.
Holothrix scopularia Rchb.f. is found on exposed, often rocky, grassland at higher altitudes in the Eastern Cape of South Africa in the Drakensberg Mountains. It grows to 34 cm and is covered in spreading hairs. The inflorescence is dense with small white to dull yellow or pink flowers all arranged on one side. The lip is deeply divided into 5 to 11 slender lobes. Photos taken by Mary Sue Ittner and Cameron McMaster on Naude's Nek in the Drakensberg.
Holothrix secunda (Thunb.) Rchb.f. is a widespread species that is found on dry rocky slopes and pavements in the Northwest and Southwest Cape to the Western Karoo and the Little Karoo. Growing to 30 cm, it has two basal ovate fleshy leaves and creamy white flowers with a lip that has five spreading lobes. It flowers from winter to spring (June to October.) The first photo from the book Plants of the Klein Karoo courtesy of Jan and Anne Lise Schutte-Vlok. The other photos were taken by Cameron McMaster at Elands Bay (southwest coast).
Holothrix thodei Rolfe grows in moist rocky grassland or rock crevices from 1500-2600 meters in the summer rainfall Drakensberg Mountains in South Africa. It has hairy leaves and yellowish to brownish green flowers with a short 3-lobed lip and a stem with long downward pointing hairs. It blooms January through March. Photos taken by Cameron McMaster at Aurora Peak, Maclear.
Holothrix villosa Lindl. is found on sandstone and granite slopes and pavements. It is widespread, occurring from Namaqualand, the Western, Southern, and Eastern Capes and the Western Karoo of South Africa to Zimbabwe. It therefore occurs in both summer and winter rainfall areas. It has 2 basal ovate hairy leaves and minute green flowers in a dense raceme. It flowers August to November. Photos taken near Caledon and Napier in the Overberg by Cameron McMaster.
