''Romulea monadelpha'' is a herbaceous perennial
geophyte
A storage organ is a part of a plant specifically modified for storage of energy
(generally in the form of carbohydrates) or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have ...
in the family
Iridaceae
Iridaceae is a family of plants in order Asparagales, taking its name from the irises, meaning rainbow, referring to its many colours. There are 66 accepted genera with a total of c. 2244 species worldwide (Christenhusz & Byng 2016). It inclu ...
native to
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring count ...
. It has a small corm in the soil, a few thread-like leaves, and
trimerous Merosity (from the greek "méros," which means "having parts") refers to the number of component parts in a distinct whorl of a plant structure. The term is most commonly used in the context of a flower where it refers to the number of sepals in a w ...
dark red flowers with elaborate markings on the inside near the bottom of the flower. It is called karoo satynblom in
Afrikaans
Afrikaans (, ) is a West Germanic language that evolved in the Dutch Cape Colony from the Dutch vernacular of Holland proper (i.e., the Hollandic dialect) used by Dutch, French, and German settlers and their enslaved people. Afrikaans g ...
.
Description
''Romulea monadelpha'' is a low
geophyte
A storage organ is a part of a plant specifically modified for storage of energy
(generally in the form of carbohydrates) or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have ...
of high, with a subterranean stem that grows from a corm with a rounded base, which has a tunic with curved acuminate teeth. Its three to five thread-like leaves grow directly out of the soil and are in diameter, and have four grooves along their lengths. Its flowers sit individually at the tip of a flower stalk (or
pedicel
Pedicle or pedicel may refer to:
Human anatomy
*Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures
...
) and are subtended by two bracts that both mostly have brown papery margins. The outer bract usually has one keel on the upper side and a narrow papery margin, the inner bract has two keels with a wider papery margin. The
trimerous Merosity (from the greek "méros," which means "having parts") refers to the number of component parts in a distinct whorl of a plant structure. The term is most commonly used in the context of a flower where it refers to the number of sepals in a w ...
flowers are without scent, burgundy red with elaborately colored blotches with black and cream in the cup, but the population around the Gannaga Pass population has salmon colored flowers and large black and light grey markings. The six
tepal
A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...
s are oval and may be slightly indented at the tip, 2½–4 cm (1–1.6 in) long. The three
filaments are oblong in shape and are firmly pressed together or even fused to form a column of long, mostly without hairs and topped by 1–1½ cm long
anthers
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10
Morphology and terminology
A stamen typically consists of a stalk called the filam ...
. When the fruit is ripe, the flower stalk is curved. The flowers of this species can be found in August and September.
Comparison with related species
''Romulea monadelpha'' has short, oblong, black filaments that are pressed together or fused, while ''
R. sabulosa'' has slender, tapering, mostly pale green filaments. The flower stalk of ''R. monadelpha'' is stout and has one flattened side while in ''R. sabulosa'' the stalk is slender, more or less circular in cross section does not curve when the fruit is ripe. The species occur in the same area near Nieuwoudtville, but have a different habitat: ''R. monadelpha'' grows on heavy dolerite clay while ''R. sabulosa'' occurs only on a light sandy clay known as
tillite
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...
.
Taxonomy
This species was first described by the English botanist
Robert Sweet in 1830 as ''Trichonema monadelphum''. In 1892,
John Gilbert Baker
John Gilbert Baker (13 January 1834 – 16 August 1920) was an English botanist. His son was the botanist Edmund Gilbert Baker (1864–1949).
Biography
Baker was born in Guisborough in North Yorkshire, the son of John and Mary (née Gi ...
assigned the species to ''Romulea'', creating the
new combination
''Combinatio nova'', abbreviated ''comb. nov.'' (sometimes ''n. comb.''), is Latin for "new combination". It is used in taxonomic biology literature when a new name is introduced based on a pre-existing name. The term should not to be confused wi ...
''Romulea monadelpha''.
''R. monodelpha'' is the type species of both the
subgenus
In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus.
In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed betw ...
''Spalanthus'' and the
section
Section, Sectioning or Sectioned may refer to:
Arts, entertainment and media
* Section (music), a complete, but not independent, musical idea
* Section (typography), a subdivision, especially of a chapter, in books and documents
** Section sign ...
''Spalanthus''.
Habitat and ecology

''Romulea monadelpha'' exclusively grows on
dolerite
Diabase (), also called dolerite () or microgabbro,
is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grained ...
clay in the western
Karoo
The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe !Orakobab or Khoemana word ''ǃ’Aukarob'' "Hardveld") is a semi- desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its ...
near the
escarpments
An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations.
The terms ''scarp'' and ''scarp face'' are often used interchangeably with ''escar ...
.
It is only known to be pollinated by the
monkey beetle
Monkey beetles are scarab beetles, a group of several genera within the tribe Hopliini. The placement of this tribe within the family Scarabaeidae is uncertain between Melolonthinae and Rutelinae. Many species visit flowers for pollen and necta ...
''Clania glenlyonensis''.
Distribution
An endemic of the
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of the Kgalagadi ...
province of South Africa, ''R. monadelpha'' occurs along the
Bokkeveld and
Roggeveld
The Roggeveld ( Afrikaans for "rye field") is a plateau in the Karoo region of the Northern Cape, South Africa. Its name comes from the wild rye once plentiful in the area. The Roggeveld Mountains, west of the plateau in the Northern Cape
T ...
escarpments from near
Nieuwoudtville
Nieuwoudtville is a town in Namakwa District Municipality in the Northern Cape province of South Africa. The town lies on the Bokkeveld Escarpment, and was established in 1897. The Nieuwoudtville Falls
Nieuwoudtville is a town in Namakwa Di ...
southwards as far as the top of the Gannaga Pass near Middelpos in the south.
References
{{Taxonbar, from=Q15581197
Endemic flora of South Africa
monadelpha
Plants described in 1830
Taxa named by Robert Sweet (botanist)
Taxa named by Ernst Gottlieb von Steudel
Taxa named by John Gilbert Baker