| Isoetes capensis | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Lycophytes |
| Class: | Lycopodiopsida |
| Order: | Isoetales |
| Family: | Isoetaceae |
| Genus: | Isoetes |
| Species: | I. capensis |
| Binomial name | |
| Isoetes capensis | |
Isoetes capensis, the cape quillwort, is a species of quillwort from South Africa.
The cape quillwort is a tufted geophyte with horny toothed scales. [1] It has between 5 and 35 leaves that bear sporangia. These are held at a 45-degree angle. This is unusual as most species have perpendicular leaves. [2] These are slender (4 mm (0.16 in) at the base) and reach a length of up to 20 cm (7.9 in), with a heart-shaped appendage (ligule) at the base. [1] [2] The ligule is up to 1 mm (0.039 in) long and pale, although it is darker at the point of attachment. [2] The sporangia are completely covered in a thin membrane. [1] They have a diameter of 2–5 mm (0.079–0.197 in) and are oval or round in shape. [2]
This species shows immense variability in its spores. The surface ranges from having irregular tubercules to interconnected ridges to being covered in a net-like structure of ridges. All of these surface sculptings may be found in a single population. [3] They grey-white megaspores have a diameter of 0.39–0.57 mm (0.015–0.022 in). [2]
This species has a three lobed pseudocorm. The dark brown leathery bud scales are triangular and have dimensions of about 3 by 3 mm (0.12 by 0.12 in). They may also have a hair that is about 3 mm (0.12 in) long. [2]
The cape quillwort is endemic to the Western Cape of South Africa. [4] It is found between Darling, Stellenbosch and Worcester and an altitude of up to 300 m (980 ft). It grows on sandy clay soils in low areas that experience seasonal flooding as well as around vleis. [1] There are nine subpopulations with combined area of occupancy of 44–56 km2 (17–22 sq mi). [5] At least one specimen has also been recorded from Somerset West. [6]
While it may form colonies, this species is often difficult to find as it grows amongst grasses. [2]
This is a seasonal species. It disappears when the area it is growing in dries up, leaving behind only the pseudocorms. Each pseudocorm is protected by a series of overlapping brown scales, which remain as a leathery structure surrounding the new leaves that appear in the next wet season. [3] Specimens have, however, been found to live for more than three years in kept submerged in water. This kind of immersion did not result in any elongation of the leaves or any other changes in the form of the specimens. [3]
This species is considered to be endangered by the South African National Biodiversity Institute. While the largest subpopulation is made up of between 500 and 1000 individuals, most subpopulations have fewer than 100 plants. When assessed in 2018, it was estimated that 760-3740 individuals remain and that the population is continuing to decline. While this species is easily overlooked, little of its habitat remains and what habitat is left is continuing to decline and deteriorate. This species is also threatened by urban and agricultural expansion, disrupted water systems, eutrophication and alien species. [5]
In 1955 the University of Cape Town Lecturer Edith Stephens donated a piece of land (now known as the Edith Stephens Wetland Park) in an attempt to preserve the type population of the cape quillwort. [7] It is currently, however, rare in this protected area. A census in 2009 found only ten remaining individuals. [2]
Agapanthus africanus, or the African lily, is a flowering plant from the genus Agapanthus found only on rocky sandstone slopes of the winter rainfall fynbos from the Cape Peninsula to Swellendam. It is also known as the lily-of-the-Nile in spite of only occurring in South Africa.
Isoetes, commonly known as the quillworts, is a genus of lycopod. It is the only living genus in the family Isoetaceae and order Isoetales. There are currently 192 recognized species, with a cosmopolitan distribution mostly in aquatic habitats but with the individual species often scarce to rare. Some botanists split the genus, separating two South American species into the genus Stylites, although molecular data place these species among other species of Isoetes, so that Stylites does not warrant taxonomic recognition. Species virtually identical to modern quillworts have existed since the Jurassic epoch, though the timing of the origin of modern Isoetes is subject to considerable uncertainty.
Isoetes lacustris, the lake quillwort or Merlin's grass, is a boreal quillwort native on both sides of the northern Atlantic Ocean. Synonyms include Isoetes hieroglyphica.
Isoetales, sometimes also written Isoëtales, is an order of plants in the class Lycopodiopsida.
Alsophila capensis, synonym Cyathea capensis, is a regionally widespread and highly variable species of tree fern. It is indigenous to Southern Africa and South America.
Felicia amelloides, the blue daisy bush or blue felicia, is a hairy, soft, usually perennial, evergreen plant, in the family Asteraceae. It can be found along the southern coast of South Africa. It grows as ground cover and produces many very regular branches. It mostly grows to about 50 cm (1.6 ft) high, rarely to 1 m. The leaves are oppositely arranged along the stems, dark green in colour and elliptic in shape. The flower heads sit individually on up to 18 cm (7 in) long, green to dark reddish stalks. They consist of about twelve heavenly blue ray florets that surround many yellow disc florets, together measuring about 3 cm across. It is also cultivated as an ornamental, and was introduced in Europe in the middle of the 18th century.
Felicia aethiopica is a low shrublet of up to about 50 cm high that is assigned to the family Asteraceae. It has rigid, leathery, inverted egg-shaped leaves, with only the lowest pair set oppositely. It has flower heads with an involucre of about 8 mm in diameter with bracts that each contain three resin ducts, and have one whorl of twelve to fourteen ray florets with about 11 mm long and 1½ mm wide blue straps surrounding many yellow disc florets. The plant is called wild aster or dwarf Felicia in English, and wilde-aster or bloublombossie in Afrikaans. Flowering occurs year-round. Wild aster can be found in the Western and Eastern Cape provinces of South Africa.
Isoetes bolanderi, or Bolander's quillwort, is a species of quillwort, a type of lycophyte. This aquatic plant is native to high altitude regions of the western United States and southern Alberta. It grows almost entirely underwater in lakes and other water bodies from a corm-like stem, which remains buried in the mud, producing up to twenty pointed, cylindrical leaves approaching 15 centimeters in maximum length. It reproduces via spherical sporangia, covered about one third by the velum. The ligule is small and heart-shaped. The megaspores are white, though sometimes bluish, and 350 to 290 micrometers in diameter. The microspores are 25 to 30 micrometers long.
Isoetes howellii, or Howell's quillwort, is a species of quillwort, a type of lycophyte. It is an aquatic plant native to North America.
Isoetes nuttallii, or Nuttall's quillwort, is a species of quillwort, a type of lycopod. It is native to shallow waters and other wet habitats of western North America from British Columbia to California. It produces up to 60 pointed, cylindrical, green to gray-green leaves, each 7 to 17 centimeters long. The velum completely covers the spherical sporangia, which are 5 millimeters long and 1.5 millimeters wide. The ligule is small and triangular. The megaspores are 400 to 500 micrometers in diameter. The microspores, which are spiny and covered in tubercles, are 28 to 31 micrometers long.
Isoetes eludens is an aquatic plant in the genus commonly known as quillwort that is native to the Kamiesberg Mountains in Namaqualand, South Africa. So far it is known to grow only in a single !gau (gnamma), a small temporary pool formed in a hollowed out area of granite rock. It has likely been growing in that region for millions of years, but was only discovered in 2007 and described in 2009. The specific epithet eludens refers to the fact that it eluded discovery, in spite of several searches in recent years in the area for new quillwort species.
Isoetes echinospora, also known as spiny quillwort, spiny-spored quillwort or spring quillwort is a species of quillwort in the Isoetaceae family, and is the most abundant species in Canada. It can be found in shallow aquatic environments from Labrador and Newfoundland to Alaska, and south to Pennsylvania, Wisconsin, Michigan, Colorado, and California. In Germany it is found in only two locations: the Feldsee and Lake Titisee, both in the High Black Forest.
Isoetes riparia, the shore quillwort, is a species of plant in the family Isoetaceae. It can be found in rivers, creeks, and tidal mud flats in southern Quebec and southeastern Ontario, south to eastern New York. It has 5 to 35 long, erect bright green to yellow-green leaves, which are 6 to 35 centimeters long. The velum covers one fourth of the sporangium, which can be 7 millimeters long and 4 millimeters wide. The elongated ligule can grow to be 3 millimeters long. The spherical megaspores are 430 to 680 micrometers in diameter with closely set ridges. The kidney-shaped microspores are 24-35 micrometers long, and usually have spine-tipped tubercules. The megaspores can sometimes come to resemble that of either I. echinospora, if the megaspores become eroded and bear projections that could resemble spines, or I. macrospora, if the broken ridges take a certain shape.
Isoetes macrospora, the big-spore quillwort, is a species of quillwort in the Isoetaceae family. It can be found in the deep water of low nutrient lakes in the Precambrian Shield as well as in Newfoundland, Nova Scotia, Quebec, and Ontario. In the United States, it has been found in Minnesota and south, through the Appalachian Mountains to Virginia. It bears 3 to 17 long, stiff dark green leaves, sometimes with recurving tips. The sporangium can be 5 millimeters long and 4 millimeters wide, covered from one sixth to one quarter by the velum. The triangular ligule can grow up to 2 millimeters long. The spherical, white megaspores are 400 to 800 micrometers in diameter, and bear ridges that form honeycomb-like areas. The kidney-shaped microspores are 32 to 50 micrometers long, each with evenly spaced smooth papillae.
Isoetes occidentalis, the western quillwort, is a species of quillwort in the family Isoetaceae. It can be found in aquatic habitats of coastal Alaska and British Columbia south to California and Colorado. It is frequently found on Vancouver Island and around the Fraser Valley region. It bears 10 to 30 or more rigid, dark green leaves, each 5 to 20 centimeters long. The velum covers one fourth to one third of the orbicular sporangium, which is 5 to 6 millimeters in diameter. The ligule is shaped like a shortened triangle. The white megaspores are 500 to 700 micrometers in diameter and bear sharp ridges and crests. The microspores are 36 to 43 micrometers long. Though the leaves seem to bear resemblance to those of I. lacustris, especially the occasionally occurring reddish base, I. occidentalis is a hexaploid and I. lacustris is a decaploid.
Lobostemon montanus, the turquoise bush bugloss, mountain lobostemon or agtdaegeneesbos, is a South African species belonging to the forget-me-not family.
Lobostemon collinus, the pyjamabush or iron healthbush, is a species belonging to the forget me not family. It is known only from the fynbos biome of the Western Cape of South Africa.
Isoetes stellenbossiensis, the Stellenbosch quillwort or Cape Flats quillwort, is a species of plant from South Africa.
Isoetes stephanseniae, the granite quillwort, is a species of quillwort from South Africa, named for A. J. Stephansen, who discovered it in 1927. Of very limited distribution, it is known to survive only as one population in seasonal pools over granite near Stellenbosch, where it is threatened by the encroachment of alien species and eutrophication from the sewage works on whose grounds it grows. Like other quillworts, it bears a tuft of leaves with distinctively sculpted megaspores. It is most similar to Isoetes capensis, the cape quillwort, which occurs in the same province; both hold their leaves at a 45-degree angle, unlike most South African quillworts which have leaves stiffly erect.
{{cite book}}: CS1 maint: others (link)