Macrozamia heteromera
Dry sclerophyll woodlands·Low-trunked cycad·Not specified in text
Macrozamia heteromera is a species of cycad endemic to New South Wales, Australia, typically found in dry sclerophyll woodlands. This low-trunked cycad is characterized by its mid-green, narrow, and often divided pinnae, a feature that distinguishes it within the Macrozamia genus. While its seeds and leaves are toxic, traditional Indigenous Australian practices demonstrate that proper preparation can render the seeds edible.
Key Facts
- ›Endemic to New South Wales, Australia.
- ›Found in dry sclerophyll woodlands, particularly in the Warrumbungle Mountains and Coonabarabran district.
- ›Characterized by MID-green, narrow, and usually divided pinnae.
- ›Has a low trunk, typically under 1 meter in height.
- ›Seeds and leaves are toxic, containing the azoxyglycoside macrozamin.
- ›Indigenous Australians prepared seeds for consumption through roasting and washing.
New South Wales, Australia
Low trunk, usually below 1 meter in height, Trunk approximately 15–25 cm in diameter, Light green in colour, Covered with red wool when younger
- Mid-green colour
- Narrow pinnae
- Usually divided pinnae
- Moderately keeled leaves
- Leaves grow to around 50–90 cm long
- Composed of up to 60 to 100 pinnae
- Dull semi-glossy texture
- Petiole ranges from 15–20 cm long
- Pinnae approximately 6–9 mm wide at the lowest pinna
- Rachis not too moderately spirally twisted
- Seedling pinnae are divided
- Pollen cones are spindle-shaped, 14–21 cm long and 4.5–5.5 cm in diameter
- Male cones typically range from 12–20 cm long and up to 5 cm in diameter
- Female cones range from 20–35 cm long, 8–12 cm wide, and up to 12 cm in diameter
- Female cones have green and pink sections on the sporophyll
- Number of cones is very irregular
- Male plants can have up to four cones that are curved
- Female plants have one to two ovoid cones
Red Sacrotesta Seeds, Irregular Prism Shape, Uniformly Spread Within the Cycad, Edible After Proper Preparation
Food Source, Ornamental
About Macrozamia heteromera
Macrozamia heteromera is a species of cycad belonging to the Zamiaceae family, endemic to the Australian state of New South Wales. First discovered by botanist Charles Moore in 1858, this cycad is typically found in dry sclerophyll woodlands, particularly within the Warrumbungle Mountains and the Coonabarabran district.
Botanical Characteristics
A defining feature of Macrozamia heteromera is its low-trunked growth habit, with stems usually remaining below one meter in height. The species is distinguished from others in the Macrozamia genus by its mid-green, narrow pinnae, which are often divided, a characteristic also observed in its seedling leaves. The leaves themselves can grow up to 90 cm long, supported by petioles of about 20 cm. Reproductive structures include spindle-shaped pollen cones ranging from 12-20 cm for males and larger ovoid female cones up to 35 cm in length.
Toxicity and Traditional Use
Like many cycads, Macrozamia heteromera possesses toxic seeds and leaves, containing the azoxyglycoside macrozamin. This toxicity acts as a defense mechanism against herbivores. Historically, Indigenous Australians utilized the seeds as a food source, employing methods of roasting and prolonged washing to neutralize the toxins, rendering them edible and starchy.
Discovery and Taxonomy
Charles Moore's initial discovery in 1858 was based on leaf specimens, with a more complete description following in 1883 after his assistant collected fruit. Early classifications included variants such as 'glauca' and 'tenuifolia', but a 1998 revision by David L. Jones recognized these as distinct species, Macrozamia glaucophylla and Macrozamia polymorpha, respectively, within the broader Macrozamia heteromera complex.
Source: Wikipedia ↗
Frequently Asked Questions
Where is Macrozamia heteromera found?
Macrozamia heteromera is endemic to New South Wales, Australia. It is primarily found in the north-western region of New South Wales, specifically in the Warrumbungle Mountains and extending further southwest towards the Coonabarabran district.
What are the distinctive botanical features of Macrozamia heteromera?
This cycad is distinguished by its mid-green, narrow leaves with pinnae that are usually divided. Seedling pinnae are also divided. It typically grows with a low trunk, usually below one meter in height.
Are the seeds and leaves of Macrozamia heteromera safe to eat?
No, the seeds and leaves of Macrozamia heteromera are toxic due to the presence of the azoxyglycoside macrozamin. However, Indigenous Australians developed methods of preparation, such as roasting and prolonged washing, to detoxify the seeds, making them edible.
What is the toxicity of Macrozamia heteromera?
Macrozamia heteromera produces the toxic azoxyglycoside macrozamin. This serves as an evolutionary defense mechanism against herbivores. Symptoms of poisoning in livestock, known as 'zamia staggers' or 'zamia wobbles', can include staggering and loss of hindquarter control.
How was Macrozamia heteromera discovered?
The species was first discovered by Australian botanist Charles Moore in 1858, who collected leaf specimens. However, a full description was not possible until 1882 when his assistant, Ernst Betche, collected adequate leaf and fruit specimens for Moore to formally name it.
What are the different variants of Macrozamia heteromera?
Charles Moore initially described two variants, glauca and tenuifolia. However, a revision in 1998 by David L. Jones recognized these as separate species: Macrozamia glaucophylla (formerly glauca) and Macrozamia polymorpha (formerly tenuifolia).
Related Cycad species
Encephalartos trispinosus
Encephalartos trispinosus is a species of cycad native to the Eastern Cape Province of South Africa. It features an upright stem and pinnate leaves that can range in color from gray-greenish to blue, with distinctive spiny leaflets. This dioecious species produces separate male and female cones, with seeds covered in a sarcotesta.
Encephalartos ghellinckii
Encephalartos ghellinckii, commonly known as the Drakensberg cycad, is an evergreen species endemic to South Africa, primarily found in the Natal Drakensberg region. It thrives in diverse habitats from foothills to high elevations, including stream banks, steep grassy slopes, and sandstone outcrops, demonstrating remarkable resistance to veldfires, snow, and frost. Distinctive features include its olive to yellow-green fronds, narrow leaflets with revolute margins, and lemon-colored, woolly cones.
Encephalartos cycadifolius
Encephalartos cycadifolius is a cycad species native to the Winterberg mountains in the Eastern Cape province of South Africa, found at high elevations. It is characterized by an underground trunk, pinnate leaves with entire margins, and distinct male and female cones. This species is dioecious, meaning it has separate male and female plants.