Macrozamia heteromera

Last updated

Macrozamia heteromera
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Gymnospermae
Division: Cycadophyta
Class: Cycadopsida
Order: Cycadales
Family: Zamiaceae
Genus: Macrozamia
Species:
M. heteromera
Binomial name
Macrozamia heteromera
C.Moore
Macrozamia heteromera Dist Map12.png
Occurrence data from AVH
Leaf specimen of M. heteromera EB1911 Gymnosperms - Macrozamia heteromera.jpg
Leaf specimen of M. heteromera

Macrozamia heteromera is a species of cycad in the family Zamiaceae initially discovered by Charles Moore in 1858 and is endemic to New South Wales, Australia. [1] It can be found in the north-western region of New South Wales within the Warrumbungle mountains and further south west towards the Coonabarabran district. It is a low trunked cycad usually at a height below 1 metre and can be found in dry sclerophyll woodlands. M. heteromera can be distinguished from the rest of the Macrozamia genus by its mid-green, narrow, usually divided pinnae and divided seedling pinnae. [2] It is a plant that has toxic seeds and leaves, a characteristic common to cycads. However, after proper preparation and procedure, the seeds are fine for consumption.

Contents

Discovery

Macrozamia heteromera was first discovered by Australian botanist Charles Moore during a journey in 1858 where he discovered leaf specimens of the Heteromera. [3] However, as Moore was unable to collect any of the fruit, he did not have enough information to provide a thorough description of the plant. [3] It was not until the year 1882 where Moore’s assistant Ernst Betche had collected adequate specimens of the leaves and fruit of the Heteromera which upon receiving was named by Moore. [3] He described the plant as having a small trunk approximately 6–8 in (15–20 cm) long and covered with what seemed to be a red coloured wool. [3] Furthermore, its leaves were 2 ft (0.61 m) long, covered in long hairs and spirally twisted consisting of pinnae forked variously and simply around 6 in (15 cm) long. [3] At the time, Moore had believed that there were two other variations of M. heteromera. [3] He named the two variants glauca and tenuifolia. [3] The glauca was distinguishable by its longer leaves that lacked rigidity and were always glaucous and glabrous. [3] The tenuifolia’s leaves were more rigid of a dark green colour. [3] Furthermore, its pinnae forked twice and were bright red at the base. [3] However, after a small revision in 1998 by David L Jones, the glauca and tenuifolia variants became recognised as their own species under the M. heteromera complex. [2] The glauca variant became known as Macrozamia glaucophylla and the tenuifolia became Macrozamia polymorpha . [2]

Taxonomy and nomenclature

M. heteromera was first described in 1883 by Charles Moore. This was done in the 17th volume of the Journal and Proceedings of the Royal Society of New South Wales where he described ten plants that were classified under the Macrozamia genus. Moore had named it M. heteromera after its divided pinnae that were very inconsistent in appearance. [4]

M. heteromera is one of three species originally recognised under the Zamiaceae family before David L Jones revised the M. heteromera complex in 1998. [2] The M. heteromera complex known for their divided pinnae includes Macrozamia heteromera, Macrozamia diplomera and Macrozamia stenomera . These cycads can be found close to each other, are often mistaken for one another and secluded from any other cycad. [5] This may suggest a casual correlation that plants with divided pinnae possess a slight selective advantage in their environment. [5]

Description

The Macrozamia Heteromera is a small low-trunked cycad that often grows to a height of less than 1 meter [3] . The stem grows up from 15–25 cm (5.9–9.8 in) in diameter and is light green in colour. It supports a crown consisting of two to eight leaves. The moderately keeled leaves can grow to around 50–90 cm (20–35 in) long and are composed of up to 60 to 100 pinnae of a dull semi-glossy mid-green colour that branches into two (i.e. the pinnules are once or twice dichotomous) which is a feature that helps to distinguish this from other species within the Macrozamia genus. [2] The Petiole ranges from 15–20 cm (5.9–7.9 in) and 6–9 millimetres (0.24–0.35 in) wide at the lowest pinna. The Rachis is not too moderately spirally twisted. Pollen cones are spindle shaped, 14–21 centimetres (5.5–8.3 in) long and 4.5–5.5 centimetres (1.8–2.2 in) in diameter along with a microsporophyll lamina that is approximately 16–21 millimetres (0.63–0.83 in) long and 12–19 millimetres (0.47–0.75 in) wide. The number of cones is very irregular, a feature of the Macrozamia species. However, on average, male plants can have up to four cones that are curved, and females have one to two of an ovoid shape. [4] Male cones typically range from 12–20 cm (4.7–7.9 in) long and up to 5 cm (2.0 in) in diameter. Similarly, females range from 20–35 centimetres (7.9–13.8 in) long, 8–12 centimetres (3.1–4.7 in) wide are up to 12 centimetres (4.7 in) in diameter and have green and pink sections on the sporophyll. [4] Inside the cones are red sacrotesta seeds of an irregular prism shape that is uniformly spread in the cycad. [2]

Distribution and habitat

Occurring on sandy, stony and infertile siliceous soils over acid volcanics and often in dry sclerophyll woodlands, Macrozamia Heteromera is an endemic species to New South Wales. [2] It can be found in north-western New South Wales in the Warrumbungle Mountains and further south west towards the Coonabarabran district. [2]

The Warrumbungle mountain range is composed of complex rocky formations, the remnants of a large heavily eroded shield volcano active from 13 to 17 million years ago. [6] The climate of Warrumbungle is temperate and warm with a significant frequency of rainfall all year round including the driest seasons. The average annual temperature and precipitation of the range is 17.1 °C and 655mm respectively. [7] The climate of Warrumbungle is classified as Cfa (Humid subtropical) with warm and wet climates according to Köppen-Geiger. [7]

Coonabarabran is a small town known as the 'Gateway to the Warrumbungles'. [8] It is at an elevation of 509m above sea level with a minimum and maximum temperature of -3.6 °C and 35.9 °C, averaging once per week in winter and summer respectively. [9] Coonabarabran has an average rainfall of 744.7mm annually, the seasonal rainfall pattern can be described as follows: Summer (32%), Autumn (23%), Winter (23%) and Spring (23%). [10] [11]

Toxicity

Cycads of the Zamiaceae family are generally toxic and produce the azoxyglycoside macrozamin. [5] [12] Macrozamin is composed of a primeverosa which is a disaccharide formed by glucose and xylose. [12]

Ecology

The seeds from this cycad are edible after proper preparation. The macrozamin produced by M. heteromera is the result of an evolutionary defence mechanism to prevent itself from being consumed by herbivores. [12] This allows M. heteromera to safely grow and reproduce without interference from predators (herbivores). [12] These predators could include caterpillars, cow and sheep. The Indigenous Australians utilised the cycad's seeds as a source of food. [5] They were able to remove the harmful toxins through roasting the seed and prolonged washing, resulting in an edible starchy endosperm. [5] The first reported poisoning from this cycad is believed to have occurred in 1916 within the Coonabarabran district. [13] Some fatalities of cattle had been reported and those affected had staggered and lost control of their hindquarters. [13] Only the leaves of M. heteromera were present within the paddock at the time which was reasonable enough evidence for them to believe it had been M. heteromera. [13] It was previously believed that M. heteromera had caused a mass sheep poisoning in the Coonabarabran district in 1929 where sheep had eaten the seeds of the cycad for an hour unmonitored. [14] This resulted in five sheep dying within 18 to 20 hours after consumption and death continuing for three weeks resulting in 2,200 sheep dying out of the total 6,000. [14] However, it was later confirmed that the poisoning was instead caused by Macrozamia diplomera via a veterinary report. [15] Farmers have used terms such as ‘zamia staggers’, ‘zamia rickets’ or ‘zamia wobbles’ to describe the symptoms due to cattle consuming Macrozamia seeds and leaves. [16] Farmers had coined the term ‘sheep nuts’ for M. heteromera seeds in particular. [16]

Related Research Articles

<span class="mw-page-title-main">Cycad</span> Division of naked seeded dioecious plants

Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly and live very long. Because of their superficial resemblance, they are sometimes mistaken for palms or ferns, but they are not closely related to either group.

<i>Zamia pumila</i> Species of cycad

Zamia pumila, commonly known as guáyara in Spanish, is a small, tough, woody cycad native to the Greater Antilles. Z. pumila was the first species described for the genus and, therefore, is the type species for the genus Zamia and the family Zamiaceae.

<span class="mw-page-title-main">Zamiaceae</span> Family of cycads

The Zamiaceae are a family of cycads that are superficially palm or fern-like. They are divided into two subfamilies with eight genera and about 150 species in the tropical and subtropical regions of Africa, Australia and North and South America.

<i>Macrozamia</i> Genus of cycads in the family Zamiaceae

Macrozamia is a genus of around forty species of cycads, family Zamiaceae, all of which are endemic to Australia. Many parts of the plant have been utilised for food and material, most of which is toxic if not processed correctly.

<i>Macrozamia moorei</i> Species of cycad

Macrozamia moorei is a cycad in the family Zamiaceae, native to Queensland (Australia).

<i>Lepidozamia peroffskyana</i> Species of cycad

Lepidozamia peroffskyana is a palm-like cycad in the family Zamiaceae. It is endemic to eastern Australia. The species is named after Count Peroffsky (1794-1857), benefactor of the St. Petersburg Botanical Garden.

<i>Macrozamia concinna</i> Species of cycad

Macrozamia concinna is a part of the plant family, Zamiaceae. It originates from a division of Cycadophyta which encompasses the complete species of cycads. M. concinna is primarily habituated in New South Wales, Australia and maintains a distinct appearance allowing it to be easily identifiable from other cycads. M. concinna also implements a unique method of reproduction to fertilise its offsprings, as opposed to the common method of wind pollination. This difference in reproduction mechanisms has survived throughout the ages of prehistoric cycad species and M. concinna continues to procreate with it.

<i>Macrozamia dyeri</i> Species of cycad

Macrozamia dyeri, known as djeeri, is a species of plant in the family Zamiaceae. It is endemic to Western Australia, occurring near Esperance. The seeds are consumable when prepared correctly and were an important resource to people of the region, but the plant is otherwise toxic to many species.

<i>Macrozamia glaucophylla</i> Species of plant

Macrozamia glaucophylla is a species of cycad from the genus Macrozamia and the family Zamiaceae. Endemic to New South Wales, Australia, this species has features that resembles palms, although both species are taxonomically quite different. The current population trend of Macrozamia glaucophylla is stable with 2,500 to 10,000 mature individuals. The species are found in several habitats including forest and savanna. Ecologically, Macrozamia glaucophylla lives in terrestrial system, a land-based community of organisms where the biotic and abiotic components interact in the given area.

<i>Macrozamia miquelii</i> Species of cycad

Macrozamia miquelii, is a species of cycad in the plant family Zamiaceae. It is endemic to Queensland and New South Wales in Eastern Australia. Located within sclerophyll forests dominated by eucalyptus trees, the cycad grows on nutrient-poor soils. It is recognised within the Zamiaceae family for its, medium height at 1 m, intermediate size of male and female cones and lighter green leaves compared to other cycads within the plant family of Zamiaceae. The seeds have an orange red sarcotesta which attracts fauna consumption, allowing a mutualistic seed dispersal for the cycad. These seeds are also edible for human consumption if prepared correctly to remove the toxins.

<i>Macrozamia mountperriensis</i> Species of cycad

Macrozamia mountperriensis is a species of plant in the family Zamiaceae endemic to the area around Mount Perry in Queensland; however, it is not considered threatened due to its large population in the area. The species was discovered by colonial botanists including Frederick Manson Bailey and James Keys in the late 1800s. All members of the Zamiaceae family are considered to be poisonous.

<i>Macrozamia riedlei</i> Species of cycad

Macrozamia riedlei, commonly known as a zamia or zamia palm, is a species of cycad in the plant family Zamiaceae. It is endemic to southwest Australia and often occurs in jarrah forests. It may only attain a height of half a metre or form an above trunk up to two metres with long arching fronds of a similar length. The giant cones amidst the crown of palm-like fronds contain edible seeds surrounded by red sarcotesta. The seeds are consumed by birds and animals, and can be a favoured part of the human diet when prepared correctly. M. riedlei benefits from a close association with bacteria that fix nitrogen, which also produce substances found throughout the plant that are toxic to some animals when consumed. The species is cultivated for ornamental use in urban and domestic environments.

<i>Macrozamia spiralis</i> Species of cycad

Macrozamia spiralis is a species of cycad in the family Zamiaceae. It is endemic to New South Wales in eastern Australia, where it is found in sclerophyll forest on low-nutrient soils. Plants generally lack a trunk and have 2–12 leaves that range up to 100 cm (40 in) in length.

<i>Zamia fischeri</i> Species of cycad

Zamia fischeri is a species of cycad in the family Zamiaceae. It is endemic to Mexico. It is often confused with Zamia vazquezii. Zamia fischeri is named after Gustav Fischer, a cycad enthusiast of the nineteenth century.

<i>Zamia pseudoparasitica</i> Species of cycad

Zamia pseudoparasitica is a species of plant in the family Zamiaceae. It is endemic to Panama.

<i>Zamia pygmaea</i> Species of plant in the family Zamiaceae

Zamia pygmaea is a species of plant in the family Zamiaceae found only in Cuba. It is the smallest living cycad. It is listed as critically endangered on the IUCN Red List based on its limited distribution, severely fragmented habitat, and population of less than 250 mature individuals.

<i>Encephalartos ferox</i> Species of cycad

Encephalartos ferox, a member of the family Zamiaceae, is a small cycad with 35 cm wide subterranean trunk. It gets its name from the Latin word ferocious, likely from the spine-tipped lobes on the leaves of the plant. It is found naturally on the south-eastern coast of Africa where it has been used by local people for its starch content. It is considered to be one of the most popular cultivated cycads.

<i>Encephalartos kisambo</i> Species of plant in the family Zamiaceae

Encephalartos kisambo is a species of cycad in the family Zamiaceae. It is native to Kenya and Tanzania. It is known as the Voi cycad.

<i>Zamia integrifolia</i> Species of cycad

Zamia integrifolia, also known as coontie palm, is a small, tough, woody cycad native to the southeastern United States, the Bahamas, Cuba, and the Cayman Islands.

References

  1. 1 2 Forster, P. (2010). "Macrozamia heteromera". IUCN Red List of Threatened Species . 2010: e.T42007A10619620. doi: 10.2305/IUCN.UK.2010-3.RLTS.T42007A10619620.en . Retrieved 16 November 2021.
  2. 1 2 3 4 5 6 7 8 Jones, David (1998). Flora of Australia. Vol. 48. Canberra: Australian Government Pub. Service. pp. 658–659.
  3. 1 2 3 4 5 6 7 8 9 10 11 Moore, Charles (1883). "Notes on the Genus Macrozamia". Journal and Proceedings of the Royal Society of New South Wales. Macquarie Centre Soc. 17: 115–122. doi: 10.5962/p.358950 . S2CID   259715748 – via Biodiversity Library.
  4. 1 2 3 Norstog, Knut; Nicholls, Trevor J. (15 May 2019). The Biology of the Cycads. Cornell University Press. doi:10.7591/9781501737329. ISBN   978-1-5017-3732-9.
  5. 1 2 3 4 5 Johnson, L.A.S. (29 July 1959). "The Families of Cycads and the Zamiaceae of Australia". Proceedings of the Linnean Society of New South Wales. 84 (389): 64–117.
  6. ↑ Johnson, David, May 11- (2009). The geology of Australia (2nd ed.). Cambridge: Cambridge University Press. ISBN   978-1-4619-3828-6. OCLC   856017224.{{cite book}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link)
  7. 1 2 "Climate Warrumbungle National Park: Temperature, climate graph, Climate table for Warrumbungle National Park". Climate-Data.org. Retrieved 26 May 2021.
  8. ↑ "Coonabarabran, NSW". Aussie Towns. Retrieved 30 May 2021.
  9. ↑ "Coonabarabran climate, averages and extreme weather records - www.farmonlineweather.com.au". www.farmonlineweather.com.au. Retrieved 30 May 2021.
  10. ↑ "Coonabarabran (Showgrounds) Monthly climate statistics". Climate statistics for Australian locations. Bureau of Meteorology, Australian Government. 27 May 2021. Retrieved 30 May 2021.
  11. ↑ "Macrozamia heteromera". Palm & Cycad Societies of Australia. Retrieved 26 May 2021.
  12. 1 2 3 4 Castillo-Guevara, Citlalli; Rico-Gray, Victor (2007). "The Role of Macrozamin and Cycasin in Cycads (Cycadales) as Antiherbivore Defenses". Journal of the Torrey Botanical Society. 130 (3): 206. doi:10.2307/3557555. ISSN   1095-5674. JSTOR   3557555.
  13. 1 2 3 Whiting, Marjorie Grant (1963). "Toxicity of cycads". Economic Botany. 17 (4): 270–302. doi:10.1007/BF02860136. ISSN   0013-0001. S2CID   31799259.
  14. 1 2 Hall, J. A.; Walter, G. H. (1 August 2014). "Relative Seed and Fruit Toxicity of the Australian Cycads Macrozamia miquelii and Cycas ophiolitica: Further Evidence for a Megafaunal Seed Dispersal Syndrome in Cycads, and Its Possible Antiquity". Journal of Chemical Ecology. 40 (8): 860–868. doi:10.1007/s10886-014-0490-5. ISSN   1573-1561. PMID   25172315. S2CID   211490.
  15. ↑ New South Wales Ministry of Agriculture. Agricultural gazette of New South Wales. OCLC   780069290.
  16. 1 2 Asmussen, Brit (2012). "Aboriginal vernacular names of Australian cycads of Macrozamia, Bowenia and Lepidozamia spp.: a response to "Cycads in the vernacular: a compendium of local names"". Australian Aboriginal Studies (2): 54–71 1. ISSN   0729-4352.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.