Cycas micronesica
Forests·Arborescent·Insect (symbiotic relationship with Anatrachyntis moth species)·Endangered
Cycas micronesica is a medium-sized cycad species native to islands in Micronesia and the Mariana Islands. It is characterized by its straight, palm-like trunk and long, pinnate leaves. Historically a food source, its seeds contain a neurotoxin linked to a neurological disease, and the species is currently threatened by invasive pests.
Key Facts
- ›Native to Yap, Guam, Rota, and Palau.
- ›Seeds contain the neurotoxin BMAA, linked to Lytico-Bodig disease.
- ›Can grow up to 15 meters tall, with a trunk typically 2-5 meters.
- ›Leaves are long, with numerous pinnae.
- ›Dioecious, with separate male and female plants.
- ›Listed as Endangered by the IUCN due to invasive species.
Federico Nut, Fadang
Yap, Micronesia, Guam, Rota, Palau
Straight, palm-like trunk, Ringed with frond scars, Medium-sized, typically 2–5 meters tall, Can reach heights up to 15 meters
- 140–180 cm Long
- Flat In Section
- 130 -150 Pinnae Per Leaf
- Pinnae Are 240 – 280 mm Long, 16 –17 mm Wide, 0.35 - 0.45 mm Thick
- Glabrous, Dull Green Or Slightly Bluish-Green When Developing
- Become Glossy Mid-Green At Maturity
- Slightly Recurved Margins
- Strongly Discolorous
- Midrib Not Sharply Raised, Equally Prominent Above and Below
Flatten to ovoid, Green becoming orange, Not pruinose, 50–60 mm long, 45–50 mm in diameter, Sarcotesta 3–6 mm thick
Traditional Food Source
Invasive Species, Habitat Loss, Biomagnification of Bmaa In Flying Foxes
About Cycas micronesica
Cycas micronesica: A Threatened Island Cycad
Cycas micronesica, commonly known as federico nut or fadang in Chamorro, is a species of cycad native to several islands in the western Pacific, including Yap, Guam, Rota, and Palau. This medium-sized tree typically reaches heights of 2 to 5 meters but can grow significantly taller, up to 15 meters. It is distinguished by its straight, palm-like trunk, which is marked with scars from its fronds, and its long, pinnate leaves that can extend up to 1.8 meters.
Botanical Characteristics
The leaves of Cycas micronesica are a notable feature, characterized by their length and the abundance of pinnae (leaflets) they bear. Each leaf can have between 130 to 150 pinnae, which are flat in cross-section with slightly recurved margins. The midrib is not sharply raised, and the pinnae are a dull green when young, maturing to a glossy mid-green. As a cycad, Cycas micronesica is dioecious, meaning individual plants are either male or female. Female cones, or megasporophylls, are typically pale fawn to orange-brown and can be quite large, while male cones are smaller, bearing pollen on the underside of modified leaves.
Historical Significance and Toxicity
Historically, the seeds of Cycas micronesica served as a traditional food source on Guam until the 1960s. However, these seeds contain the neurotoxin BMAA (Β-Methylamino-L-alanine), which is produced by symbiotic cyanobacteria within the plant's specialized roots. Chronic dietary exposure to BMAA has been implicated as a cause of Lytico-Bodig disease, a neurological disorder similar to amyotrophic lateral sclerosis (ALS), which had a high incidence among the Chamorro people. The decline in the use of cycad flour and increased Americanization following World War II correlated with a decrease in the disease's prevalence.
Conservation Concerns
Cycas micronesica is currently facing severe threats, leading to its classification as Endangered by the IUCN Red List. The primary danger comes from invasive species, most notably the diaspidid scale Aulacaspis yasumatsui, which was introduced to Guam in 2003 and caused rapid mortality. Other invasive pests, including the cycad blue butterfly and longhorn beetles, further stress the population. Habitat loss due to human population growth and military activities also contributes to its decline. Efforts are underway to control these invasive species and protect the remaining populations of this ecologically and historically significant cycad.
Source: Wikipedia ↗
Frequently Asked Questions
What are the common names for Cycas micronesica?
Cycas micronesica is commonly known as federico nut or fadang in the Chamorro language. These names are used to refer to the species in its native regions.
Where is Cycas micronesica found naturally?
This cycad species is indigenous to the islands of Yap in Micronesia, the Mariana islands of Guam and Rota, and The Republic of Palau. Its natural range is confined to these Pacific island territories.
What are the characteristics of Cycas micronesica leaves?
The leaves of Cycas micronesica are quite long, typically measuring 140–180 cm. They are flat in section and bear a large number of pinnae, from 130 to 150, which are arranged along the rachis.
Is Cycas micronesica toxic?
Yes, the seeds of Cycas micronesica contain the neurotoxin BMAA. Chronic exposure to this toxin has been associated with a neurological condition known as amyotrophic lateral sclerosis/parkinsonism–dementia complex (ALS/PDC) among the Chamorro people of Guam.
What is the conservation status of Cycas micronesica?
Cycas micronesica is currently listed as Endangered by the IUCN Red List. This status is primarily due to severe threats from invasive species that have caused significant population declines.
How does Cycas micronesica reproduce?
Cycas micronesica is dioecious, meaning it has separate male and female plants. Female plants produce ovules on megasporophylls, while male plants bear microsporophylls with pollen sacks. Pollination can occur through a symbiotic relationship with certain moth species.
Related Cycad species
Zamia melanorrhachis
Zamia melanorrhachis is a species of cycad native to Colombia, found in forests at low to moderate altitudes. It is characterized by its subterranean stem and compound leaves with dark, prickly petioles and rachises. This dioecious plant produces distinct male and female cones, with the female cones being larger and wine-red to dark red-brown.
Zamia variegata
Zamia variegata is a species of cycad native to the forests of Belize, Guatemala, Honduras, and Mexico. This species belongs to the Zamiaceae family and is characterized by its habitat within forest ecosystems. Unfortunately, Zamia variegata faces significant threats from habitat destruction, which has led to a substantial decline in its population.
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