Alsomitra macrocarpa (Blume) M. Roem. (Cucurbitaceae) /Burung Sayap (Winged Bird )
Alsomitra is a climbing plant native to the tropical rainforests of Asia, particularly the Malay Peninsula. Belonging to the gourd family, the fruit of this plant is bell-shaped and about the size of a football. Suspended from the vine high in the forest canopy, each fruit is densely packed with approximately 300 winged seeds which fall from the underside of a fruit when it matures.
The transparent, papery wings allow the seeds to glide gracefully from the fruit. Seeds can travel 100m from the vine in calm conditions, or up to 1km with the help of wind.
Timun Jawa is a vine that grows on tropical trees. We can recognize this plant from its large fruit, and has winged seeds measuring 13 cm.
The seed wings even inspired scientists to build more stable model airplanes. This research was conducted by researchers from the University of Tokyo, since 39 years ago.
From its classification, it can be seen that the Javanese cucumber belongs to the Cucurbitales order and the Cucurbitaceae family. It is one of 34 Alsomitra species in the world.
Morphology and Characteristics of Alsomitra Macrocarpa
Alsomitra macrocarpa requires other plants to reproduce, from seedlings to adults. This plant looks woody and can grow up to 30 meters high.
In some areas, this one flora is even considered a pest because of its crown. If not controlled regularly, these plants can cover the entire surface of the host.
Uniquely, the growth of the Javanese cucumber follows the direction of the sun. It has a fruit the size of a soccer ball or coconut, with a diameter of up to 300 mm or around 30 cm.
The tip of the fruit looks open with seeds arranged in a row. It is these seeds that transform into seeds, their wings making the spread of plants unpredictable.
Alsomitra macrocarpa’s wings are yellowish-white. The surface is slightly transparent, and there is an oval hard layer and brown in the middle.
Habitat and Distribution of Alsomitra Macrocarpa
As already mentioned, the Javanese cucumber is spread across tropical Asia including Indonesia and Malaysia. It grows in low areas up to 700 meters above sea level.
In Indonesia, we can find this plant in Sumatra, Java, Bacan, Kalimantan and Sulawesi. They even spread to Halmahera, the Aru Islands, and Papua New Guinea.
One of the most popular Alsomitra macrocarpa collections is in the Bogor Botanical Gardens. In that area, this plant usually grows at an altitude of 300 meters above sea level.
It is undeniable, the winged shape of the seeds facilitates the distribution of Java cucumber. Thanks to its aerodynamic capabilities, the seeds can be carried even up to the top of the ship’s deck.
According to various sources, the speed at which Alsomitra macrocarpa’s wings descend is around 0.4 meters per second. Meanwhile, the flight speed of the signalman reaches 1 meter per second.
Use and Benefits of Alsomitra Macrocarpa
Alsomitra macrocarpa is not classified as a commercial plant. Even though it has a large fruit, this part is rarely consumed or used as a processed product.
Likewise with the leaves and stems. So far the only benefit of the plant is its seed wings, which inspired scientists to build airplane wings.
Referring to the research of Akira Azuma and Yoshinori Okuno, the shape of the Alsomitra macrocarpa’s wings is suitable for lowering the plane’s altitude. This became a reference in the development of world aviation.
But another researcher, JW Dunne also believes that the shape of the wing is relatively difficult to direct. It excels in pitch and roll technique, but is unstable in terms of navigation.
For information, at first experts categorized the Javanese cucumber into the genus Zanonia. But in 1843, this flora was then included in the genus Alsomitra by Blume.
Java Cucumber Species Taxonomy
Classifications and Characteristics
|Plant Growth Form||Climber, Vine & Liana|
|Lifespan (in Singapore)||Perennial|
|Native Distribution||Southern Thailand, Peninsular Malaysia, Borneo, Indonesia (Sumatra, West Java, Sulawesi, Moluccas (Aru Islands), Philippines, New Guinea (Papua New Guinea including Bismark Archipelago, West Papua)|
|Preferred Climate Zone||Tropical|
Description and Ethnobotany
|Growth Form||Large climber 30-50m long, base of the stem of mature specimens to 15cm thick.|
|Foliage||Mature leaves mid green, unlobed, ovate to elliptic, 8-16cm long by 3-13cm wide. Juvenile plants with a completely different form and leaf shape. Young plants creeping on forest floor with thin, thread like stem; leaves oblong, to 1cm long, spaced far apart. Juvenile plants adhering to tree trunks for support via adhesive discs on the tip of the bifid tendrils, leaves becoming hastate (spear shaped) in shape (also with auricles or ‘ear like’ lobes in younger leaves). Mature leaves are produced when the plant climbs up to 5m or more in height.|
|Flowers||Male and female inflorescence borne on separate shoots. Male inflorescence many flowered, 5-15cm long, arising from short leaf shoots, 1-2 times branched. Male flowers greenish-cream, 0.7-1cm in length. Female inflorescence usually unbranched, with 5(occasionally 10) flowers. Female flowers on long pedicels (flower stalks) to 20cm long; petals to 09=.9cm long.|
|Fruits||Mature fruit a brown wood capsule, 20-30cm across. Inside of the fruit with a soft spongy layer, packed with many seeds. Seeds pale brown 2.5cm long by 2-2.3cm wide, set in a large, membranous wing 10-12cm across.|
In forests to 800m, on rich soils and clayey soils along rivers.