Enhalus acoroides (L.f.) Royle

Last updated: 27 May 2015

Scientific Name

Enhalus acoroides (L.f.) Royle


Enhalus acoroides (L.f.) Royle, Enhalus koenigii Rich., Enhalus marinus Griff., Stratiotes acoroides L.f., Vallisneria sphaerocarpa Blanco [1]

Vernacular Name


Setul, jerangau laut [2]


Deringu laut (Indonesian); jela­mun (Javanese); lamun (Sundanese; Balinese) [2]


Eel grass, tropical eel grass [2]


Lamon (Tagalog; Bikol); mariu-bariu (Bikol); pallaipat­baibai (Ilokano) [2]

Geographical Distributions

Enhalus aco­roides is a marine plant distributed from East Africa, Madagascar and the Seychelles through the tropical parts of the Indian Ocean, the south­ern part of the Red Sea, and throughout Southeast Asian coastal waters to China, Northern Aus­tralia, Micronesia and Melanesia. It is rare in the Indian Ocean area, but very common in Southeast Asia, where it occurs around Thailand, Cam­bodia, Vietnam, Malaysia, Indonesia, Papua New Guinea and the Philippines.[2]

E. aco­roidesis found along sheltered or exposed shallow sea coasts, from around the low ­water mark to about 5 m depth. It occurs in a wide range of habitats and thrives in small depressions on tidal flats between the levels of mean low water and low water at spring tide. E. acoroides may oc­cur patchily or form a closed monospecific stand, the latter particularly on sandy and muddy bot­toms, often mixed with coarser materials. It may grow abundantly in fish ponds, waterways and coastal resorts, and can form an obstruction. [2]

Botanical Description

E. aco­roidescomes from the Hydrocharitaceae family. It is a perennial, marine, submerged, dioecious, rhizomatous, coarse and hairless herb. [2]

There are usually 2-6 leaves which are sessile, arranged distichously at the end of the rhizome and enclosed by a flattened, transparent sheath about 15 cm long and often twist­ed and damaged. The blade is rib­bon-like, measuring 30-150 cm x 1-1.8 cm, with sheathed base, thickened by coarse margin, with very tough vascular bundles which become black after the blade de­cays and remain attached to the rhizome. The apex is rounded or obtuse, and with 13-19 veins. It runs longitu­dinally parallel, with 30-40 air channels and parallel to the veins. It is visible outside as a fine striping with ir­regularly spaced septations. [2]

The male inflorescence is an axillary, spathe peduncled consists of 2 connate bracts. The margin of the outer one embraces the inner one. The peduncle is 5-10 cm long and cylindrical. The bracts are ovate-Iance-shaped, measuring 5 cm x 3 cm, faintly keeled and rough long-haired on the keel. [2]

The flowers are small, nu­merous, with stalk on a central stipe and caducous just before anthesis while the mature buds rise to the level of the water. The pedicel is 3-12 mm long, un­equal and very thin. There are 3 sepals which are oblong, measure 2 mm long re­flexed and white. There are 3 petals which are ovate, and wider but slightly shorter than sepals. They are white. There are 3 erect stamens which are 1.5-1.8 mm long, with subsessile anthers, 2-locular, with spherical pollen grains and measure about 175 µm in diameter. The female inflorescence is a stalked spathe consists of 2 nearly free bracts where one embraces the other with both margins, per­sistent in fruit and enclosing 1 flower. The stalk (pedicel) is 40-50 cm long and spirally contracted after fertiliza­tion. The bracts are oblong-Ianceo­late, measuring 4-6 cm x 1-2 cm and strongly keeled. The keel and veins are rough long-haired. The 3 sepals are oblong and reddish. There are 3 petals which are oblong-linear, measuring 4-5 cm x 0.3-0.4 cm, white, with waxy surface and papillose. [2]

The ovary is rostrate, measuring 5 cm x 0.5 cm, densely set with long fringe-like hairs, composed of 6 carpels, 1-locular and with numerous ovules. There are 6 very short styles. There are 6 stigmas where each forks from the base. They are 10-12 mm long and densely cov­ered with linear papillae. [2]

The 8-14 seed­ed fruit is berry-like, ovoid to nearly spherical, measures 5-7 cm in diametre, length­wise ribbed, densely hairy, green, brown or black and open­s irregularly at the apex at its maturity. [2]

The seed is brown, angular-obconoidal, measuring 1-1.5 cm x 1.2 cm. [2]

It is a creeping rhizome, measures up to 1.5 cm in diametre, with wide and septate air channels inside, while at the outside, it bears numerous simple and cord-like roots, measuring 10-20 cm x 0.3-0.5 cm and densely clothed with persistent fi­brous strands of decayed leaves. [2]


No documentation.

Chemical Constituent

No documentation.

Plant Part Used

No documentation.

Traditional Use

No documentation.

Preclinical Data

No documentation.

Clinical Data

No documentation.


No documentation.

Poisonous Management

No documentation.

Line drawing


Figure 1: The line drawing of E. acoroides (L.f.) Royle [2]


  1. The Plant List. Ver1.1 Enhalus acoroides (L.f.) Royle. [homepage on the Internet]. c2013 [updated 2012 Mar 23; cited 2015 May 29] Available from: http://www.theplantlist.org/tpl1.1/record/kew-309482
  2. Enhalus acoroides (L.f.) Royle. In: Brink M, Escobin RP, editors. Plant Resources of South-East Asia No. 17: Fibre Plants. Leiden, Netherlands: Backhuys Publishers; 2003.