Hydrolea zeylanica (L.) Vahl

Hydrolea zeylanica (L.) Vahl





Vernacular Names


Gagabusan, sembung ku-uk (Sundanese), gunda (Javanese).

Thailand Po phee (Buri Ram).

Th[ur]y l[eej].

Geographical Distributions

H. zeylanica is widely distributed in eastern Africa, Pakistan, Nepal, India, Sri Lanka, Burma (Myanmar), Vietnam, southern China, Taiwan, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, the Philippines, Sulawesi and northern Australia.


H. zeylanica is a perennial herb and often much branched. Its stem is up to 150 cm long. It is creeping and freely rooting in the lower part and with many erect branches.

The leaves are arranged alternately, simple and entire, narrowly lance-shaped, sometimes oblong or elliptical, measuring 1.5-12 cm x 1-2.5 cm, wedge-shaped at base, acute at apex, hairless or slightly hairy and pinnately veined. The petiole is 2-5 mm long. The stipules are absent.

The inflorescence is an axillary raceme or panicle, or flowers solitary. The flowers are bisexual, regular and with 5-merous. The pedicel is 2-10 mm long. The sepal is partite near to the base, 5-7 mm long, usually glandular hairy and persistent. The petal is deeply partite, with whitish tube and lilac-blue segments which are white at base. It is 5-8 mm long. The stamens are free, which are inserted in the petal throat and alternate with the petal lobes. The ovary is superior, 2-celled, with 2 styles, widely divergent and with club-shaped stigmas.

The 4-5 mm long fruit is an ellipsoid capsule, bursting irregularly and many-seeded. The seeds are very small, oblong, longitudinally ribbed and with transverse ridges.

Ecology / Cultivation

H. zeylanica occurs in permanently or periodically swampy or inundated localities, often in rice fields, also in shallow pools and on river banks, up to 1000 m altitude. It often occurs gregariously, but is a weed of minor importance in the Malaysian region.

Line Drawing / Photograph



  1. Plant Resources of South-East Asia No.12(3): Medicinal and poisonous plants 3.