Fruit subglobose-ovoid or globose, slightly appressed, 2-2.5 by 1.75-2 mm, with a 0.25-1 mm long apical beak.
Africa: Seychelles (Seychelles present), Asia-Temperate: Oman (Oman present), Asia-Tropical: Borneo present ‒ absent; India present; Jawa (Jawa present); Lesser Sunda Is. present; Malaya (Peninsular Malaysia present); Maluku (Maluku present); New Guinea present; Philippines (Philippines present); Sri Lanka (Sri Lanka present); Sulawesi (Sulawesi present); Sumatera (Sumatera absent); Thailand (Thailand present), Indian Ocean and the western part of the Pacific present, Madagascar present, Persian Gulf present, Ryukyu Islands present, S Africa present, Tonga Islands present, along the southern coast of Asia present, the tropical coasts of Australia present
Halodule uninervis is widely distributed in the Indian Ocean and the western part of the Pacific. It is common along the coast of E Africa from the Red Sea as far as the province of Natal (S Africa), and it occurs also on Madagascar and the Seychelles It is probably common along the southern coast of Asia, where it has been found in Oman, the Persian Gulf, India and Sri Lanka. The eastern part of the area extends from the Ryukyu Islands, Indochina and Thailand through Malesia to the tropical coasts of Australia; in the Pacific it has been found at least as far eastward as the Tonga Islands. In Malesia it has been recorded from Peninsular Malaysia, Java, Borneo, Philippines, Celebes, Lesser Sunda Islands, Moluccas, and New Guinea. There are no records from Sumatra and Borneo, probably due to under-collecting.
The variability of the leaf width of the various populations is considerable and one can distinguish between wide-leaved and narrow-leaved populations which grow sympatric but never together. More detailed studies are necessary to establish whether these differences are only environmentally induced or whether they are genetically determined.
Hartog - in Blumea. 1964: f. 1-3
Meñez, Phillips & Calumpong - in Smithson. Contr. Mar. Sci. 1983: f. 9, 10 (map)
Merr. - in Philipp. J. Sc., Bot. 1915: 3
Backer - in Handb. Fl. Java. 1925: 51
Brouns - in Science in New Guinea. 1986: f. 3
Ostenf. - in Dansk. Bot. Ark. 1916: 30
Miki - in Bot. Mag. Tokyo. 1932: f. 8
Hartog - in Blumea. 1964: f. 4
Tomascik, Mah, Nontji & Moosa - in Ecology of the Indonesian seas. 1997: f. 18.11 (map), 18.24
Asch., Sea-grasses of the World. 1970: 147
Asch. - in Engl., Pflanzenr. 11. 1907: 152