The genus Halophila Thouars (Hydrocharitaceae).




Author:

L.M.A. du Petit-Thouars (1806) Genera Nova Madagascariensia 2

Species:

The genus Halophila is presently being revised by several workers, with species allocation therefore in a state of flux. Twelve species of Halophila are currently recognised, of which seven occur in Western Australia:

Life history:

Halophila species can be monoecious or dioecious, with flowers usually unisexual and solitary. The male flower is pedicellate, while the female is generally sessile or almost so. While these plants probably flower all year round in the tropics, flowering and fruiting is restricted to summer in temperate regions.

Distribution:

The genus Halophila is widely distributed throughout tropical waters, with some species extending into subtropical and temperate waters; several species are common around the coast of Australia. Although primarily marine, some species tolerate hypo- and hyper-saline conditions. Six species have been identified from Western Australia to date.

 

Halophila australis Doty & Stone
Doty, M.S. & Stone, B.C. (1966) Brittonia 18: 306, fig. 2

  

Distribution and ecology:

 

 

Halophila decipiens Ostenfeld
Ostenfeld, C. H. (1902) Bot. Tidsskr. 24:260, with fig.

  

Distribution and ecology:

Recorded as far south as the Abrolhos Islands (Walker & Prince, 1987).

 

Halophila minor (Zoll.) den Hartog
Hartog, C. den in Steenis, C.G.G.J. van (Ed) (1958), Flora Malesiana Series I 5: 410, fig. 17b

  

Distribution and ecology:

 

 

Halophila ovalis (R. Brown) Hooker, J.D.
Hooker, J.D. (1858) Flora Tasmaniae Vol. 2: 45

Halophila ovalis- click for a larger image (32.7 kb)

Distribution and ecology:

Widely distributed in coastal waters around Australia, Halophila ovalis is common in Western Australia in both tropical and temperate waters. Specimens have been collected from most locations suitable for seagrass growth.

 

Halophila ovata Gaudichaud in Freycinet
Gaudichaud-Beaupre, C. in Freycinet H.L.C. de S. de (1828) Voyage Autour du Monde ... sur les Corvettes de S.M. l'Uranie et al Physicienne. Botanique: 65 Voy. Bot. Pl. 40, f. 1

  

Note that this name may be illegal: see comments by M.-H.Sachet & F.R.Fosberg, Taxon 22 (1973) 441 (Ref. APNI: http://www.anbg.gov.au/cgi-bin/apni; accessed 22 Jan. 2003).

Distribution and ecology:

Recorded as far south as Shark Bay (Walker & Prince, 1987).

 

Halophila spinulosa (R. Brown) Ascherson
Ascherson, P.F.A. in Neumayer, H. (1875) Anleitung zu Wissenschaftlichen Beobachtungen auf Reisen: 368

  

Distribution and ecology:

Recorded as far south as Geraldton (Oakajee) (van Keulen et al., 1998), usually occurs in gaps amongst larger species, but has been observed to form small, dense stands in shallow sub-tidal areas.

 

Halophila tricostata Greenway
Greenway, M. (1979) Aquat. Bot. 7:68

  

Distribution and ecology:

A specimen of this species was recently collected from Bateman Bay, Ningaloo (Fitzpatrick et al., 2002), and represents the first record of this species outside Queensland. Found amongst Halophila minor on coral rubble and sand at the base of a coral bommie, at approximately 5m depth. Perviously found in north Queensland, on fine mud substrate or on coarse sand and shell fragments (Greenway, 1979; Kuo et al., 1993).


The Western Australian Seagrass Web pages were created and are maintained by:

Mike van Keulen
Murdoch University
Western Australia.
Last update: Tuesday, 25 October, 2005 10:14