%IMAGEGALLERY{ "%BASEWEB%.%BASETOPIC%" exclude="arrow|igp_.*" sort="name" warn="0"}%

Excoecaria agallocha

DSC 0442.JPG
Three-lobed fruit of Excoecaria agallocha, Cairns, QLD Photo: F.Zich © CSIRO

DSC 0645.JPG
Inflorescence on male tree of Excoecaria agallocha, Cairns, QLD Photo: F.Zich © CSIRO

Common Names

Milky Mangrove ( [1])

Family

Euphorbiaceae

Name Reference

Excoecaria agallocha L.

Origin of Name

Ex-caecare’ means to make blind (in Latin), and refers to the toxic white sap or latex of this genus. ‘Agallocha’ means soft resinous wood (in Greek), and may refer to the resemblence of this species to Aquilaria malaccensis (= A. agallocha) commonly used in the production of incense in Asia ( [1]).

Summary

Species feature - Leaves with exuding white sap ( [1]).

Description

Tree or shrub growing 15 m high, sometimes deciduous in dry seasons. No above ground roots, but can sometimes have spreading surface roots.

DSC 0481.JPG
Foliage and fruit of Excoecaria agallocha, Cairns, QLD Photo: F.Zich © CSIRO

Leaves opposite, simple, ovate-elliptic to obovate in shape, 6-10 cm long, 3-6 cm wide, apex rounded to slightly emaginate. Edges may be slightly toothed. Exudes milky-white sap when broken.

Inflorescences are 3-11 cm long catkins, differing in male and female trees. Fruit is a 3-lobed capsule, becoming brown and releasing 3 seeds ( [2], [3]).

Botanical Description

GROWTH FORM & FOLIAGE

Shrub or tree to 7 m, occasionally to 15 m, shrubby or columnar, often multistemmed, dioecious, sometimes deciduous in dry season; bark grey, smooth, vertically fissured, pustular in larger trees; stem simple to slightly flanged buttresses; roots serpentine at surface, knotted, lenticellate.

FOLIAGE

Leaves opposite, simple, ovate to elliptic, green above and below, upper surface slightly shiny, 6.5-10.5 cm L, 3.5-5.2 cm W, margin serrate but variably conspicuous to entire, apex acuminate to rounded, base cuneate, margin serrate to entire, somewhat fleshy with abundant exuding milky-white sap when broken; basal blade glands 2(-4) on each side of petiole insertion; petiole terete 1.0-3.0 cm L, pale yellowish-green; stipules minute.

REPRODUCTIVE PARTS

Inflorescence axillary, 3-7 cm L, catkins within leaf-bearing part of shoot, differ in male and female trees; male inflorescence to 11 cm L, diffuse, series of spirally arranged, often glandular bracts, each subtend a flower; calyx lobes 3, narrow laciniate; sepals narrowly ovate, 1 mm L, 0.5 mm W; stamens 3, yellow, anthers 1 mm L, pistillode absent, filament 2 mm L; glands between stamens and inflorescence axis subglobular, sessile, 0.5 mm L; female inflorescence to 3 cm L; pedicel to 5 mm L, bracts glandular, basal bracteoles 2;calyx lobes 3, somewhat cupulate; staminodes absent; ovary tri-locular; styles 3, short, simple, stigma lobes 3 mm L; fruit 3-lobed capsule, 1.4 cm W, becoming brown and dehiscing to release 3 seeds; pericarp somewhat but not fleshy;

DISPERSAL PROPAGULE

Seeds spherical, pepper-corn like, dark brown, streaked, 5 mm W, endosperm absent, buoyant, germination epigeal; cotyledons somewhat cuneiform.

( [1] as Excoecaria agallocha var. agallocha).

Distribution

Distributed from East Africa through Asia, to Australia. In Australia, the variety is found from Melville Island, Northern Territory (11° 30’ S, 130° 51’ E) in the west, along the Queensland coast, to the Manning River, New South Wales (31° 53' S, 152° 41’ E) in the east ( [1]).

Localities (not complete):

Habitat

Commonly located at the landward zone and in sandy swales influenced by freshwater.

High-mid intertidal, downstream to upstream estuarine position ( [1]).

Biology

In Australia, flowering peaks in December, and propagule maturation occurs during January and February ( [1]).

Ethnobotany

In the Northern Territory, the sap of both varieties is used as a toxicant being applied as a fish poison and poisonous coating on spearheads. Leaves are used to treat epilepsy in Indonesia and Fiji ( [1]).

Biological Interactions  
Group Taxon
  41 taxa
Vascular Plants Acanthus ilicifolius
Vascular Plants Acrostichum speciosum
Vascular Plants Aegialitis annulata
Vascular Plants Aegiceras corniculatum
Vascular Plants Avicennia marina
Vascular Plants Barringtonia spp.
Vascular Plants Bruguiera exaristata
Vascular Plants Bruguiera gymnorhiza
Vascular Plants Bruguiera parviflora
Vascular Plants Bruguiera_sexangula
Vascular Plants Camptostemon schultzii
Vascular Plants Ceriops australis
Vascular Plants Ceriops tagal
Vascular Plants Ceriops pseudodecandra
Vascular Plants Cynometra iripa
Vascular Plants Diospyros geminata
Vascular Plants Heritiera littoralis
Vascular Plants Hibiscus tiliaceus
Vascular Plants Lumnitzera littorea
Vascular Plants Lumnitzera_racemosa
Vascular Plants Nypa fruticans
Vascular Plants Osbornia octodonta
Vascular Plants Rhizophora_apiculata
Vascular Plants Rhizophora X lamarckii
Vascular Plants Rhizophora mucronata
Vascular Plants Rhizophora stylosa
Vascular Plants Scyphiphora hydrophylacea
Vascular Plants Sonneratia alba
Vascular Plants Sonneratia caseolaris
Vascular Plants Sporobolus_virginicus
Vascular Plants Tecticornia halocnemoides
Vascular Plants Xylocarpus granatum
Vascular Plants Xylocarpus moluccensis
Mosses Macromitrium aurescens
Liverworts Acrolejeunea aulacophora
Liverworts Cheilolejeunea_intertexta
Liverworts Cololejeunea lanciloba
Liverworts Frullania ericoides
Liverworts Frullania subtropica
Liverworts Lejeunea flava
Liverworts Leptolejeunea maculata

Similar Species

E. agallocha is reportedly distinguished from E. ovalis by its serrate leaf margins, acute leaf apices and longer petioles - however, these characters are not discrete ( [1]).

QLD Poisons Information Centre: http://www.health.qld.gov.au/poisonsinformationcentre/plants_fungi/milkymangrove.asp

Australian Tropical Rainforest Plants: http://keys.trin.org.au/key-server/data/0e0f0504-0103-430d-8004-060d07080d04/media/Html/taxon/Excoecaria_agallocha.htm

PlantNET: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Excoecaria~agallocha

FloraBase: http://florabase.dec.wa.gov.au/browse/profile/10886

Wild Singapore: http://www.wildsingapore.com/wildfacts/plants/mangrove/excoecaria/excoecaria.htm

Guide to the Mangroves of Singapore: http://mangrove.nus.edu.sg/guidebooks/text/1060.htm

Encyclopedia of Life: http://www.eol.org/pages/1143602

DSC 0500.JPG
Stems, leaves and fruit of Excoecaria agallocha, Cairns, QLD Photo: F.Zich © CSIRO

Exocecaria agallocha fruit.jpg
Excoecaria agallocha fruit, Singapore. Photo: John Yong

DSC 0435.JPG
Bark of Excoecaria agallocha var. agallocha, Cairns, QLD Photo: F.Zich © CSIRO
-- NormDuke and EmmaClifton - 2012-12-21 - 12:28

References

  1. Duke, N. (2011). Mangroves of Australia. Manuscript. Vers.: 27 Sept 2011. (more)
  2. Lovelock, C. (1993). Field Guide to the Mangroves of Queensland. Australian Institute of Marine Science, Townsville, Qld. Available online: http://www.aims.gov.au/c/document_library/get_file?uuid=c9dcfc2e-6018-4302-8818-5ab3fe01f91f&groupId=30301 (more)
  3. Duke, N.C. (2006). Australia's Mangroves. The authoritative guide to Australia's mangrove plants. University of Queensland, Brisbane. (more)
  4. West, R.J., Thorogood, C.A., Walford, T.R. and Williams, R. J. (1984). Mangrove distribution in New South Wales. Wetlands (Australia) 4: 2–6. Available online: http://ojs.library.unsw.edu.au/index.php/wetlands/article/viewFile/128/141 (more)
  5. Bunt, J.S. (1982b). Mangrove Transect Data from Northern Queensland. Coastal Studies Series, Australian Institute of Marine Science AIMS-CS-82-1. Australian Institute of Marine Science. 41 p. Available online: http://data.aims.gov.au/extpubs/attachmentDownload?docID=2326 (more)
  6. Smith III, T.J. (1987). Seed predation in relation to tree dominance and distribution in mangrove forests. Ecology 68(2): 266-73. Available online: http://www.jstor.org/stable/pdfplus/1939257.pdf (more)
  7. Bunt, J.S. (1997). The Mangrove Floral and Vegetational Diversity of Hinchinbrook Island and the Adjacent Coast. Australian Institute of Marine Science, Townsville. Available online: http://data.aims.gov.au/extpubs/attachmentDownload?docID=3018 (more)
  8. Semeniuk, V. (1980). Mangrove zonation along an eroding coastline in King Sound, north-western Australia. Journal of Ecology 68: 789-812. Available online: (more)
  9. Boto, K.G., Bunt, J.S. and Wellington, J.T. (1984). Variations in mangrove forest productivity in northern Australia and Papua New Guinea. Estuarine Coastal and Shelf Science 19(3): 321-329. Available online: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDV-4DV0KPV-CY&_user=2322062&_coverDate=09,2F30,2F1984&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1655468263&_rerunOrigin=google&_acct=C000056895&_version=1&_urlVersion=0&_userid=2322062&md5=09397a6e327acf15899ed3f7ddc83a82&searchtype=a (more)
  10. Thom, B.G., Wright, L.D. and Coleman, J.M. (1975). Mangrove ecology and deltaic-estuarine geomorphology: Cambridge Gulf-Ord River, Western Australia. J. Ecol. 63(1): 202-232. Available online: http://www.jstor.org/stable/pdfplus/2258851.pdf (more)
  11. Shine, R., Ellway, C.P. and Hegerl, E.J. (1973). A biological survey of the Tallebudgera Creek estuary. Operculum 3(5-6): 59-83. Available online: (more)

Biological Interactions
Relation Taxon GroupSorted ascending
InhabitedBy Melobasis_purpurascens Beetles
InhabitedBy Paradisterna_plumifera Beetles
InhabitedBy Rhytiphora_pulverulea Beetles
PreyOf Ceresium Coleoptera
HasEpiphyte Coccocarpia_palmicola Lichens
HasEpiphyte Dirinaria_applanata Lichens
HasEpiphyte Graphis_cincta Lichens
HasEpiphyte Haematomma_stevensiae Lichens
HasEpiphyte Parmelia_erumpens Lichens
HasEpiphyte Parmotrema_saccatilobum Lichens
HasEpiphyte Ramalina_nervulosa Lichens
HasEpiphyte Ramalina_pacifica Lichens
HasEpiphyte Ramalina_subfraxinea_nortstictica Lichens
HasEpiphyte Sarcographa_subtricosa Lichens
HasEpiphyte Sclerophyton_conspicuum Lichens
HasEpiphyte Acrolejeunea_aulacophora Liverworts
HasEpiphyte Cheilolejeunea_intertexta Liverworts
HasEpiphyte Cololejeunea_lanciloba Liverworts
HasEpiphyte Frullania_ericoides Liverworts
HasEpiphyte Frullania_subtropica Liverworts
HasEpiphyte Lejeunea_flava Liverworts
HasEpiphyte Leptolejeunea_maculata Liverworts
HasEpiphyte Macromitrium_aurescens Mosses
HasEpiphyte Bostrychia_calliptera RedAlgae
HasEpiphyte Bostrychia_moritziana RedAlgae
HasEpiphyte Bostrychia_simpliciuscula RedAlgae
HasEpiphyte Caloglossa_adhaerens RedAlgae
HasEpiphyte Caloglossa_stipitata RedAlgae
HasEpiphyte Gelidium_sp RedAlgae
OccursWith Acanthus_ilicifolius Vascular_Plants
OccursWith Acrostichum_speciosum Vascular_Plants
OccursWith Aegialitis_annulata Vascular_Plants
OccursWith Aegiceras_corniculatum Vascular_Plants
OccursWith Avicennia_marina Vascular_Plants
OccursWith Bruguiera_exaristata Vascular_Plants
OccursWith Bruguiera_gymnorhiza Vascular_Plants
OccursWith Bruguiera_parviflora Vascular_Plants
OccursWith Bruguiera_sexangula Vascular_Plants
OccursWith Camptostemon_schultzii Vascular_Plants
OccursWith Ceriops_australis Vascular_Plants
OccursWith Ceriops_pseudodecandra Vascular_Plants
OccursWith Ceriops_tagal Vascular_Plants
OccursWith Cynometra_iripa Vascular_Plants
OccursWith Diospyros_geminata Vascular_Plants
OccursWith Heritiera_littoralis Vascular_Plants
OccursWith Hibiscus_tiliaceus Vascular_Plants
OccursWith Lumnitzera_littorea Vascular_Plants
OccursWith Lumnitzera_racemosa Vascular_Plants
OccursWith Nypa_fruticans Vascular_Plants
OccursWith Osbornia_octodonta Vascular_Plants
OccursWith Rhizophora_X_lamarckii Vascular_Plants
OccursWith Rhizophora_apiculata Vascular_Plants
OccursWith Rhizophora_mucronata Vascular_Plants
OccursWith Rhizophora_stylosa Vascular_Plants
OccursWith Scyphiphora_hydrophylacea Vascular_Plants
OccursWith Sonneratia_alba Vascular_Plants
OccursWith Sonneratia_caseolaris Vascular_Plants
OccursWith Sporobolus_virginicus Vascular_Plants
OccursWith Tecticornia_halocnemoides Vascular_Plants
OccursWith Xylocarpus_granatum Vascular_Plants
OccursWith Xylocarpus_moluccensis Vascular_Plants
OccursWith Barringtonia Vascular_Plants