206 
EUPHORBIACEAE 
Trees, shrubs or herbs, often with milky latex. Stipules usually present. Leaves usually alternate, 
opposite or rarely whorled, simple or rarely compound. Inflorescence diverse. Flowers unisexual, 
monoecious or dioecious, often reduced and in Euphorbia grouped into a cyathium. Tepals distinct 
or connate near*base. Stamens (1)5-many, variously arranged. Nectary disc sometimes present. 
Carpels (2)3(many), united into a compound ovary; style usually 1, divided into 2 or more stigmas; 
ovules 1-2 in each locule, pendulous, placentation axile. Fruit capsular, drupaceous or baccate. 
About 300 genera and 7500 species worldwide; 65 genera in Australia with 33 genera in the NT and 24 in 
the DR. [Airy Shaw, 1980a,b; Webster, 1994]. Important crop plants include: Ricinus communis L., the Castor 
Oil Plant; Hevea brasiliensis (A.Juss.) Muell.Arg., Para Rubber, a source of natural rubber; Manihot esculenta 
Crantz, Cassava or Tapioca. Species in the genera Acalypha, Codiaeum, Euphorbia and Jatropha are used as 
ornamentals. 
1. Leaves opposite or WhOrled ......sessessecseeteeeeessessessesnsssssasensensssseseesecnecsecnecsecnecnecnseneeneeseensess 2 
[Hn Deavesialternate saree orien ect eit ineteraetitesettcrttteltveseccsscresersceacsntsaartetasnstrstersticctessesesasets 3 
2. Leaves opposite; flowers in a cyathium; latex PreseMt........-esssesseesesseessesneesteeseesesseesneenes Euphorbia 
2. Leaves opposite or in whorl of 3; flowers not in a cyathium; latex absent... eres Choriceras 
3. Leaves with minute vesicular glands on the undersurface 4 
3. Leaves lacking vesicular glands on undersurface .........s.ssessessessessessessesseeneeneeneeneeneenseneeneens 5 
4. Leaves peltate or cordate; lacking stellate Mars ............esseecsessseseeeseeseesesseeseeesseseeeseesneesees Macaranga 
4. Leaf bases otherwise; if cordate then stellate hairs present.......s.sccsccseseseeeeseseseeseseeseeeeenes Mallotus 
5. Leaves with flattened glands at junction of blade and petiole «0.0.2.2... esseseeeeseeeteeeeteeeeneenes 6 
5. Leaves lacking flattened glands at junction of blade and petiole ........-..seeeeseestenenteens 7 
6. Inflorescence racemose; fruit a capsule .... Croton 
6. Inflorescence paniculate; fruit drupaceous Endospermum 
7. Flowers in a cyathium; latex present ............ssecsssecsersesesssssssssoescseessencessecerensscsscncneeneetsnsenss Euphorbia 
7. Flowers solitary or in fascicles, racemes, cymes OF PAaNiCles ........sesseesseesseeseeeseeseeseeeneenees 8 
8. Fruit fleshy, sometimes thinly $0..........csceccsscersesnssssctssoscussessestocevncnssessevstectecseerserecresessoesess 9 
SMe ETUit dry nerrrect ter ttcarececcenserrersstrssecmreseat tr veceestor. ternetitetsteveestestosenconttaetttatersters tutseetsttotesnst 16 
9. Inflorescence racemose, cymose or paniculate 10 
9. Inflorescence fasciculate or flowers SOLitary ..........-..-.:s-cscecssssssssssscsesesseescesssecsesssasesseosoese 11 
10. Leaves with a cluster of minute spine-like glands at the distal end of the petiole; 
domatia absent; female inflorescence a cyme; fruit a capsule Claoxylon 
10. Leaves lacking a cluster of minute spine-like glands at the distal end of the petiole; 
domatia + present; female inflorescence racemose; fruit fleshy .........sessecsessesseeseeseeseess Antidesma 
[i See Er Uite] OTM LON oer recttcetttseresreeterierttereteyiseetertstecrecerstsenbstesteta tes taccscattateacerset va jtaetiateresete 12 
11. Fruit <10 mm long, rarely to 12 mm in Breynia 13 
12. Fruit a globular, thinly fleshy capsule, drying hard, 3-4-lOCUIar.........seeseeseeseesseseeseesteseesees Petalostigma 
12s Fruitanindehiscent’drupesl-locularaeccssestrsesstttiectessccsterscseresencestapeeettttesnretteestayssttariietet? Drypetes 
13. Fruit 2-locular; undersurface of leaves tomentose, tertiary venation + parallel ................ Briedelia 
13. Fruit 3-locular; undersurface of leaves usually glabrous, 
14 
tertiarytvenation notet-parallel Mrrrccriecestrttssts.asestscesessesidstatevrectsenesetectestasttcasatevieesstrecacss 
