Trees, shrubs or herbs, some climbing or twining, monoecious or dioecious; stems
sometimes succulent and/or with latex; xylem vessel perforation plates scalariform, simple or
both. Leaves alternate or rarely opposite or whorled, simple or sometimes palmately lobed or
compound, the margins entire or serrate; stipules free, rarely connate or absent, deciduous or
persistent; venation pinnate or palmate; indumentum simple, stellate or lepidote, sometimes
absent. Inflorescences terminal or axillary, occasionally cauliflorous, basically cymose, thyrses
or racemes, or these often grouped into panicles; flowers solitary or in glomerules, these often
grouped into spiciform or capitate thyrses or cyathia. Flowers: unisexual, actinomorphic,
anemophilous or entomophilous, the parts hypogynous, rarely perigynous (in Bridelia). Perianth
segments mostly not differentiated into sepals and petals, in some genera differentiated into
sepals and coloured petals; sepals free or rarely connate, valvate or imbricate, sometimes reduced
or absent, (1-) 3 - 6 (-8), sometimes distinctly coloured; petals if present free, variously coloured;
disc present or absent, intrastaminal or extrastaminal, entire, annular or dissected into separate
glands. Stamens (1 -) 3 - 50 (- 300) (always solitary in Euphorbia); filaments free or connate;
anthers mostly 2-locular, basifixed or rarely dorsifixed, sometimes the thecae separate,
longitudinally dehiscent, introrse or extrorse; pollen grains tectate or semi-tectate, (2-) 3 (- 10)-
colporate (inaperturate or polytreme). Gynoecium syncarpous; ovary (1 -) 2 - 5 (- 20)-locular;
placentation axile; ovules 1 or 2 in each locule, anatropous or hemitropous, rarely orthotropous,
inserted beneath an obturator, crassinucellate with 2 integuments; nucellus often beaked; embryo
sac mostly 8-nucleate; styles usually 3, free or variously connate, each usually bifid, rarely
multifid. Fruits capsular, schizocarpic, elastically dehiscing into 2-valved cocci from a persistent
columella, sometimes baccate or drupaceous. Seeds 1 or 2 per locule (rarely one or two seeds
per fruit); seed-coat thin to indurate, sometimes with sarcotesta; endosperm fleshy, copious or
moderate, rarely scanty or absent; embryo straight to arcuate or folded; cotyledons usually
broader than radicle, thin to moderately thick.
Cosmopolitan, except for the arctic and cool temperate regions of northern Hemisphere;
mainly in tropical and subtropical regions, ca 322 genera and ca 8900 species; 70 genera and ca
410 species in India.
Notes.
Recent molecular studies and the evidences obtained therein have changed the
concept of the family Euphorbiaceae and the trend now is to divide the family into several
segregate families and merger of several genera. The creation of the family Phyllanthaceae
based on the subfamily Phyllanthoideae of Euphorbiaceae and the merger of the genera Breynia,
Glochidion and Sauropus with Phyllanthus (Hoffmann et al., 2006 and Kathriarachchi et al.,
2006) necessitate a number of name changes. Accordingly, Chakrabarty and Balakrishnan (2009)
transferred the taxa of the above genera occurring in Indian subcontinent to Phyllanthus.
However, dividing the family Euphorbiaceae into segregate families is a new concept and needs
wide consensus before acceptance. Hence, in the present treatment, Euphorbiaceae, sensu lato
is maintained.
Literature.
BALAKRISHNAN, N. P. & T. CHAKRABARTY (2007). The family Euphorbiaceae
in India - a synopsis of its profile, taxonomy and bibliography. Dehra Dun. CHAKRABARTY, T. & N.
P. BALAKISHNAN (2009). Transfer of Indian species of Breynia, Glochidion and Sauropus to Phyllanthus
(Phyllanthaceae) - new combinations and new names. J. Econ. Taxon. Bot. 33(3): 712 - 716. GOVAERTS,
R., D. G. FRODIN & A. RADCLIFFE-SMITH (2000). World Checklist and Bibliography of Euphorbiaceae
(and Pandaceae). Vols. 1 - 4. Kew. HOFFMANN, P., KATHRIARACHCHI, H. & K. J. WURDACK(2006). A phylogenetic classification of Phyllanthaceae (Malpighiales; Euphorbiaceae sensu lato). Kew
Bull. 61(1): 37 - 53. KATHIARACHCHI, H., R. SAMUEL, P. HOFFMANN, J. MLINAREC, K. J.
WURDACK, H. RALIMANANA, T. F. STUESSY & M. W. CHASE (2006). Phylogenetics of tribe
Phyllantheae (Phyllanthaceae; Euphorbiaceae sensu lato) based on nrITS and plastid matK DNA sequence
data. Amer. J. Bot. 93 (4): 637 - 655.
KEY TO THE SUBFAMILIES
1 a. Locules of ovary each with 2 ovules; milky latex absent, intraxylary phloem, and stinging
hairs absent; indumentum simple or rarely lepidote or dendritic; embedded foliar glands rare;
pollen grains binucleate; seeds ecarunculate; endosperm copious or absent
2
b. Locules of ovary each with a single ovule; latex often present; indumentum various; pollen
grains binucleate or trinucleate; seeds carunculate or not; endosperm usually copious
3
2 a. Leaves alternate, very rarely opposite, stipulate, simple and unlobed (trifoliolate in Bischofia);
petals present or absent; pollen grains tricolporate or porate, sexine not with conspicuous
spines; seeds ecarunculate
b. Leaves alternate, opposite or whorled, stipulate or exstipulate, simple or trifoliolate; petals
absent; pollen grains colpoidorate to porate, sexine spiny; seeds carunculate or not
b. Latex reddish or yellowish to milky (rarely absent); laticifers usually present, articulate or
not; leaves simple to palmately lobed or compound; pollen grains binucleate or trinucleate
4
4 a. Latex clear to reddish or whitish, innocuous; laticifers articulate or not; leaves often palmately
veined, lobed or compound; indumentum simple or often stellate; inflorescence dichasial
paniculate to spicate; bracts usually not biglandular at base; sepals imbricate to valvate,
usually completely covering anthers in bud; petals mostly present; floral disc often with
staminodes; pollen grains mostly porate or inaperturate with ‘crotonoid’ pattern of polygonally
arranged sexinous processes
b. Latex whitish, often caustic or poisonous; laticifers not articulate (rarely absent); leaves
simple (rarely lobed), pinnately veined or triplinerved; indumentum simple or often absent,
never typically stellate; inflorescence racemose, spicate, capitate or cyathial; bracts mostly
biglandular at base; sepals imbricate or obsolete; anthers mostly not covered in bud; petals
absent; floral disc usually without staminodes; pollen grains tricolporate, colpi usually
marginate, sexine reticulate to more often perforate-lectate
