Briggs and Johnson, Hopkinsiaceae and Lyginiaceae 
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Key to families of Poales 
Restionaceae and allied families are generally included in the order Poales, but the 
circumscription of that order has varied in different classifications. The Angiosperm 
Phylogeny Group (APG 1998) included 15 families in Poales. The following key, 
however, covers only the more restricted circumscription of seven families by 
Dahlgren et al. (1985), together with the two new families now described. This range 
includes the families considered to be closest relatives of the Restionaceae and of the 
members of the Amrthrin clade. 
1 Anthers 2-sporangiate, not lobed, with 1 dehiscence slit . 2 
1* Anthers 4-sporangiate, 2-lobed, opening by 2 longitudinal slits . 3 
2 Flowers mostly with tepals; male flowers with 2-3 stamens, females with 1-3 carpels; 
pollen endexine present . Restionaceae 
2* Flowers naked; males consisting of a single stamen; females of one carpel; pollen 
endexine lacking. Centrolepidaceae 
3 Fruit a drupe. 4 
3* Fruit a capsule, nutlet, achene or follicle. 6 
4 Leaf sheaths closed; leaf blades larger than sheaths and ending in a tendril . 
. Flagellariaceae 
4* Leaf sheaths open; leaf blades larger or smaller than sheaths and not ending in a 
tendril . 5 
5 Stems terete, without scabrid margins, unbranched below the inflorescence; leaf 
blades plicate, larger than sheaths; plants with hermaphrodite flowers; ovary 
trilocular; stylar branches or sessile stigmatic areas 3; stigmas covered with short 
papillae . joinvilleaceae 
5* Stems flattened, with scabrid margins, repeatedly branched; leaf blades not folded, 
smaller than sheaths; plants dioecious; ovary unilocular; style single; stigmas covered 
with long stigmatic branches that are themselves branched . Hopkinsiaceae 
6 Flowers bisexual, each with a 2-keeled bract (palea) opposite the subtending bract 
(lemma). Tepals ('lodicules') in one whorl (3 or fewer) . Poaceae 
6* Flowers unisexual, with 1 or more bracts; bracts not as above (not 2-keeled). Tepals 
in two whorls (mostly 3 + 3 or 2 + 2). 7 
7 Monoecious with male and female flowers together in the same spikelet; stamens 4 
or 6; culms striate with deep narrow crypts between broad sclerenchyma-capped 
ridges.*. Ecdeiocoleaceae 
7* Dioecious; stamens 3; culms not striate or with striations formed by narrow ridges 
of sclerenchyma not by deep crypts .. 8 
8 Leaf blades elongated, equitant (as if folded longitudinally with the 2 inner surfaces 
fused, so that the abaxial margin represents the leaf keel and the blade is vertically 
orientated); culms striate; stamen filaments not fused into a column . 
. Anarthriaceae 
8* Leaf blades of adult plants reduced to an awn at the apex of the sheathing base, not 
equitant; culms not striate; stamen filaments fused into a column . Lyginiaceae 
