1	"Corolla 9 mm long or more"	2
1	"Corolla less than 9 mm long"	5
2	"Flower predominantly white (rarely flushed red); sepals 4 mm long or more; fruiting pedicel strongly recurved after fertilisation"	"Fumaria capreolata"
2	"Flower predominantly pink; sepals less than 4 mm long; fruiting pedicel erect to slightly recurved"	3
3	"Fruit wider than long, truncate to shallowly emarginate at apex; lower petal distinctly spathulate"	"Fumaria officinalis"
3	"Fruit longer than wide, or ±as long as wide, rounded to pointed at apex; lower petal linear to narrowly spathulate"	4
4	"Inner petals with pale yellow median streak (becoming more prominent on drying); lower petal more than 0.5 mm wide medially; peduncle and pedicel rather stout; pedicel remaining erect in fruit; fruit rather straight-sided, truncate at base, distinctly tuberculate-rugulose at maturity"	"Fumaria bastardii"
4	"Inner petals not or rarely with median yellow streak; lower petal less than 0.5 mm wide medially; peduncle and pedicel slender; pedicel commonly spreading to slightly recurved in fruit; fruit rounded, smooth to minutely tuberculate"	"Fumaria muralis"
5	"Sepals less than 1.5 mm long (usually less than 1 mm); bracts exceeding flowering pedicel"	6
5	"Sepals more than 1.5 mm long; bracts longer or shorter than flowering pedicel"	7
6	"Flowers white (sometimes becoming flushed red after fertilisation) or rosy-pink, but inner petals without dark purplish apex; largest leaf segments only rarely wider than c. 0.5 mm"	"Fumaria parviflora"
6	"Flowers pink; inner petals with dark purplish apex; largest leaf segments more than 0.5 mm wide"	"Fumaria indica"
7	"Sepals broadly ovate to subrotund, wider than corolla; bracts exceeding flowering pedicel"	"Fumaria densiflora"
7	"Sepals ovate, narrower than corolla; bracts shorter than or equal to flowering pedicel"	8
8	"Fruit wider than long, truncate to shallowly emarginate at apex; lower petal distinctly spathulate"	"Fumaria officinalis"
8	"Fruit no wider than long, rounded to subacute at apex; lower petal linear to narrowly spathulate"	9
9	"Inner petals with median yellow streak; pedicel remaining erect in fruit; fruit rather straight-sided, truncate at base, distinctly tuberculate-rugulose"	"Fumaria bastardii"
9	"Inner petals not or rarely with median yellow streak; pedicel commonly arcuate and spreading in fruit; fruit rounded at base, smooth to minutely tuberculate"	"Fumaria muralis"