Alismataceae . . . . . . . Water-plantains
Emergent water plants
Alisma . . . Water-plantain
Alisma plantago-aquatica . . . . Greater Water-plantain
Widespread in ponds and wet areas
Baldellia . . . Lesser Water-plantain
Baldellia ranunculoides . . . Lesser Water-plantain
Wet places and shallow water; scattered over BI
Damasonium . . . Starfruit
Damasonium alisma . . . . Starfruit
Muddy margins of ponds; rare, C En (pics G John)
Luronium . . . Floating Water-plantain
Luronium natans . . . . Floating Water-plantain
Local in acid lakes and canals esp. in Wa and N & C En; (pic 1 by Robbie Blackhall-Miles)
Sagittaria . . . Arrowhead
Sagittaria sagittifolia . . . . Arrowhead
Wet places and shallow water; scattered over BI esp. in S
A couple of other spp. are rarely naturalised
Also Damasonium alisma (Starfruit), which has star-shaped fruit and is a rare plant of muddy pond edges in Surrey/Bucks.