Identification: Shrub, leaves in 3's, skinny white clawed petals

Here is another shrub in Morton Park at English Bay, in a planting with several uncommon plants. This looks unusual to me. Leaves are a bright slightly yellowish green, in threes with a winged rachis (I "collect" plants with a winged rachis, a term I learned here, so this plant appeals to me for that). Stems are green, somewhat squared. Flowers are maybe 4cm across but petals are thin and ragged with clawed attachment ends. Flowers had four to seven petals. This is armed with some great spines - I implied in another thread that the tree would not be seen on city streets because of the hefty spines, but this shrub is similarly armed.

 

Poncirus trifoliata.

 

Uh-oh. Thanks, Michael. I see that I posted one of these for appreciation two years ago (!), but I don't have to be too hard on myself - that one was was all stems and fruits, no leaves at all. I don't think I could have expected myself to be able to recognize this from that posting, even if I had remembered it.
Appreciation: - Citrus trifoliata in Stanley Park
At least the name sounded familiar, even though it seems to have been renamed Citrus trifoliata, or did that name not stick?