Here's a photo of the two poroporo species side-by-side at Hinewai Reserve near Akaroa. Solanum laciniatum is on the left and Solanum aviculare is on the right. Note how the petals of Solanum laciniatum are larger with a frilled margin, creating an indent at the tip of each petal , while the petals of Solanum aviculare are smaller and pointed with no frilly margin.

(More details about this observation.)