Aizoaceae angular-pigface Cape-fig carpobrotus-glaucescens coastal creeping-succulent daisy-like-flowers drought-resistant dune-stabilizer edible fire-resistant fleshy flora flower flowers food groundcover Hottentot-plant ice-plant invasive medicinal nutritional open perennials pigface pink-purple plant plant-mat prostrate salt-substitute salt-tolerant sand-dunes sand-stabilizer smooth-leaves sour-fig strand-ivy succulent sunlight sunshine thick triangular-leaves yellow bee bees insect insects