Hibiscus calyphyllus Cav.

Perennial herb to 2 m tall. Leaves to about 12 cm long, shallow to deeply 3-5 lobed. Epicalyx of 5 bracts. Flowers clear yellow with crimson centre; late summer to autumn. Capsule about 2.5 cm long with whiskered valves. [H. calycinus Willd.]

Tropical and S South Africa, Madagascar, Mascarenes

Source: Beers, L.; Spencer, R. (1997). Hibiscus. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.

Distribution map
kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Rosanae
order      Malvales
family       Malvaceae
genus        Hibiscus L.