There are two independent contributors for today's photographs. In an intriguing coincidence, both took photographs of this plant at Ganna Walska Lotusland in July of last year! Thank you to Mike Bush, the executive director of Lotusland, for photographs 2 and 3 and “yousatonmycactus”@UBC Botanical Garden Forums (aka Guy Webb) of Ventura, California for the first image. Guy is one of the kind docents at Lotusland and has also shared a more images of the plant in this thread. Thanks to both of you for helping to continue the series on Australian plants – more to come!
If you're visiting Lotusland (follow the instructions on their web site re: booking a tour), Mike notes that this plant “is growing in our Visitor Entry area, next to the Parking Lot. Planted in 1993 the tree is now about 25 feet tall and is covered with flowers in mid-July when it is nearly leafless.”
Illawara flame tree is native to the coastal forests of eastern Australia, ranging from the tropical rainforests of Queensland south to the (more) temperate forests of New South Wales. Like the Dombeya from over a week ago, it is a member of the mallow family (or Malvaceae), though much literature will instead state it belongs to the Sterculiaceae, as Michael F noted in the comments on that entry. The Malvaceae Info web site delves deep into the reclassification of the Malvaceae and (former) allied families, if you'd like to read more.
The Malvaceae Info web site also provides an illustration of why this plant has the epithet acerifolius, or “leaves of Acer (maple)” in its photo gallery of the genus Brachychiton.
For more reading about the Illawara flame tree, please visit the Association of Societies for Growing Australian Plants' page on Brachychiton acerifolius or Wikipedia. Dias com árvores also has an entry on Brachychiton acerifolius – if you don't understand Portuguese, you can still appreciate the photography.