Callitris macleayana 070925-6003

Description:

Australian National Botanic Garden, Canberra. The most distinctive of Australia's 17 Callitris species, this can reach possibly 40 m in height and occurs in subtropical rainforest margins in New South Wales, with outlying occurrence in far north Queensland. It has needle-like juvenile leaves usually in whorls of 4, persisting for many years and sometimes associated with cones that have 8 scales instead of the usual 6 in Callitris. Specimens of such branches prompted Ferdinand Mueller to name it as a distinct genus, Octoclinis, in 1858, but he transferred the species to Callitris in 1860. The cones are also unusual for their 6 scales being long-pointed and virtually of equal length, rather than 3 long alternating with 3 short as in most other species of the genus. I wonder if this might indicate the species is basal in the Callitris clade, close to where the genus Actinostrobus possibly diverged. That has cones of similar shape, though with the addition of many rows of bracts beneath the cone-scales.