Appearance
H. whitmaei is now classified as a separate species from H. nobilis. H. whitmaei used to be included in H. nobilis.
Seasonal trends from two populations of H. whitmaei were investigated, between the Great Barrier Reef and Ningaloo Reef. The gonad index was found to peak between April and June. Macroscopic and histological analysis revealed “that large germinal tubules, positioned centrally on the gonad basis, progressed through four maturity stages: growing (II); mature (III); partly spawned (IV); and spent (V)”.
In one study in 2003, they were unsure why “up to 23% of H. whitmaei specimens were hidden from some time during the night until midday". Although in another study to obtain ecological data on H. whitmaei, “rates of activity in marked specimens increased significantly in the initial hours after marking”. This suggests that marking the specimens likely compromises the research.

