Hi Maurillo,
I have observed something similar. I had 1
melaleuca which fitted the Pilbeam description very well, upper and central spines dark, lower radial spines white. When this plant almost rotted away (I could save two small offsets, which are mature now), I sowed the seeds of a fruit which was present. From these seeds I succeeded in growing 1 plant which looks quite a lot like your abnormal
melaleuca, more radials than normal
melaleuca and all radials are white. To me it also feels like the tubercles are softer than for the normal
melaleuca. I think that my abnormal
melaleuca is a hybrid, possibly with M. sphaerica or another dolichothele.
Attached are two habitat photos of M.
melaleuca, growing in forest. Photos are not of very good quality, because of the poor light in the forest.
Wolter ten Hoeve.