It is grey or shiny black in colour,[2] with spiny structures (conules) dotting the surface.

[3] I. strobilina inhabits marine waters, specifically those of the Caribbean Sea including off the coast of Florida, the Virgin Islands, Cuba and Venezuela.

This species is the most abundant sponge in the Abrolhos reef, where it grows exposed to many predatory fishes.

I. strobilina has been found to have chemical defences against predation by fishes: when force-fed with it in a study of three sponge species, the fish Holacanthus tricolor was temporarily paralysed and exhibited a loss of balance.

[7] The chemicals involved in repelling predators have been extracted and identified as the metabolite and sesterterpene variabilin, and its isomer strobilin.