But given its deep sea habitat, Chondrocladia may well have been around for much longer – perhaps since the Mesozoic, as characteristic spicules (termed "microcricorhabds" or "trochirhabds"), almost identical to those of some living Chondrocladia, are known from Early Jurassic rocks almost 200 million years old.
The most common feature is the presence of spicules, long thin fingers of luminous gas which appear like the blades of a huge field of fiery grass growing upwards from the photosphere below.