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 formation appears to have been laid down in a tropical environment somewhat similar to the Bahamas today, and on the basis of fossil evidence an Early Jurassic (Sinemurian) age has been proposed for the Gibraltar Limestone, though in appearance it has a strong resemblance to the Carboniferous Limestone that underlies large parts of England and Wales.
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Gravisauria split off in the Early Jurassic, around the Pliensbachian and Toarcian, 183 million years ago, and Aquesbi thought that this was part of a much larger revolution in the fauna, which includes the disappearance of Prosauropoda, Coelophysoidea and basal Thyreophora, which they attributed to a worldwide mass extinction.
In the eastern Canadian province of Nova Scotia, scientists have unearthed prosauropods from the McCoy Brook Formation, which is about 200 to 197 million years old, from the Early Jurassic Hettangian stage.
One of these had been recovered from early Jurassic strata at the south bank of the Severn river, at the Aust Cliff.
This specimen was found in Voyizane, Joe Gqabi District, Cape Province, in rocks of the upper Elliot Formation, a rock formation that dates to the early part of the Early Jurassic (Hettangian–Sinemurian, approximately 200 to 190 million years ago).