Schmryptopen Edition: #11D-Juvenile Sclerogardius

From the moment they are live-birthed, Sclerogardius enter a feeding frenzy that allows them to accumulate the nutrients necessary to grow the heavy plates that are their most recognizable feature. Though they aren't optimized for free-swimming, the plates do provide some protection from predators even before the maturing creature takes up residence in a hole in the lymphatic substrate.