These stalked echinoderms averaged a height of about but occasionally ranged up to about 3 times that size. They, like other blastoids, superficially resemble their distant relatives, the crinoids or
sea lilies, having a near-identical,
planktivorous lifestyle living on the sea floor attached by a stalk. As with all other blastoids, species of
Pentremites trapped food floating in the currents by means of tentacle-like appendages.
Pentremites species lived in the early to middle
Carboniferous, from 360.7 to 314.6 Ma. Its
fossils are known from
North America. ==References==