Peipiaosteus pani (Liu and Zhou 1965, Zhou 1992, Aptian, Early Cretaceous) nests with Chondrosteus in the LRT. It exposes the dorsal skull, which is missing in Chondrosteus. Several gill sets are exposed and preserved here. Is one an operculum? Compare to Chondrosteus.

Chondrosteus acipenseroides (Agassiz 1843; Egerton 1858; Early Jurassic 190mya; 1.2m; BMNH P3361) is a traditional sturgeon relative, but here nests with basking sharks and paddlefish. Here a shark-like gill basket is overlapped by a single opeculurm and a series of ventral branchials, like a bony fish, all by convergence. The jaws lacked teeth.

Strongylosteus hindernburgi (Henning 1925; originally Chondrosteus hindenburgi Pompeckj 1914; Early Toarcian, Early Jurassic; 3-4.5m) is traditionally considered "related to modern sturgeons, but with a different kind of mouth." Here it nests with Chondrosteus between placoderms and spiny sharks.