Lampreys possess a skull, vertebrae and are assigned to the class Cephalaspidomorphi within the subphylum Vertebrata. Adults of most species of lampreys are parasitic with a funnel-like mouth that attaches to the host fish by suction.
What type of skeleton do lampreys have?
Lampreys lack a mineralized skeleton but possess cartilaginous neurocranial and viscerocranial elements. In lampreys, the visceral skeleton develops as a fused branchial basket supporting the pharynx.
Do lampreys have a bony skeleton?
Lack a bony skeleton and jaws (bones may have been secondarily lost, as there is evidence to suggest that their ancestors possessed a bony skeleton). No paired fins (pectoral, pelvic), but do have unpaired fins: dorsal and caudal (tail) fin.
Do lampreys have brains?
Lampreys have a very small brain, as compared with most gnathostomes, and their telencephalon, in particular, is very tiny. The telencephalic hemispheres arise as an unpaired and solid rudiment, which later divides into two portions (Scott, 1887).
Does a hagfish have a skull?
Not only are hagfishes jawless, but they are also boneless. They have a skull made of cartilage, but no vertebrae.
Do lampreys have vertebrates?
Unlike hagfishes, with which they were once classified, lampreys have a complete braincase and rudimentary true vertebrae. Uniquely among living vertebrates, lampreys also have a single “nostril” on the dorsal side of the head — a feature they share with various fossil jawless fish, which had a similar opening.