Lampreys belong to the Phylum Chordata, specifically the Subphylum Vertebrata. Archosaurs belong to the Phylum Chordata, specifically the Class Reptilia within the Subphylum Vertebrata.
Sea Lampreys belong to the order Petromyzontiformes.
Lampreys are in the superclass Agnatha, jawless fish. They are of the class Cyclostomata, which includes hagfish, as opposed to the extinct Ostracoderms.
Jawless fish belong to the class Agnatha within the phylum Chordata. They are primitive fish lacking jaws, and include groups like lampreys and hagfish.
Jawless fish are the oldest group of fish, belonging to the class Agnatha. Within this class, they are further divided into two orders: the Petromyzontiformes (lampreys) and the Myxiniformes (hagfish).
jawless fishes
n. 1. a class of eel-shaped chordates with a cartilaginous skeleton lacking jaws, scales, and pelvic fins. Among these are the lampreys and hagfishes. There are some extinct forms.
Wolves belong to the class Mammalia.
Tigers belong to Class Mammalia.
Opossums belong to the class mammalia.
The lampreys and remora do not share a class. While both are symbiotes (both can attach to another fish), the lamprey is a parasite, while the remora is a commensalist scavenger, who may even aid the larger host. A lamprey is a jawless fish; the remora is an ordinary fish with an extraordinary attribute.
Echidnas belong to the Class Mammalia and Order Monotremata.