Seismosaurus vs reptile genus

Seismosaurus and reptile genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Seismosaurus	Yes	No	No	No
reptile genus	Yes	No	No	No

As nouns, reptile genus is a hypernym of Seismosaurus; that is, reptile genus is a word with a broader meaning than Seismosaurus:

Seismosaurus: genus of large herbivorous dinosaurs of Cretaceous found in western North America
reptile genus: a genus of reptiles

Seismosaurus (noun)	reptile genus (noun)
genus of large herbivorous dinosaurs of Cretaceous found in western North America	a genus of reptiles