Acer japonica.
If it has Japanese maple leaves, then it's obviously a Japanese Maple!
Bonsai is an art, practiced using trees and shrubs. There is no scientific name for bonsai. Any individual bonsai has the same scientific name as the same variety in the ground. For example, a Japanese Maple tree in a garden is Acer palmatum, a Japanese Maple bonsai is also Acer palmatum.
Acer palmatum
The scientific name for the Red Maple is the Acer rubrum.
The scientific name for the Red Maple is the Acer rubrum.
Acer saccharum
The red maple is an angiosperm. Angiosperm is a term that refers to trees of a broad leaved variety.
Well there are several species of maple trees, all with individual species names; however, all of them are in the genus Acer. For example sugar maple is Acer saccharum and chalk maple is Acer leucoderme.
The scientific name of the Chinese maple tree is Acer buergerianum.
Maple tree = 椛 (momiji)
Acer
acer