The name of a quartic curve: The product of the distance to the focus and to the directrix is the constant.

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It is like a question of the natural history in math, but I would like to know if the locus has a particular name. The equation of the curve is $(x+1)^2((x-1)^2+y^2)=1$. The curve includes a similar shape to Folium of Descartes which is cubic, but it has another part in the opposite side of the directrix: $x=-1$. The quartic curves formed in which the product of the distances to the two foci is constant have the names of Cassinian oval, but I could not find the name of this particular curve.