Finite 4-primary groups with disconnected Gruenberg–Kegel graph containig a triangle

We give a description of finite 4-primary groups with disconnected Gruenberg–Kegel graph containing a triangle. As a corollary, finite groups whose Gruenberg–Kegel graph coincides with the Gruenberg–Kegel graph of $^3D_4(2)$ are exemplified, which generalizes V. D. Mazurov' description of finite groups isospectral to the group $^3D_4(2)$.