A dephased $N\times N$ complex Hadamard matrix $H$ is called isolated if there is a neighbourhood $W$ around $H$ such that there are no other dephased complex Hadamard matrices in $W$.
For example, the Fourier matrices: $F_2$, $F_3$, $F_5$, $F_7$ and other Fourier matrices $F$$_p$ of a prime dimension $p$ are isolated. So is the spectral matrix $S_6^{(0)}$, and several other higher dimensional matrices mentioned in the catalogue.