  Electrical transport measurements are used to study the Rh-doped NaFeAs
superconductor series with a focus on the tetragonal phase. The resistivity
curvature has an anomalous temperature dependence evidencing in the phase
diagram two crossover regions of changes in the scattering rate, the effective
mass as well as of the charge carrier density. The first crossover region is
directly connected to the structural transition and resembles the onset of
resistivity anisotropy. The second crossover region can as well be deduced from
the temperature dependent Hall coefficient. A comparison to literature NMR data
suggests this region to be connected with nematic fluctuations far above the
tetragonal to orthorhombic phase transition.
