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We use femtosecond time-resolved optical reflectivity to study the photoexcited quasiparticle (QP) dynamics in the iron-based 112 type superconducting (SC) samples Ca0.s2La0.1sFe1-xNixAs2,with x =0 and 0.024.In the parent sample,a fast and a slow relaxation emerge at temperatures below the magnetic-structure (MS) transition Tms ≈ 50 K and the SC transition Tc ≈ 33 K,respectively.The latter obviously corresponds to an SC QP dynamics,which is further confirmed in the x =0.024 sample with Tc ≈ 25 K.The former suggests that a partial of photoexcited QP relaxation through a pesudogap (PG) channel,which is absent in the doped x =0.024 sample without the MS transition.