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We present three-dimensional, hybrid-kinetic numerical simulations of drivenAlfv\'{e}n-wave turbulence of relevance to the collisionless near-Earth solarwind. Special attention is paid to the spectral transition that occurs near theion-Larmor scale and to the origins of preferential perpendicular ion heatingand of non-thermal wings in the parallel distribution function. Several noveldiagnostics are used to show that the ion heating rate increases as thekinetic-Alfv\'{e}n-wave fluctuations, which comprise the majority of thesub-ion-Larmor turbulent cascade, attain near-ion-cyclotron frequencies. Wefind that ${\approx}75$-$80\%$ of the cascade energy goes into heating theions, broadly consistent with the near-Earth solar wind. This heating isaccompanied by clear velocity-space signatures in the particle energizationrates and the distribution functions, including a flattened core in theperpendicular-velocity distribution and non-Maxwellian wings in theparallel-velocity distribution. The latter are attributed to transit-timedamping and the pitch-angle scattering of perpendicularly heated particles intothe parallel direction. Accompanying these features is a steepening of thespectral index of sub-ion-Larmor magnetic-field fluctuations beyond thecanonical $-2.8$, as field energy is transferred to thermal energy. Thesepredictions may be tested by measurements in the near-Earth solar wind.

Hybrid-Kinetic Simulations of Ion Heating in Alfv\'{e}nic Turbulence