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We present MeerKAT Absorption Line Survey (MALS) observations of the HI gasin the Klemola31 galaxy group ($z=0.029$), located along the line of sight tothe radio-loud quasar PKS2020-370 ($z=1.048$). Four galaxies of the group aredetected in HI emission, and HI absorption is also detected in front ofPKS2020-370 in Klemola31A. The emission and absorption are somewhatcompensating on the line of sight of the quasar, and the derived column densityof the absorption appears under-estimated, with respect to the neighbouringemission. A symmetric tilted-ring model of Klemola31A, assuming the absorbinggas in regular rotation in the plane, yields a rather high spin temperature of530K. An alternative interpretation is that the absorbing gas is extra-planar,which will also account for its non-circular motion. The NaI/CaII ratio alsosuggests that the absorbing gas is unrelated to cold HI disk. Two of thegalaxies in the Klemola group are interacting with a small companion, andreveal typical tidal tails, and velocity perturbations. Only one of thegalaxies, ESO400-13, reveals a strong HI deficiency, and a characteristicram-pressure stripping, with a total asymmetry in the distribution of its gas.Since a small galaxy group as Klemola31 is not expected to host a denseintra-group gas, this galaxy must be crossing the group at a very highvelocity, mostly in the sky plane.

Mapping HI 21-cm in the Klemola 31 group at z = 0.029: emission and absorption towards PKS2020-370