Finite semigroups that are minimal for not being Malcev nilpotent
  We give a description of finite semigroups $S$ that are minimal for not being Malcev nilpotent, i.e. every proper subsemigroup and every proper Rees factor semigroup is Malcev nilpotent but $S$ is not. For groups this question was considered by Schmidt. 
E. Jespers and M. H. Shahzamanian
math.GR