The present note is a continuation of our work in [5], [6] and [7] on constructing varieties of small types given by reasonably simple recursive lists of equations, having solvable word problem, but undecidable equational theory (and thus uniformly unsolvable word problem). Here we give an example of a semigroup variety of such kind, inspired by some ideas of Wells [16]. This, in a certain sense, unifies our previous results in this field.