  Deciding whether a planar graph (even of maximum degree $4$) is $3$-colorable
is NP-complete. Determining subclasses of planar graphs being $3$-colorable has
a long history, but since Gr\"{o}tzsch's result that triangle-free planar
graphs are such, most of the effort was focused to solving Havel's and
Steinberg's conjectures. In this paper, we prove that every planar graph of
maximum degree $4$ obtained as a subgraph of the medial graph of any bipartite
plane graph is $3$-choosable. These graphs are allowed to have close triangles
(even incident), and have no short cycles forbidden, hence representing an
entirely different class than the graphs inferred by the above mentioned
conjectures.
