  We present measurements of more than 80 magnetic Feshbach resonances in
collisions of ultracold $^{23}$Na$^{40}$K with $^{40}$K. We assign quantum
numbers to a group of low-field resonances and show that they are due to
long-range states of the triatomic complex in which the quantum numbers of the
separated atom and molecule are approximately preserved. The resonant states
are not members of chaotic bath of short-range states. Similar resonances are
expected to be a common feature of alkali-metal diatom + atom systems.
