  Pseudo-arcs are the higher dimensional analogues of arcs in a projective
plane: a pseudo-arc is a set $\mathcal{A}$ of $(n-1)$-spaces in
$\mathrm{PG}(3n-1,q)$ such that any three span the whole space. Pseudo-arcs of
size $q^n+1$ are called pseudo-ovals, while pseudo-arcs of size $q^n+2$ are
called pseudo-hyperovals. A pseudo-arc is called elementary if it arises from
applying field reduction to an arc in $\mathrm{PG}(2,q^n)$.
  We explain the connection between dual pseudo-ovals and elation Laguerre
planes and show that an elation Laguerre plane is ovoidal if and only if it
arises from an elementary dual pseudo-oval. The main theorem of this paper
shows that a pseudo-(hyper)oval in $\mathrm{PG}(3n-1,q)$, where $q$ is even and
$n$ is prime, such that every element induces a Desarguesian spread, is
elementary. As a corollary, we give a characterisation of certain ovoidal
Laguerre planes in terms of the derived affine planes.
