  Excitonic superfluidity in double phosphorene monolayers is investigated
using the BCS mean-field equations. Highly anisotropic superfluidity is
predicted where we found that the maximum superfluid gap is in the BEC regime
along the armchair direction and in the BCS-BEC crossover regime along the
zigzag direction. We estimate the highest Kosterlitz-Thouless transition
temperature with maximum value up to $\sim 90$ K with onset carrier densities
as high as $4 \times 10^{12}$ cm$^{-2}$. This transition temperature is
significantly larger than what is found in double electron-hole few-layers of
graphene. Our results can guide experimental research towards the realization
of anisotropic condensate states in electron-hole phosphorene monolayers.
