A basisphenoid is a bone which forms the back portion of the sphenoid - an unpaired bone in the neurocranium.
An alar canal is a bony tunnel through the basisphenoid bone of the skull, through which the maxillary artery and nerve pass.
An alar foramen is the opening at either end of the alar canal, the bony canal through the basisphenoid bone of the skull, through which the maxillary artery and nerve run.
Dari o. Valdivieso has written: 'Morphology of the Basisphenoid pits and related structures of the bat Otomops martiensseni (Chiroptera: Molossidae)' -- subject(s): Anatomy, Otomops martiensseni, Ear, Bats, Mammals