Here is the seed of an apple (Malus domestica). When apple seeds grow into trees, they usually differ significantly from their parents, possibly an evolutionary mechanism to avoid methodical destruction (e.g. by pests). This seed measures 4.6 x 8.0 mm.
Equipment used: Canon EOS Rebel T5i with a standard zoom lens (EF-S 18-55 mm) on a 49 mm long extension tube.