How many creatures and variants are in Ark Survival Evolved?

Solution 1:

According to the creatures list (text version), there are:

• 29x Dinosaurs
• 35x Mammals (5 alternative forms)
• 17x Reptiles
• 10x Birds
• 11x Fishes (1 alternative form)
• 23x Invertebrates (7 alternative forms)
• 55x Fantasy (15 alternative forms)
• 8x Mechanical (1 alternative form)
• 44x Aberrant versions
• 6x Teks
• 17x Corrupteds
• 2x Enrageds
• 20x R-creatures
• 31x VR creatures
• 21x X-creatures
• 12x Malfunctioned Teks
• 16x Alphas
• 27x Brutes
• 28x Events (3 alternative forms)
• 39x Bosses/Titans (33 alternative forms)

Making a grand total of 451 creatures, counting each version or alternative forms.
And other 3 creatures yet to be released.