I used to be really afraid of the dark as a child, not of monsters lurking in it or anything, but just people coming into my house to murder me. Not sure why that was, as the neighborhood was always safe and my house was especially protected, never having a chance to be targeted by a burglar, yet I was just very frightened by the idea of being across the house from my parents' protection while being stabbed to death by an intruder, so until I was about ten I would often sleep in their bed instead of my own. They never understood my fear but were kind enough to always let me in if I couldn't fall asleep in my room in time before that fear would set in. Now, when it comes to fears of just looking at pictures or videos online, I've always had an instinctual fear reaction (scrolling away quickly) to big spiders, having never actually encountered a big one IRL. Other things have unsettled me a bit, like that "uncanny valley" stuff, mainly people's eyes and unnatural smiles in weird photos of them (example of this most recently is when I was reading about this story of a lady named Kelly Ronahan who had an insanity called Munchausen syndrome that caused her to tear her legs apart, look up pictures of her, she has an appearance in her face that sends fear to me), but honestly the one fear that has always stuck with me, from childhood to now, is big spiders. Scorpions are things I can deal with, so it isn't every arachnid, but the hairy, multi-eyed, hook-mouthed creatures are what I can never observe without a negative feeling.