It's the exact same size and speed. It has a one hit kill like the tarantula and you can kill it in one hit.
You enter the boss chamber and its spawn point is randomized.
The accompanying song is eight minutes long, but you would only know that by looking it up on YouTube.
A second encounter happens later in the game where there's a tarantula and a scorpion.
Not to "Um ackshually", but I swear I remember you can basically walk on tarantulas/scorpions and that they won't attack as long as you don't have your net out (At least in New Horizons).
I've never tried to, tbh. If I tiptoe towards a tarantula, it's only to catch it. I have never tried to talk on one.
I get why, it seems like common sense, but now I recall being surprised when an island tour took me to a special island filled with them and how they left me alone as I went around.
But as soon as the net came out, there was no such mercy.
That's actually really cool. They actually leave you alone if you don't make to catch them.