Last night after increasing the wetness in the terrarium of the female scorpion I keep, by letting fall drops of water from a small bottle, I decided to move her to a smaller enclosure in order to make good close up pictures of a female Centruroides flavopictus, a Mexican scorpion.
So I lifted the piece of pumice she was hiding on, and took Pavel, a male scorpion out of its small terrarium, and put him in the same, bigger, terrarium. I was doubting if I would let them meet each other, since scorpions can be cannibalistic, and I have the feeling that C. flavopictus prefers living solitaire.
I decided to give it a try, closely watching what was going to happen. The female stayed in the same spot, and the male slowly walked into her general direction. Suddenly he discovered the female, touched her, and grabbed her left claw with his right claw and held her. With his left claw he tried to grab her right one, which was a bit harder since it rested against a piece of pumice.
Both animals waved their tails, but I had the feeling that this was the beginning of the mating dance so I kept watching, ready to break them up if anything went wrong. The male started to pull the female walking backwards, next, it looked like he was pushing the female backwards, instead of her pulling him. I know that scorpions prefer a flat area for mating, and the substrate, consisting of small stones and sand was not a good place. The male kept pushing the female backwards until they both were standing on a small piece of wood, and the first dance started; tugging and pushing.
I made a few pictures, but since the lighting conditions were bad and I was afraid to disturb the mating with strong light, the pictures are quite unsharp.
The male probably decided that the piece of wood was too small, and walked backwards, dragging the female up a nearby pumice, to its left (turning about 90 degrees counter clock wise). The tugging and pushing started again, and from the look of it the male did most of the work.
I called Esme, who was not amused to be woken up around 2:50. But when I convinced her she had to come and have a look she did came, and in the end she was happy that I woke her up so she didn't miss this.
Because of this was all quite exciting to me, and I was trying to take pictures I didn't make notes at first. I started to make a few when the second dance was taking place. I observed that the male was stroking the sides of the female with his first pair of legs, quite fast (I guess about over 10 times a second). This stroking happened a few times, I didn't count. Shortly after such a stroking session I noticed that the male, moved his claws up and a bit more apart, while holding the claws of the female. He did this a few times in a slow, almost elegant movement. It's tail was stretched, and after the "handshaking" its tail moved slowly up and down, also in a slow wave like motion. When the male stopped doing this, the female stroked the male with the side of her tail on the back. The male tugged the female, walking backwards and then suddenly the two broke apart, each walking quite fast in different directions.
Other things I noticed, but can't remember exactly when it happened during the mating dance: the scorpions using their mouth parts like they were kissing, and the male moving the front part of his head on top of the front part of the female, which I guess is partly visible in the above picture.
I decided that after the breaking up it was the right time to remove the female from the terrarium, since the breaking apart and almost running away form each other suggested to me that if they would find each other again there would probably be no dancing.
I checked the piece of pumice on which the second dance occurred, and I did found a spermatophore (sperm package) roughly in the center of the stone.
During the dancing I also noticed that the female had a wet spot on her back, close to the start of the first tail segment, to the left side. This is not visible in the pictures. I am quite convinced that it was not on her back when I lifted the piece of pumice underneath which she was hiding. On the other hand, I had made the terrarium just wet before I uncovered the female.
Sadly I didn't measure the time of the above mating ritual, but I guess it was around 10 minutes in total.
The male scorpion in the above pictures measures from head to start of the first tail segment about 27 mm.