The largest P. ciliata grow to around 95 mm - just under 4 inches. It is rare that you can find one that large and ever rarer that they would obtain that size in an aquarium.
The only other large spearer that occasionally shows up in the Indo-Pacific trade is Lysiosquillina maculata. The largest individual of this species ever recorded was just under 40 cm - a little over 15 inches. The largest I have ever collected was 33 cm. The ones I have seen for sale are usually in the 7 - 9 inch range. If you plan to keep one until it reaches a really large size, you will have a long wait. They live for at least 20 years and large individual rarely exhibit much growth in an aquarium. In fact, they often shrink. I have one that was captured about 5 years ago that was about 24 cm and it is still that size.
Part of the problem with their growth in an aquarium may relate to their burrow. In the field, the burrow would be a large u-shaped tube several feet long. The entrances are vertical about 1.5 times the length of the animals, then run horizontal under the surface of the sand. They are also monogamous. Large females are rarely caught. THey also have smaller raptorial appendages than males and rarely hunt for themselves.
No worries about glass breaking. The very largest males might be able to break thin glass, but they rarely strike and I have never seen it happen. On the other hand, some of the worst wounds i have ever gotten from stomatopods came from Lysiosquillina, so it pays to be careful when handling them. I should also add that this species is one of the most popular species sold as food. In Tahiti they are called Varo and bring $50 or more in the market. Unfortunately, they are so popular that they have been fished out of local waters and now are typically brought in from the Tuamotus. They still can be found in Hawaii and are abundant in much of the rest of the Indo-Pacific.
I don't know if you can special order them from importers, but in the trade they are often called the banded or zebra mantis.
Roy
