If you have palm trees around you house, they are probably residing in the trees. They are very big and you can hear them scurry up the trees and around in the bark. These types of cockroaches don't generally try to get into your house and they aren't a reflection of how clean you keep your living quarters. If you have palm trees and therefore Palm Cockroaches, the best thing to do is keep debris away from the house (like bark mulch...they will burrow into that stuff. Get some rock mulch) and make sure palm trees have the old, dead fronds that are brown and hanging down removed (the cockroaches make home in those dead fronds). And if you can afford it, have the palms 'shaved', but that would have to be done professionally, but looks really nice!). I lived in Corpus Christi, TX for 7 years so I am familiar with your concern. Below are two links to pictures of a palm tree, one before shaving and defronding, the other after it was done.

tropical species are usually very large cockroaches, the humidty allows the insect to consume more organism.

Central America has the biggest one. It is more humid there.

We live in hot not humid climate.I before lived in Southern Europe but didn't see such a huge enormous monsters.I haven't actually seen it here since is dessert climate up to that moment!I opened the lights in my room and yukkkkk!Huge hairy brown cockroach hanging out on the wall having a good time,didn't even run for it's life when I opened the light.I never eat in my room or bring drinks.I vacuum every day and change sheets.The problem is there are some cracks in the wall around the airconditioner.They seem enough for her to enter.The other thing is that when people come from outside with groceries.Also there is little insulation on the outside door,has some space underneed.But I always keep religiously clean and also never saw one for 2 years.As I said my room is far from the kitchen.And even in the kitchen didn't see one.It's kind of tropical here or subtropical because is dessert and dry like hell with 110 farenhet .My washed clothes dry for 15 min when I put them in non airconditioned area.I don't have special cover for the drains,maybe thats why she came?I killed her but wow,,what a biggie!