Corrected entry: When Brett's biker friend is attacked, he is tackled from the front, yet in the next shot the spider has him pinned on his back.
Corrected entry: At several points where town's folk are being chased in the mine, Chris mentions that the smallest spark will cause a devastating explosion. He then proceeds to take the motorcycle to rescue his aunt, and then starts the bike for a quick escape. As soon as the bike starts, they'd all be dead as a spark is needed to ignite the petrol, which would also ignite the methane gas.
Corrected entry: In one of the scenes where Chris and Aunt Gladys are seen riding through the mine they are shown exiting it, but after cutting to a different scene they are shown again still riding through the mine and not at the exit yet.
Corrected entry: When the spider farm guy is bitten near the beginning of the film, there are spiders running all over the ceiling before he bangs into any of the spider cases and knocks them over.
Corrected entry: At the end, all the spiders are supposedly killed in the explosion, but what about all the trapdoor spiders? They are all underground in the car park and the ostrich farm! They wouldn't have been killed in the explosion.
Corrected entry: When the sheriff's deputy arrives to pick up the sheriff and her family, the spiders start jumping onto the roof as they are leaving. The female sheriff then turns around and shoots one of the spiders with a shotgun. The problem is, the distance she is, I doubt the shotgun would do the kind of damage it did.
Corrected entry: The tunnels are full of methane gas - no smoking or it will blow. However, you can ride around in the tunnels all day on a motorcycle powered by an internal combustion engine and not explode the gas.
Corrected entry: When the mine is exploding near the end, David Arquette says "Goodbye Consuela" (or something to that extent) as he rides out with the giant spider in flames behind him. However, only Mike and the spider shack keeper knew the spider's name. It was mentioned in the beginning of the movie but never said anywhere else.