4 (also monitor lizard) A large tropical Old World lizard with a long neck, narrow head, forked tongue, strong claws, and a short body. Monitors were formerly believed to give warning of crocodiles.Called goanna in Australia. (also monitor lizard) A large tropical Old World lizard with a long neck, narrow head, forked tongue, strong claws, and a short body. Monitors were formerly believed to give warning of crocodiles.
The most effective way to prevent black toenails is to run in shoes that fit properly. You should have a thumbnails width room between your big toe and the front of your shoe while standing, not sitting. You should also wear moisture thin, moisture wicking socks to prevent increased heat build-up.
Simply put, black toenails are caused by improperly fitted running shoes. All running shoes should have one thumbnail's length from the tip of your longest toe (and in some that means the second toe) to the end of the shoe. Don't worry about the shoe size number because most of us need running shoes a full size or larger than the number of our normal shoe size.