The Mark of the Dragonfly by Jaleigh Johnson

This book is a 2014 release, and I gave it a rating of five out of five. Piper lives in a town where the people make money by scavenging around craters after meteor storms. She sees a huge meteor smash into a trade caravan and rescues a small girl, Anna, from the wreckage. Anna has a tattoo on her arm, the mark of the dragonfly, which means she's under the king's protection. However, Anna can't remember anything about the tattoo or her past, but she's terribly afraid when another survivor from the caravan shows up at Piper's door. The girls climb aboard a cargo train and head to the capital city, hoping to find Anna's family. They don't realize that Gee, head of train security, is also the green creature they've seen flying in the sky. Trouble is on the way when Doloman, the king's head mechanic, discovers the girls are on the train. Secrets about Piper and Anna will be revealed, but will the secrets lead them to disaster or to their freedom?

I really enjoyed Anna and Piper. The author dropped hints about Piper's power over machines, and Anna was too wise for a small girl. The setting was mostly on the train, which is rather unusual for middle-grade fiction. The plot mixed in periods of action and adventure, but questions surrounding Anna's past gave it the feel of a mystery.