Mangrove is a male RainWing who is featured in The Hidden Kingdom. He and his mate, Orchid, were fruit gatherers for the tribe. They were out gathering fruit when Orchid was captured by the NightWings. He first appears outside Queen Magnificent's tree house, waiting in line to protest about the missing RainWings. He volunteers Glory to search for the missing RainWings. He appears to be very affectionate of Orchid - a trait described by the author very rarely - as he constantly endeavoured to search for her. When not displaying a particular emotion, his scales seem to be a shade of dark purple.
After Orchid went missing, Mangrove was heartbroken and was quite determined to find her. He stood in line at Queen Magnificent's palace every day, waiting for his turn to tell the queen about the disappearances. Because of this he often missed portions of his suntime and was often grouchier than normal similar to Chameleon and Glory When it became apparent Magnificent wasn't going to do anything about it, he volunteered to help Glory in looking for the "rainforest monster". The search lead to the discovery of a portal that lead to the borders of the Kingdom of Sand and the hidden NightWing Kingdom. Thinking Orchid might be in the latter, Mangrove took off while the dragonets weren't looking.
Glory and Jambu then disguised themselves as IceWings and found him hiding in Blaze's Fortress near the IceWing palace, camouflaged against the sand in Blaze's room. They rescued him, but not before running into Deathbringer.
During the competition in which Glory tried to become queen, Glory picked Mangrove as part of her team. He participated in the fruit gathering contest and collected seventeen different fruits (including one that appeared to be newly discovered), beating Queen Dazzling, who originally had nineteen (through cheating by preparing beforehand), but ate three on the way back.
Starflight and Glory led an attack on the NightWings through the tunnel. There, they rescued Splendor, Orchid, the rest of the missing RainWings, and Deathbringer. Mangrove and Orchid reunited by locking tails.
Starflight mentioned that he was feeling a rumbling in the earth, and Mangrove replied that it was like "all the happiness in us is trying to burst out". After that he goes off with Orchid back to the rainforest.
Mangrove appeared when tasked along with Jambu to enter the Ice Kingdom, disguised as IceWings, to send a message to Blaze. When he returns, he and Jambu tell Glory that Blaze is not coming, and Mangrove says that it is because they know that Burn and Blister can both kill Blaze easily.
Unlike the average RainWing, Mangrove is shown to be rather alert, irritable, and perceptive, and noticed RainWings disappearing. This may be because he had neglected his suntime after Orchid went missing.
"I'll try...for Orchid."
"Complaining about something! I'll say! Something we should all be complaining about! My Orchid isn't the only one who's missing, you know!"
- Glory seems to trust Mangrove more than most of the other RainWings, most likely because he is more alert and not as lazy as most RainWings.
- It was stated he is grumpier than most RainWings, mainly because he missed a lot of suntime. This was after Orchid disappeared, and he spent his time worrying about her.
- Mangroves are salt-tolerant trees, referencing how he was "salty" as in the slang term for grouchy. The trees grow in swamps and wetlands.