Meganulon

Swarm life
The Swarm usually starts from one large egg that houses thousands, possibly tens of thousands, of eggs. They then hatch into the larval form, the Meganulon. After eating enough food they shed their skin and become the imago form, the Meganula. This form flies far away and lays another egg, starting the process all over again. Although the Meganulon and Meganula do most of the work, they must have a queen. So the Meganula begin to gather energy and deliver it to the chosen Meganulon. The Meganulon will absorb the energy and grow into the cocoon form of a Megaguirus. After absorbing enough energy the cocoon will burst open and reveal a Megaguirus.

Rodan
Meganulon (メガヌロン, Meganuron?) were Mesozoic giant insects reanimated by mining operations in Kitamatsu village, Kumamoto Prefecture, in the 1956 kaiju film Rodan. (Presumably they are, like the titular daikaiju, from the Cretaceous Period.) The car-sized insects, which resembled overgrown earwigs, slaughtered several men before some were killed in a mine shaft. A mine collapse followed, separating engineer Shigeru from fellow miners and police. Before finding his way out of the mine, Shigeru witnessed the hatching of Rodan, who began to devour the comparatively tiny Meganulon.

Godzilla vs. Megaguirus
The 2000 Godzilla film Godzilla vs. Megaguirus featured Megaguirus (メガギラス, Megagirasu?), an extinct species of dragonfly, based on the Meganulon, as Godzilla's adversary. According to the film, Meganula (also Meganuera) and Megaguirus had originated in China during Carbiniforous times. The insects follow an odonatan life cycle of which the Meganulon is the nymph stage. After a hemimetabolic interim the winged Meganula moult and take flight. Megaguirus was in fact the chosen queen among the colony and allowed to grow to massive size. As such, she is one of few decidedly female creatures of the genre.

Megaguirus's decendant was created when a weapon that would send Godzilla into a black hole created a time-space distortion. This allowed a Meganula from Earth's distant past to arrive on Earth and lay an egg which would later be discovered by a young boy and then hatch into a Meganulon. Megaguirus has numerous abilities. At top flight speed she vanishes into a blur, enabling her to surprise an opponent from an unexpected quarter. This high-speed flight also produces high frequency sonic waves capable of shorting out nearby electrical equipment. Her sharp wings can even cut steel and concrete. Her large abdomen ends in a vicious stinger used to pierce into an opponents hide and drain energy from it. During this process, the opponent is incapable of launching any additional energy-based attacks upon her.

Trivia
The Meganulon is an actual species of giant dragonfly that lived durring the Devonian Period nearly 300 million years ago. Of course, the real Meganulon never reached the size of the monster that appeared in Rodan or Godzilla vs. Megaguirus.