Sunday, August 31, 2014

The "Unbeetle" Beetle

© 2007 Beatriz Moisset
The distinguishing feature of all beetles is their hard external shell or coat. They don't seem to have wings. At least none are visible. The delicate, film-like wings of wasps and flies seem absent. But most beetles do have wings and fly quite well. The front wings of most insects have been modified in beetles into a hard case, called elytra, that covers and protects the second pair of wings. Their membranous hind wings remain out of sight, folded like origami. When they are ready to take off, the hinged hard elytra moves out of the way and the unfolded large hind wings are ready to go.

The exception to this rule is a peculiar insect without a common name and with just as peculiar a scientific name, Ripiphorus. In the case of this unusual insect the elytra are reduced to two little nubbins incapable of covering anything. The hind wings are longer than the beetles body, thin and translucent like those of wasps or flies. For lack of cover there is no point in folding them, so they are in plain sight all the time. I wouldn’t expect you to realize that it as a beetle if you are not an entomologist. I remembered being perplexed, myself the first time I saw one of these. You would probably ask: "Is that a wasp, or could it be some kind of fly?"

Male Ripiphorus beetle © 2011 Ilona Loser
 Some Ripiphorus are entirely black, others deep red. The males can be distinguished from the females by their flamboyant, feather-like antennae. Now, let us get back to its name and what it means. It should be spelled Rhipiphorus. Too bad the original author made a mistake and the rules of nomenclature prevent us from changing the original name. In Greek, it means a fan carrier, in reference to the male's impressive antennae. So, let this be its common name.

Female laying eggs. © 2007 Beatriz Moisset
You are more likely to see the females because they live a little longer than the males. They diligently visit flowers, not just any flowers, but only the fresher ones, the ones that are just beginning to open. They have a clever reason for doing this. They lay their eggs inside the blossoms and leave them to fend for themselves.

The newborn is not a defenseless shapeless grub like most beetle larvae. Instead it is mobile, with sharp claws, and can recognize a bee when it sees one. When a pollinator arrives at the flower, a few days later, the larva jumps into action and climbs into it. When the bee arrives at the nest with her load pollen and nectar, the little hitchhiker dismounts, ready to perpetrate its deed. Soon, it proceeds to feed on the bee's growing larvae and it may also consume some of the supplies. This is how a Rhipiphorus beetle makes a living, at the expense of an innocent pollinator's babies. Thus, it is considered a parasitoid, a word derived from parasite, but with a slightly different meaning. A parasite, ordinarily, doesn't kill its victim or host. The parasitoid behaves like a parasite at first but ultimately kills its host.

I feel sorry for the poor pollinator, but realize that this is the way of nature. I accept the behavior of this fascinating beetle and marvel at its strange looks and singular life style.

© 2007 Beatriz Moisset

List of articles
Beginners Guide to Pollinators and Other Flower Visitors

© Beatriz Moisset. 2014


  1. This is fascinating! I don't remember ever seeing one of these beetles, but if I had, I probably wouldn't have known what I was looking at. Checking the genus (and family) out at BugGuide, I notice that they are usually fairly small beetles, so I may not have felt I could photograph them well, so didn't pay enough attention. Something else cool to watch for!

    1. It doesn't seem to be very common. Look for it on flowers that are just beginning to open. July and August seem to be the best months.

  2. Wow..This is a wonderfully informative post.. I didn't know that...Michelle

  3. I love learning new things! Thank you for sharing this.