Jewel Caterpillars

Not much is known about so-called Jewel Caterpillars of the genus Dalceridae but one thing’s certain: this group of 84 moth species includes some of the most beautiful bugs you’ve ever laid eyes on. Like gorgeous gems, however, it’s better to look than to touch: the soft, sticky, slug-like creatures are a treat for the eyes, not the hands.

Meet Acraga Coa, A “Slug” With Style

Though caterpillars and moths of the genus Dalceridae have been described in scientific literature for over a century, it’s only recently that they’ve come to wider notice among regular folks. This is partly due to the creatures’ habitat, typically tropical rainforests of the Neotropic ecozone which stretches from southern Florida and coastal Mexico down through most of South America.

While advances in modern photography have helped expose Dalceridae larva to readers of National Geographic magazine, among other such publications, the recent proliferation of news blogs, science websites, and photo-sharing sites like Flickr and Pinterest have done even more to bring Jewel Caterpillars to a wider audience.

Beautiful though the Dalceridae may be, just what the heck are they? Among a vast wealth of caterpillars of virtually all shapes, sizes, colors and configurations, Jewel Caterpillars stand out from the crowd. Even those species whose larvae are uncolored rivet one’s attention due to their glossy gelatinous coatings that seemingly transform them into living, moving gems.

The spotlight shining on Dalceridae larvae will likely solidify their everyday colloquial name from Slug Caterpillars to Jewel Caterpillars. Nothing against slugs – some species are surprisingly brightly colored – but for the Dalceridae looking astonishingly exquisite is the norm and not the exception.

The particular Jewel Caterpillar featured here is the larva of Acraga Coa, a moth native to the Mexican rainforest. Its rise to Internet stardom was facilitated by Gerardo Aizpuru, a scuba instructor and amateur wildlife photographer who noticed a specimen crawling across a Mangrove tree leaf near Cancun, Mexico, one day in April 2012. Aizpuru submitted his excellent snaps to Project Noah, user-created image and knowledge database self-described as “a tool to explore and document wildlife and a platform to harness the power of citizen scientists everywhere.”

Diamonds In The Rough

Over the next days and weeks, Aizpuru’s lovely “living jewel” exploded across the Web with lightning speed, prompting a flood of search inquiries asking what the creature was and were there others similar to it.

At this point the spotlight shifted somewhat as amateur and professional photographers alike searched online databases and actual rainforest habitats for other members of the Dalceridae family. Could any of Acraga Coa’s cousins rival its larva’s striking good looks?

Jewel-like but not gems, Dalceridae larvae such as the specimen above look good enough to pin to one’s blouse though that’s not recommended. In fact, they may look the way they do by design: predatory ants and insects display a distinct distaste for the caterpillars’ gooey, gelatinous coverings.

It seems as if the caterpillars are well aware of their power to give potential predators pause. They’ve been observed crawling on top of leaves, resting in full view of all and sundry, nonchalantly showing off their glistening coats and apparently daring any enemies to take a bite – and very few do.

It’s hard to get a handle on which Dalceridae caterpillar is which. Not that entomologists are “sluggish” in any way, it’s just that the combination of the creatures’ hard to reach habitats and the fact that many caterpillars look different from one molt to another make identifying any one Dalceridae larva a bit of a guessing game.

Than again, what’s in a name? For non-scientists who don’t have to submit a thesis, simply enjoying the wonders of nature as expressed by Jewel Caterpillars is enough of a blessing. Take the lime green critter above: could it hold a candle to an emerald or vice versa? Let’s not try holding candles to emeralds or Jewel Caterpillars, okay?

Orange You Glad It’s A Moth?

Every caterpillar is destined to become a moth, assuming it survives the many trials and tribulations of the larval state and manages to make with the metamorphosis inside its cocoon. For Jewel Caterpillars, this stage of life remains wrapped in mystery. Until science shows us otherwise, we’ll have to imagine Dalceridae larvae weave cocoons similar to the Urodus (possibly) moth’s gorgeous golden basket above.

Everyone knows the story of the ugly caterpillar reborn as a beautiful butterfly, and while moths are often lacking in the beauty department Acraga Coa doesn’t disappoint. Not only is the moth Painted a warm, rich shade of orange, it’s festooned with fluffy tufts worthy of the Westminster Dog Show’s prettiest poodle.

Glutinous gooey gel and fluffy filamentary fur – polar opposites to be sure but the exquisite Jewel Caterpillar manages to transform one into the other without even the most minor of missteps. It’s just one more example of Nature’s wonder, honed to perfection over many millions of years of evolution with, perhaps, millions of years of further refinement to look forward to!