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Not all heroes wear capes! Quicksilver ants are named for their remarkable ability to beat the extreme heat of the Saharan desert. Workers have a thin coat of special silver hairs which can reflect sunlight and radiate excess heat away from their bodies. They also spend as little time outside the nest as possible, which means they travel fast; individuals have been clocked at moving 108 times their body length in a second, reaching speeds of up to 3.1 kph (1.9 mph). That makes it the fastest known species of ant!

Above: Carriola witti

Moths of the genus Carriola have a very unusual appearance, as their wings are covered in translucent patches that reveal a delicate network of greenish-yellow veins. The green coloration is caused by the haemolymph (i.e. "blood") that passes through these veins.

Above: the male form of Carriola thyridophora, with a close-up of the hyaline windows and bright green veins on its wings

The males of this genus typically have brown or beige borders around their wings, while the females have pink or white borders instead. The hyaline windows also tend to be much clearer and more extensive in the females.

Above: the female form of Carriola seminsula

This article describes the adaptive benefits of wing transparency in moths:

The coevolutionary arms race between prey and predator has generated some of the most striking adaptations in the living world, including lures, mimicry and camouflage in prey. Transparency, by definition, constitutes the perfect background matching against virtually all types of backgrounds. Transparency is common in pelagic environments where there is no place to hide.

Above: genus Carriola

Carriola tussock moths can be found in many different countries throughout Southeast Asia, including Indonesia, Singapore, Thailand, Laos, Myanmar, the Philippines and Malaysia. They also inhabit certain parts of China, India and Sri Lanka.

Above: Carriola seminsula

This is one of my favorite moths, tbh. I love it when moths have hyaline windows on their wings, and this genus is especially beautiful and bizarre.

Sources & More Info:

Nota Lepidopterologica: Review of the Genus Carriola with Descriptions of Four New Species

Singapore Biodiversity: Carriola ecnomoda

iNaturalist: Genus Carriola

BioRxiv: How Transparent Wing Windows Reduce Detectability in Moths

Journal of Evolutionary Biology: Transparency Improves Concealment in Cryptically Colored Moths (PDF)

Moths of Borneo: Carriola Tussock Moths

Pink crab spider, Thomisus onustus, Thomisidae

Found throughout Europe and into northern Africa and Asia

Mymaridae is a diverse family of wasps that contains more than 1,400 known species, and they're often described as fairy wasps (or "fairy flies") because they are so incredibly tiny. In fact, these are some of the smallest multicellular animals ever described, with most fairy wasps measuring less than 1mm long.

Above: a species of fairy wasp, Lymaenon aureus, depicted on a lime

One species of fairy wasp, Dicopomorpha echmepterygis, is regarded as the world's smallest known insect, measuring as little as 0.139mm (139 microns) long, which is roughly the size of a single human egg.

Above: Anagrus fairy wasp

As this article explains:

Fairyflies are not actual flies at all, but chalcid wasps; they get their name because of their fairy-like wings, and for being tiny and "invisible" like the mythical fairies. Fairyflies have the smallest known adult form of any insect: wingless and blind males of the species Dicopomorpha echmepterygis have a body length of just 0.139 mm, about the average width of a human hair. The fairyfly family Mymaridae consists of many species, including Tinkerbella nana and Kikiki huna, the smallest known flying insect species with a body length of 0.16 mm.

Above: the photo at the top shows a fairy wasp of the genus Anagrus, while the photo on the bottom shows another species from genus Polynema

Most fairy wasps have fully-functional wings that are lined with long, feathery bristles:

Fairyfly wings are not only small, but their structure is comb-like and made of several bristles instead of a planar sheet. Their very small size means that the air around them is more viscous than it would be for larger insects. At such small scale, the ratio of inertia to viscosity, the Reynolds number, is so low that any movement provided to an air packet quickly dampens out. It also means that a single wing bristle drags along with it a boundary layer of a comparable size. Thus, if the bristles are sufficiently close, the comb-like wing can act as a paddle to generate the requisite aerodynamic forces, while reducing the overall mass of the wing.

Above: a fairy wasp depicted beneath a push-pin

All of the wasps in this family are parasitoids, and they lay their own eggs within the eggs of other insects. They often parasitize the eggs of booklice, aphids, scale insects, thrips, water beetles, and other tiny arthropods. The female fairy wasp inserts her ovipositor into the host egg, depositing her own offspring within, and the process is then repeated many more times as she parasitizes as many eggs as possible.

Above: this composite image shows male and female fairy wasps of the genus Polynema standing on a pinhead

This seems like a good time to point out that fairy wasps do not parasitize mammalian ova, nor do they parasitize the eggs of any other vertebrates, and they are completely harmless to humans. In fact, they're actually beneficial, since they often parasitize agricultural pests.

Above: a fairy wasp trapped in a tiny guttation drop produced by a fungus

I posted some information about fairy bees a few weeks ago, so I figured that I should share these little fairy wasps, too.

Above: a Mymar fairy wasp with an aphid standing nearby

Sources & More Info:

Current Biology: Fairyflies

Annual Review of Entomology: Small is Beautiful: Features of the Smallest Insects and Limits to Miniaturization (PDF)

Journal of Hymenoptera Research: A New Genus and Species of Fairyfly, Tinkerbella nana, with Comments on its Sister Genus Kikiki, and Discussion on Small Size Limits in Arthropods (PDF)

Broad-nosed weevil, Exophthalmus sp., Curculionidae

Wasps of the genus Baeus are sometimes described as "micro-flea wasps," because the females of this genus have tiny, rounded bodies that measure just 0.8mm long.

Above: a female Baeus wasp compared to the tip of a pencil

As this article describes:

Baeus represents one of the most unusual genera of parasitic wasps in that females are apparently wingless, highly compact and flea-like in appearance. They are endoparasitoids of spider eggs of host families associated with above-ground vegetation and crytobiotic niches such as leaf-litter.

Above: female Baeus wasps

The wasps often ride around on the backs of female spiders, simply waiting to parasitize the spiders' eggs:

They have a hypodermic-like ovipositor that is used to pierce the chorion of a host egg, in which they lay their own egg. The [wasp] larva then consumes the contents of the host egg, pupates within it, and emerges as a fully developed adult.

Above: a female Baeus wasp clinging to the underside of a cellar spider's eggsac

This genus remains poorly studied, with only 25 species currently described world-wide:

Even though the highly unusual nature of Baeus has been known for over 170 years, only 25 species have been described to date, three from Australia, seven from the Nearctic, six each from the Neotropics and the Palaearctic, one each from the Oriental and Afrotropical (Seychelles) regions, and one from Hawaii. However, significant numbers of species occur in many regions, particularly in the wet tropics, subtropics and southern hemisphere temperate forests.

Above: a Baeus wasp depicted next to a 0.7mm mechanical pencil lead

These may be the world's most adorable wasps.

Above: a female Baeus wasp grooming herself

Sources & More Info:

Zootaxa: Systematics, Distribution and Biology of the Australian "Micro-Flea" Wasps

iNaturalist: Genus Baeus

Impact Journals: Incidence of Egg Parasitism in Argiopepulchella

Bulletin of the Southern California Academy of Sciences: The Black Widow Spider and its Parasites