Adult moths usually obtain their food from nectar and other sources of proteins and minerals, but there is one species with a rather gruesome habit: Calyptra thalictri is a very ordinary-looking pale brown moth from the family Noctuidae.

It is a native of Malaysia, the Urals and southern Europe but has recently been recorded in Finland and Sweden, and could soon find its way to Britain. Like other moths it has a proboscis constructed from 2 hollow tubes which are used like a straw to suck fluids. Instead of feeding at nectar, the Vampire moth feeds on blood by drilling its proboscis into the skin of mammals including humans!

There is no known health risk, but the wound can remain sore for a couple of hours. The vampire habit probably evolved from an ancestral ability to pierce fruit, but it could have arisen accidentally when moths imbibed mammal sweat – in the tropics many butterfly species and moths habitually obtain essential minerals by imbibing human sweat.

The chrysalis that sings !

The caterpillar of the Green Hairstreak Callophrys rubi leaves the foodplant to pupate just under the surface of the ground, often where there are stones or fallen leaves. The pupa has the ability to produce a squeaking noise – this was once thought to be a defence mechanism against ants and beetles, but research on other Lycaenids that also share this behaviour suggest that the pupa is actually “singing” to attract the attention of ants, which carry it into their nests below the ground.

The pupa secretes a sugary substance which the ants drink. In exchange the pupa gains protection from other insects that would not dare enter the ants nest.

The Green Hairstreak Callophrys rubi, has a chrysalis that sings! © Adrian Hoskins

Hitch-hiking on butterflies !

Close examination of recently emerged butterflies can sometimes reveal the presence of very tiny scorpion-like creatures clinging by their pincers to the legs or antennae. These “pseudoscorpions” are carnivores. They normally feed on mites, insect eggs and young larvae. They don’t feed on the adult butterflies or harm them in any way – they simply hitch a lift on them, using them as transport to enable them to disperse to new habitats.

One tactic they use is to ambush a fully grown larva, using their powerful pincers to grab hold of it by its spines or head horns. When the pincers bite, the pseudoscorpion becomes quiescent. After a few hours the larva pupates.

The pseudoscorpion remains attached to the shed larval skin, which itself remains attached to the base of the pupa. Eventually the butterfly emerges from the pupa and the pseudoscorpion then scuttles onboard the butterfly, gripping hold of its antennae or legs. The butterfly then flies off. Sometime later when it lands in a suitable place, perhaps several kilometres away, the pseudoscorpion drops off. Pseudoscorpions are related to spiders, mites, scorpions and harvestmen. Their hitch-hiking behaviour is known as phoresy.

Amphibious, carnivorous caterpillars !

Scientists have discovered the first known truly amphibious insects – 4 species of moth in the genus Hyposmocoma ( Cosmopterigidae ) are now known to be capable of completing their entire larval period either on land or under water.

The larvae are found only on Hawaii. They normally live in damp habitats on land, but are equally at home in fast running streams, at which time they breathe by direct diffusion of oxygen through hydrophilic skin. They live within conical or cylindrical cases, very similar to those used by caddis fly larvae, and constructed by binding together tiny fragments of wood or gravel with silk.

The feeding behaviour of the larvae is unique among Lepidoptera – most of the 350 members of the genus Hyposmocoma feed on plants, but these 4 species are carnivorous. They seize small snails and other molluscs, bind them with silk to prevent them escaping, and then devour their soft tissue!

Hyposmocoma are the only known species to feed on molluscs, although various other forms of carnivorous behaviour are found among certain families of butterfly and moth. The larvae of many species of Blues and Hairstreaks ( Lycaenidae ) for example feed on ant grubs or aphids.

In Peru, the eggs of Caligo butterflies are parasitised by tiny Trichogrammatid wasps that ride from place to place on the hindwings of the butterflies. They only leave the female’s wings when she lays eggs, and then immediately return, to be transported by the butterfly to the next egg laying site.

Owl butterfly Caligo teucer, Peru – Adrian Hoskins

Scary eyes to frighten birds !

Many butterflies, such as the Peacock Inachis io are marked with conspicuous ocelli ( false eyes ) which can scare off a predator, or at least deter it long enough for the butterfly to make it’s escape. The ocelli make the butterfly appear larger and “scarier” to predators, and in many cases have the effect of simulating the face of a small mammal or reptile.

Peacock Inachis io, male, Broughton Down, Hampshire – Adrian Hoskins

Butterflies with strange names !

The popular names given to butterflies are often fascinating. Here are a few of my favourites :

The Charismatic Metalmarks

Taxonomists are not usually renowned for having a great sense of humour, but amongst their more hilarious moments they have managed to provide us with a few amusing scientific names. Hence we have a pair of metalmarks from Colombia, named by Hall and Harvey in 2002 as Charis ma and Charis matic !

Both have since been renamed less attractively as Detritivora ma and Detritivora matic. The new genus name refers to the fact that the caterpillars feed on decaying leaves and other detritus on the forest floor.

The Mediocre Skipper !

It must be difficult to think up names for some of the more mundane looking species, particularly for the hundreds of near-identical dull brown skippers found in the neotropics. In 1997 Austin was apparently so unimpressed with one Mexican discovery that he gave it the unfortunate name of Inglorius mediocris, which needs little translation !

More “creative” scientific names…

The taxonomist Burns was clearly having a mental block when it came to naming his new skipper – Cephise nuspesez ( pronounced “new species” ) !

Just to prove that weird humour is not confined to butterfly taxonomists ( ! ), here are some of the equally odd scientific names given to other creatures – these are genuine species names !

The above show both creativity and humour, but in 1969 when Spencer had the task of inventing names for new flies he just named them in numerical order, hence : Ophiomyia prima, O. secunda, O. tertia, O. quarta, O. quinta, O. sexta, O. septima ( Latin for “first”, “second”, “third”, etc. ).They don’t always get away with it though. Common sense prevailed when Dybowski proposed the name Gammaracanthuskytodermogammarus loricatobaicalensis for a new Amphipod in 1927. It would have been the world’s longest scientific name, but was rejected as unpronounceable by the International Commission for Zoological Nomenclature !

The honour of having the longest scientific name approved by the ICZN actually goes to a species of Stratiomyid fly – Parastratiosphecomyia stratiosphecomyioides, while the shortest appears to be that of a Vespertilionid bat – Ia io, although there is a thrip with a single-letter species name – Plesiothrips o.

Caterpillars come in some strange shapes, but there can be few creatures more weird-looking than this bizarre Euphobetron moth larva ( Limacodidae ) from French Guiana. The photo does not depict a group of larvae – it is a single larva with enormous hairy limb-like lateral extensions!

Euphobetron aquapennis larva, French Guyana – Stéphane BRÛLÉ

Plants that trick butterflies !

Caterpillars of Cattle Heart butterflies ( Parides ) from South America feed on Aristolochia vines, but some vines can defend themselves by only “permitting” the butterflies to lay a small number of eggs. If extra eggs are laid, the leaf around the egg dies, and the dead tissue drops to the ground, carrying the egg with it ! A similar trick is played by Passiflora vines, which produce stipules at the base of leaf stems, that induce egg laying by some species of Heliconiine butterflies. A day or two later the stipules drop off, carrying the eggs with them.

Some other Passiflora vines produce tiny tubercles on the stipules that mimic Heliconiine eggs. Any butterfly visiting the plant sees the false eggs and is misled into thinking that the plant is already overladen with eggs, so is inhibited from adding more.

Heliconius erato, Rio Madre de Dios, Peru – Adrian Hoskins

Wings with ears !

Some butterflies can detect sound, using “ears” on the underside of their wings. These microscopic funnel-shaped ears are covered with a thin membrane that vibrates in response to high frequency sound. The ear is only present in certain butterfly families. Some scientists believe that all early butterflies were nocturnal, and that the ears evolved to enable them to detect and avoid predatory bats. Other butterfly families which do not possess ears are thought to have evolved daytime flight as an alternative anti-bat strategy.

Caterpillar cannibals !

Caterpillars of the Scarce Swallowtail Iphiclides podalirius are territorial. The silk trails which they lay as they walk along twigs have a slight odour. This enables each larva to recognise it’s own silk trail, and use it as a route map to find it’s way back to particularly succulent leaves. If two larvae meet, the larger one spins a silk web around the smaller one to kill it, or bites it to death.

Epiphile caterpillars in South America are equipped with long sharp poisonous “antlers” which they use to defend themselves against other insects. If disturbed they swish their heads violently, using the antlers to puncture the skin of attacking insects. The lepidopterist Muyshondt observed Epiphile caterpillars attacking each other, locking antlers until death.

Headless butterflies can still fly !

In June 2010, when in the Peruvian Andes I chanced upon a group of Diaethria butterflies settled on the ground. Most were busily imbibing mineralised moisture from the damp sand. One particular butterfly however was walking about, slowly fanning its wings. I crept closer in order to photograph it, and peering through the camera viewfinder I suddenly realised that the butterfly had no head! Despite having been decapitated ( following an attack by a bird or a wasp? ) it was perfectly able to walk, fan its wings and even to fly short distances!

The explanation is that insects have a nervous system in which certain functions are not centralised on the brain. Hence reproduction, locomotion and respiration are not dependent upon retaining a head. This not only explains why a headless Diaethria can walk and fly, it also explains how a male praying mantis can complete a sequence of mating processes with a female while she is eating his head ! This incidentally is normal behaviour for mantises – males passively submit to cannibalism, a practice that may have evolved because copulation duration and fertilisation success are almost doubled when the male is cannibalised.

Diaethria clymena  – walking and fanning its wings after decapitation, Shima, Peru – Adrian Hoskins

Intelligent butterflies !

The seemingly complex courtship rituals of many butterflies implies that they have some degree of intelligence, but careful analysis shows that the rituals are merely a series of instinctive responses to specific stimuli. A female for example might react in a certain way if approached by a male and showered with pheromones, but the male then also has to respond in a particular way which signals the female to initiate the next stage in the ritual, and so on.

However there is some evidence that certain butterflies do demonstrate intelligence and reasoning. Experiments have proven that Heliconius butterflies can learn home ranges within which they can memorise the locations of nectar and pollen sources, host plants and communal roosting sites. They are able to plan the most efficient route by which to visit all nectar / pollen sources in the vicinity by using simple calculations akin to what mathematicians call the “travelling salesman algorithm”.