The Limacodidae or Eucleidae are a family of

moth Moths are a group of insects that includes all members of the order Lepidoptera that are not Butterfly, butterflies. They were previously classified as suborder Heterocera, but the group is Paraphyly, paraphyletic with respect to butterflies (s ...

s in the superfamily Zygaenoidea or the Cossoidea;Scoble, M.J. (1992). ''The Lepidoptera: Form, Function and Diversity.'' Oxford University Press. the placement is in dispute. They are often called slug moths because their

caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder ...

s bear a distinct resemblance to

slug Slug, or land slug, is a common name for any apparently shell-less Terrestrial mollusc, terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced ...

s. They are also called cup moths because of the shape of their cocoons. The larvae are often liberally covered in protective stinging hairs, and are mostly

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

, but occur worldwide, with about 1800 described species and probably many more as yet undescribed species.

Description

Moths

They are small, hairy moths, with reduced or absent mouthparts and fringed wings. They often perch with their

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

s sticking out at 90° from their thoraces and wings. North American moths are mostly cryptic browns, sometimes marked with white or green, but the hag moth mimics bees.Wagner, D.L. (2005). ''Caterpillars of Eastern North America.'' Princeton University Press.

Pupae

The final

instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...

constructs a silk cocoon and hardens it with calcium oxalate excreted from its

Malpighian tubules The Malpighian tubule system is a type of excretory and osmoregulation, osmoregulatory system found in some insects, myriapods, arachnids and tardigrades. It has also been described in some crustacean species, and is likely the same organ as the ...

. Cocoons have a circular escape hatch, formed from a line of weakness in the silk matrix. It is forced open just prior to emergence of the adult.Epstein, M.E. (1996). "Revision and phylogeny of the limacodid-group families, with evolutionary studies on slug caterpillars (Lepidoptera: Zygaenoidea)." ''Smithsonian Contributions to Zoology.'' No. 582. ISSN 0081-0282

Caterpillars

The larvae are typically very flattened, and instead of prolegs, they have suckers. The thoracic legs are reduced, but always present, and they move by rolling waves rather than walking with individual prolegs. They even use a

lubricant A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, ...

, a kind of liquefied

silk Silk is a natural fiber, natural protein fiber, some forms of which can be weaving, woven into textiles. The protein fiber of silk is composed mainly of fibroin and is most commonly produced by certain insect larvae to form cocoon (silk), c ...

, to move. Larvae might be confused with the similarly flattened larvae of lycaenid butterflies, but those caterpillars have prolegs, are always longer than they are wide, and are always densely covered in short or long

setae In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae ...

(hair-like bristles). The head is extended during feeding in the lycaenids, but remains covered in the Limacodidae. Many limacodid larvae are green and fairly smooth (e.g. yellow-shouldered slug), but others have tubercles with urticating hairs and may have bright warning colours. The sting can be quite potent,Marshall, S.A. (2006). ''Insects: Their natural history and diversity.'' Firefly Books. causing severe pain. The larval head is concealed under folds. First-

s skeletonise the leaf (avoiding small veins and eating mostly one surface), but later instars eat the whole leaf, usually from the underside. Many species seem to feed on several genera of host plants. Limacodidae larvae in temperate forests of eastern North America prefer glabrous leaves, presumably because the trichomes of pubescent leaves interfere with their movement.Lill, J.T., Marquis, R.J., Forkner, R.E., Le Corff, J., Holmberg, N., & Barber, N.A. (2006). "Leaf pubescent affects distribution and abundance of generalist slug caterpillars (Lepidoptera: Limacodidae)." ''Environmental Entomology'' 35(3): 797–806. ISSN 0046-225X Image:PhobUnderside.JPG, Underside of a monkey slug, showing the slimy pad in place of prolegs Image:Lithacodes.JPG, Larva of the yellow-shouldered slug, showing typical body shape Image:Cup moth caterpillar.jpg, '' Doratifera'' larva, showing bright colours and presumably stinging setae Image:Saddleback (Sibine stimulea).jpg, ''Sibine stimulea'' ( saddleback caterpillar) larva File:Parasa pastoralis caterpillar.jpg, Larva of '' Parasa pastoralis'' Image:Stinging_Rose_caterpillars,_Megan_McCarty65.jpg, Stinging rose caterpillars ('' Parasa indetermina'') Image:Richters wurm.JPG, Limacodid larva File:Limacodidae (Slug moths) caterpillar W IMG 2795.jpg, Limacodid (slug moth) caterpillar Slug moth caterpillar (Limacodidae sp.).jpg, Slug moth caterpillar,

Sabah Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah has land borders with the Malaysian state of Sarawak to the southwest and Indonesia's North Kalima ...

, Borneo

Eggs

Eggs are flattened and thin. They are highly transparent and the larva can be seen developing inside. They may be laid singly or in clusters on leaves.

Ecological importance

Limacodidae (e.g. '' Latoia viridissima'', '' Parasa lepida'', '' Penthocrates meyrick'', '' Aarodia nana'') have caused serious

defoliation A defoliant is any Herbicide, herbicidal chemical sprayed or dusted on plants to cause their Leaf, leaves to fall off. Defoliants are widely used for the selective removal of weeds in managing croplands and lawns. Worldwide use of defoliants, ...

of palms.

Notable species

* Hag moth or monkey slug ('' Phobetron pithecium'') * Ochre-winged hag moth or yellow-shouldered slug ('' Lithacodes fasciola'') * Spiny oak slug ('' Euclea delphinii'') * Crowned slug ('' Isa textula'') * Skiff moth ('' Prolimacodes badia'') * Nettle caterpillar ('' Latoia viridissima'') * Saddleback caterpillar ('' Acharia stimulea'')

References

External links

*

Brisbane Limacodids, with photo of cocoon.

Moths of Borneo {{Authority control Limacodidae, Moth families