The Limacodidae or Eucleidae are a family of
moth
Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of ...
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
caterpillars bear a distinct resemblance to
slugs.
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. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
, 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 belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the tors ...
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 bee
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyly, monophyletic lineage within the ...
s.[Wagner, D.L. (2005). ''Caterpillars of Eastern North America.'' Princeton University Press. ]
Pupae
The final instar constructs a silk cocoon and hardens it with calcium oxalate excreted from its Malpighian tubules. 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 kind of liquefied silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the ...
, to move.
Larvae might be confused with the similarly flattened larvae of lycaenid
Lycaenidae is the second-largest family of butterflies (behind Nymphalidae, brush-footed butterflies), with over 6,000 species worldwide, whose members are also called gossamer-winged butterflies. They constitute about 30% of the known butterfl ...
butterflies, but those caterpillars have prolegs, are always longer than they are wide, and are always densely covered in short or long setae (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 hair
Urticating hairs or urticating bristles are one of the primary defense mechanisms used by numerous plants, almost all New World tarantulas, and various lepidopteran caterpillars. ''Urtica'' is Latin for "nettle" (stinging nettles are in the gen ...
s 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- instars 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, Limacodid 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
''Parasa indetermina'', the stinging rose moth, is a moth of the family Limacodidae. It is found in the United States from New York to Florida, west to Missouri, Texas, and Oklahoma.
The wingspan is 23–30 mm. Adults are on wing from June ...
'')
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 state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah borders the Malaysian state of Sarawak to the southwest and the North Kalimantan province of Indonesia to the south. The Federal Territory ...
, 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
''Latoia'' is a genus of moths in the family Limacodidae. It was described by Félix Édouard Guérin-Méneville in 1844.
Species
Some species of this genus are:
*''Latoia albicosta'' (Hampson, 1910)
*''Latoia albifrons'' Guérin-Méneville, 184 ...
'', ''Parasa lepida
''Parasa lepida'', the nettle caterpillar or blue-striped nettle grub, is a moth of the family Limacodidae that was described by Pieter Cramer in 1799. It is a native minor pest found in the Indo-Malayan region, including India, Sri Lanka, Vietn ...
'', '' Penthocrates meyrick'', '' Aarodia nana'') have caused serious defoliation of palms.
Notable species
* Hag moth or monkey slug (''Phobetron pithecium
''Phobetron pithecium'', the hag moth, is a moth of the family Limacodidae. Its larva is known as the monkey slug.
Lifecycle
One generation a year occurs in the north, but two or more happen in the southern United States.
Larva
The larva is ...
'')
* 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
''Latoia'' is a genus of moths in the family Limacodidae. It was described by Félix Édouard Guérin-Méneville in 1844.
Species
Some species of this genus are:
*''Latoia albicosta'' (Hampson, 1910)
*''Latoia albifrons'' Guérin-Méneville, 184 ...
'')
* Saddleback caterpillar (''Acharia stimulea
The saddleback caterpillar (''Acharia stimulea'', formerly ''Sibine stimulea'') is the larva of a species of moth native to eastern North America. It is also found in Mexico. The species belongs to the family of slug caterpillars, Limacodidae.
T ...
'')
References
External links
Brisbane Limacodids, with photo of cocoon.
Moths of Borneo
{{Authority control
Limacodidae,
Moth families