View source for Bagworm moth

{{Short description|Family of moths known as Psychidae}}
{{Redirect|Bagworm|text=This may also refer to two [[Macrolepidoptera]] species, the [[fall webworm]] (''Hyphantria cunea'') or the [[eastern tent caterpillar]] (''Malacosoma americanum'')}}
{{More citations needed|date=February 2018}}
{{Automatic taxobox
| name = Bagworm moths
| image = Iphierga.jpg
| image_caption = Adult of an undescribed ''[[Iphierga]]'' [[species]] from [[Aranda, Australian Capital Territory|Aranda]] (Australia)
| image2 = Case moth02.jpg
| image2_caption = "Bag" of unidentified species
| taxon = Psychidae
| authority = [[Jean Baptiste Boisduval|Boisduval]], 1828
| diversity_ref =<ref name="Nieukerken et al 2011"/>
| diversity_link = #Systematics
| diversity = 10 subfamilies, 241 genera and 1,350 species
}}
[[File:Meture-Elongatus.jpg|thumb|Bag of ''[[Metura elongatus]]'' which can grow to more than {{cvt|120|mm}} in length]]
[[File:Bagworm moth caterpillar locomotion.webm|thumb|Bagworm moth caterpillar locomotion]]

The '''Psychidae''' ('''bagworm moths''', also simply '''bagworms''' or '''bagmoths''') are a [[Family (biology)|family]] of the [[Lepidoptera]] ([[butterflies]] and [[moth]]s). The bagworm family is fairly small, with about 1,350 [[species]]<ref>{{cite book |last1=Sobczyk |first1=Thomas |title=World Catalogue of Insects: Psychidae (Lepidoptera) |date=2011 |publisher=UWA Publishing |isbn=978-87-88757-98-9 }}{{page needed|date=June 2020}}</ref> described. Bagworm species are found globally, with some, such as the [[snailcase bagworm]] (''Apterona helicoidella''), in modern times settling continents where they are not native.

Another common name for the Psychidae is "'''case moths'''", but this is just as well used for the [[case-bearer]]s (Coleophoridae). The names refer to the habits of [[caterpillars]] of these two families, which build small protective cases in which they can hide. The bagworms belong to the [[Taxonomic rank|superfamily]] [[Tineoidea]], which is a [[basal (evolution)|basal]] lineage of the [[Ditrysia]] (as is [[Gelechioidea]], which includes case-bearers). This means that the bagworms and case-bearers are only as closely related to each other as either is to [[butterflies]] (Rhopalocera).

Most bagworms are inoffensive to humans and inconspicuous; some are occasional nuisance [[pest (organism)|pest]]s. However, a few species can become more serious pests, and have caused significant damage e.g. to [[acacia|wattle]] (''Acacia mearnsii'') in [[South Africa]] and [[orange (fruit)|orange]] (''Citrus × sinensis'') in [[Florida]]. If detected early, picking the cases from the trees while in their pupa stage is an effective way to check an infestation; otherwise, [[insecticide]]s are used. One bagworm species, the [[fangalabola]] (''Deborrea malgassa'') of [[Madagascar]], is in some places encouraged to breed on wattle trees, because its pupae are collected as a [[protein]]-rich food.

==Description==
The [[caterpillar]] [[larva]]e of Psychidae construct cases out of silk and environmental materials such as [[sand]], [[soil]], [[lichen]], or [[plant]] materials. These cases are attached to rocks, trees or fences while resting or during their [[pupa]] stage, but are otherwise mobile. The larvae of some species eat [[lichen]], while others prefer green leaves. In many [[species]], the adult females lack wings and are therefore difficult to identify accurately. Case-bearer cases are usually much smaller, flimsier, and consist mainly of silk, while bagworm "bags" resemble [[caddisfly]] cases in their outward appearance &ndash; a mass of (mainly) plant [[detritus]] spun together with silk on the inside.

Bagworm cases range in size from less than 1&nbsp;cm to 15&nbsp;cm among some [[tropical]] species. Each species makes a case particular to its species, making the case more useful to identify the species than the creature itself. Cases among the more primitive species are flat. More specialized species exhibit a greater variety of case size, shape, and composition, usually narrowing on both ends. The attachment substance used to affix the bag to a host plant or structure has a higher tensile strength than that of other moth species, requiring greater force to initiate breakage.<ref>{{Cite journal |last1=Kono |first1=Nobuaki |last2=Nakamura |first2=Hiroyuki |last3=Tateishi |first3=Ayaka |last4=Numata |first4=Keiji |last5=Arakawa |first5=Kazuharu |date=2021-07-26 |title=The balance of crystalline and amorphous regions in the fibroin structure underpins the tensile strength of bagworm silk |journal=Zoological Letters |volume=7 |issue=1 |pages=11 |doi=10.1186/s40851-021-00179-7 |doi-access=free |issn=2056-306X |pmc=8314566 |pmid=34311769}}</ref> Body markings are rare. Adult females of many bagworm species are [[larviform female|larviform]], with only [[vestigial]] wings, legs, and mouthparts. In some species, [[parthenogenesis]] is known. The adult males of most species are strong fliers with well-developed wings and feathery antennae but survive only long enough to reproduce due to underdeveloped mouthparts that prevent them from feeding. Most male bagworm wings have few of the scales characteristic of most moths, instead having a thin covering of hairs.

<gallery widths="200px" heights="200px">

File:Pachythelia villosella.case.jpg|"Bag" of ''[[Pachythelia villosella]]'' ([[Oiketicinae]])
File:Grasninella m.JPG|Adult specimen of ''[[Phalacropterix graslinella]]'' (Oiketicinae)
File:Bagworm Moth larva Negev.JPG|Bagworm larva in the [[Negev]] (April 2014). Case is made mostly of feathery stork's bill seeds (''[[Erodium cicutarium]]'').
File:Family Psychidae444.jpg|Bagworm (possibly ''[[Hyalarcta huebneri]]'') extending its forequarters from its case in the act of [[Terrestrial locomotion|locomotion]].
</gallery>

==Ecology==
In the larval stage, bagworms extend their head and [[Thorax (insect anatomy)|thorax]] from their mobile case to devour the leaves of host plants, often leading to the death of their [[host (biology)|host]]s. [[Tree]]s infested with bagworms exhibit increasingly damaged foliage as the infestation increases until the leaves are stripped bare.<ref>{{Cite web |last=Matthew |first=George |last2=Nair |first2=K.S.S. |date=12 January 1991 |title=THE BAGWORM, PTEROMA PLAGIOPHLEPS HAMPS. IN FOREST PLANTATIONS OF PARASERIANTHES FALCATARIA |url=https://www.researchgate.net/publication/364330517_THE_BAGWORM_PTEROMA_PLAGIOPHLEPS_HAMPS_IN_FOREST_PLANTATIONS_OF_PARASERIANTHES_FALCATARIA |url-status=live |access-date=20 November 2025 |website=ResearchGate}}</ref> Some bagworms are specialized in their host plants ([[monophagous]]), while others can feed on a variety of plant species (polyphagous). A few species also consume small [[arthropod]]s (such as the [[camphor scale]] ''[[Pseudaonidia duplex]]'', a [[scale insect]]).<ref>{{Cite journal |last=Davis |first=Donald Ray |last2=Quintero |first2=Diomedes A. |last3=Cambra |first3=Roberto A. T. |last4=Aiello |first4=Annette |date=2008-07-01 |title=Biology of a New Panamanian Bagworm Moth (Lepidoptera: Psychidae) with Predatory Larvae, and Eggs Individually Wrapped in Setal Cases |url=http://openurl.ingenta.com/content/xref?genre=article&issn=0013-8746&volume=101&issue=4&spage=689 |journal=Annals of the Entomological Society of America |language=en |volume=101 |issue=4 |pages=689–702 |doi=10.1603/0013-8746(2008)101[689:BOANPB]2.0.CO;2}}</ref><ref>{{Cite journal |last=Villanueva |first=Raul T. |last2=Rodrigues |first2=Jose C. V. |last3=Childers |first3=Carl C. |date=2005-05-01 |title=Larval Cryptothelea gloverii (Lepidoptera: Psycidae), an arthropod predator and herbivore on Florida citrus |url=https://doi.org/10.1007/s10493-005-1673-0 |journal=Experimental & Applied Acarology |language=en |volume=36 |issue=1 |pages=83–92 |doi=10.1007/s10493-005-1673-0 |issn=1572-9702}}</ref> One bagworm species was found to eat an orb-web of ''Plebs sachalinensis'' (Araneae, Araneidae) entirely.<ref>{{cite journal |last1=Koshidaka |first1=Naoki |last2=Takasuka |first2=Keizo |title=Discovery of a bagworm devouring an orb web |journal=Arachnology |date=5 August 2019 |volume=18 |issue=2 |pages=147 |doi=10.13156/arac.2018.18.2.147 |s2cid=201572602 }}</ref>

Since bagworm cases are composed of silk and the materials from their habitat, they are naturally camouflaged from predators. [[Predator]]s include [[bird]]s and other [[insect]]s. Birds often eat the egg-laden bodies of female bagworms after they have died. Since the eggs are very hard-shelled, they can pass through the bird's [[digestive system]] unharmed, promoting the spread of the species over wide areas.<ref>{{cite journal |last1=Barbosa |first1=Pedro |last2=Krischik |first2=Vera |last3=Lance |first3=David |title=Life-history Traits of Forest-inhabiting Flightless Lepidoptera |journal=The American Midland Naturalist |date=October 1989 |volume=122 |issue=2 |pages=262–274 |doi=10.2307/2425912 |jstor=2425912 |url=https://www.jstor.org/stable/2425912 |access-date=26 October 2022|url-access=subscription }}</ref>

A bagworm begins to build its case as soon as it hatches. Once the case is built, only adult males ever leave the case, never to return, when they take flight to find a mate. Bagworms add material to the front of the case as they grow, excreting waste materials through the opening in the back of the case.  When satiated with leaves, a bagworm [[caterpillar]] secures its case and pupates.<ref>{{Cite journal |last=Rhainds |first=Marc |last2=Davis |first2=Donald R. |last3=Price |first3=Peter W. |date=2009-01-01 |title=Bionomics of Bagworms (Lepidoptera: Psychidae) |url=https://www.annualreviews.org/doi/10.1146/annurev.ento.54.110807.090448 |journal=Annual Review of Entomology |language=en |volume=54 |issue=1 |pages=209–226 |doi=10.1146/annurev.ento.54.110807.090448 |issn=0066-4170}}</ref> The adult female, which is wingless, either emerges from the case long enough for breeding or remains in the case while the male extends his [[abdomen]] into the female's case to breed.<ref>{{cite book |last1=Resh |first1=Vincent H. |last2=Cardé |first2=Ring T. |title=Encyclopedia of Insects |date=2009 |publisher=Academic Press |isbn=978-0-08-092090-0 |url=https://www.sciencedirect.com/book/9780123741448/encyclopedia-of-insects |access-date=2020-06-06 |archive-date=2020-06-14 |archive-url=https://web.archive.org/web/20200614124512/https://www.sciencedirect.com/book/9780123741448/encyclopedia-of-insects |url-status=live }}{{page needed|date=June 2020}}</ref> Females lay their eggs in their case and die. The female [[evergreen bagworm]] (''Thyridopteryx ephemeraeformis'') dies without laying eggs, and the larval bagworm offspring emerge from the parent's body. Some bagworm species are [[parthenogenetic]], meaning their eggs develop without male fertilization. Each bagworm generation lives just long enough as adults to mate and reproduce in their annual cycle.<ref>{{cite journal |last1=Davis |first1=Donald Ray |last2=Quintero A. |first2=Diomedes |last3=Cambra T. |first3=Roberto A. |title=Biology of a New Panamanian Bagworm Moth (Lepidoptera: Psychidae) with Predatory Larvae, and Eggs Individually Wrapped in Setal Cases. |journal=Annals of the Entomological Society of America |date=July 2008 |volume=101 |issue=4 |pages=689–702 |doi=10.1093/aesa/101.4.689 |url=http://rave.ohiolink.edu/ejournals/article/312874782 |access-date=26 October 2022|url-access=subscription }}</ref>

== Systematics ==
Ten [[subfamilies]]<ref name="Nieukerken et al 2011">{{cite journal |last1=Nieukerken |first1=Erik J. Van |last2=Kaila |first2=Lauri |last3=Kitching |first3=Ian J. |last4=Kristensen |first4=Niels P. |last5=Lees |first5=David C. |last6=Minet |first6=Joël |last7=Mitter |first7=Charles |last8=Mutanen |first8=Marko |last9=Regier |first9=Jerome C. |last10=Simonsen |first10=Thomas J. |last11=Wahlberg |first11=Niklas |last12=Yen |first12=Shen-Horn |last13=Zahiri |first13=Reza |last14=Adamski |first14=David |last15=Baixeras |first15=Joaquin |last16=Bartsch |first16=Daniel |last17=Bengtsson |first17=Bengt Å. |last18=Brown |first18=John W. |last19=Bucheli |first19=Sibyl Rae |last20=Davis |first20=Donald R. |last21=Prins |first21=Jurate De |last22=Prins |first22=Willy De |last23=Epstein |first23=Marc E. |last24=Gentili-Poole |first24=Patricia |last25=Gielis |first25=Cees |last26=Hättenschwiler |first26=Peter |last27=Hausmann |first27=Axel |last28=Holloway |first28=Jeremy D. |last29=Kallies |first29=Axel |last30=Karsholt |first30=Ole |last31=Kawahara |first31=Akito Y. |last32=Koster |first32=Sjaak J. C. |last33=Kozlov |first33=Mikhail V. |last34=Lafontaine |first34=J. Donald |last35=Lamas |first35=Gerardo |last36=Landry |first36=Jean-François |last37=Lee |first37=Sangmi |last38=Nuss |first38=Matthias |last39=Park |first39=Kyu-Tek |last40=Penz |first40=Carla |last41=Rota |first41=Jadranka |last42=Schintlmeister |first42=Alexander |last43=Schmidt |first43=B. Christian |last44=Sohn |first44=Jae-Cheon |last45=Solis |first45=M. Alma |last46=Tarmann |first46=Gerhard M. |last47=Warren |first47=Andrew D. |last48=Weller |first48=Susan |last49=Yakovlev |first49=Roman V. |last50=Zolotuhin |first50=Vadim V. |last51=Zwick |first51=Andreas |title=Order Lepidoptera Linnaeus, 1758. In : Zhang, Z.-Q. (Ed.) Animal biodiversity: An outline of higher-level classification and survey of taxonomic richness |journal=Zootaxa |date=23 December 2011 |volume=3148 |issue=1 |pages=212–221 |doi=10.11646/zootaxa.3148.1.41 }}</ref> and about 240 genera are recognized among the bagworms.

The subfamilies of Psychidae, with some notable genera and species also listed, are:

<!-- 
Important genera without articles can be collected here, until the subfamilies get their own articles. Species can also be put here, but when they have no articles they should be outcommented as below. Only species with articles should be visible, and when genus articles exist species should be put there.
-->
<div float="left">
{{col-begin|width=75%}}
{{col-1-of-3}}
'''Subfamily Epichnopteriginae''' 
* ''[[Acentra]]''
* ''[[Bijugis]]''
* ''[[Epichnopterix]]''
** ''[[Epichnopterix plumella]]''
* ''[[Heliopsychidea]]''
* ''[[Mauropterix]]''
* ''[[Montanima]]''
* ''[[Psychidea]]''
* ''[[Psychocentra]]''
* ''[[Rebelia]]''
* ''[[Reisseronia]]''
* ''[[Stichobasis]]''
** ''[[Stichobasis postmeridianus]]''
* ''[[Whittleia]]''
** ''[[Whittleia retiella]]''
'''Subfamily Naryciinae'''
* ''[[Dahlica]]'' <small>Enderlein, 1912</small>
** ''[[Dahlica triquetrella]]''
* ''[[Eosolenobia]]'' <small>Filipjev, 1924</small>
* ''[[Narycia]]''
* ''[[Postsolenobia]]'' <small>Meier, 1958</small>
* ''[[Siederia]]''
'''Subfamily Oiketicinae'''
* ''[[Apterona]]''
** ''[[Apterona helicoidella]]'' &ndash; (snailcase bagworm)
* ''[[Canephora (moth)|Canephora]]''
** ''[[Canephora hirsuta]]''
* ''[[Cryptothelea]]'' (= ''Platoeceticus'')
** ''[[Cryptothelea gloverii]]''
* ''[[Astala (moth)|Astala]]''
* ''[[Kotochalia]]''
** ''[[Kotochalia junodi]]'' &ndash; (wattle bagworm)
* ''[[Hyalarcta]]''
<!--
** ''[[Hyalarcta huebneri]]''
* ''[[Eurukuttarus]]''
** ''[[Eurukuttarus confederata]]'' &ndash; (grass bagworm)
* ''[[Metura]]''
** ''[[Metura elongatus]]''
-->
* ''[[Deborrea]]''
** ''[[Deborrea malgassa]]'' &ndash; (fangalabola)
* ''[[Eumeta]]''
** ''[[Eumeta crameri]]'' &ndash; (faggot worm)
* ''[[Megalophanes]]''
** ''[[Megalophanes viciella]]''
* ''[[Oiketicus]]''
* ''[[Zamopsyche]]''
* ''[[Eucoloneura]]''
* ''[[Pachythelia]]''
<!--
** ''[[Pachythelia villosella]]''
-->
* ''[[Phalacropterix]]''
<!--
** ''[[Phalacropterix graslinella]]''
-->
* ''[[Ptilocephala]]''
** ''[[Ptilocephala plumifera]]''
* ''[[Sterrhopterix]]''
** ''[[Sterrhopterix fusca]]''
* ''[[Thyridopteryx]]''
{{col-2-of-3}}
'''Subfamily Placodominae'''
* ''[[Placodoma]]''
'''Subfamily [[Psychinae]]'''
* ''[[Liothula]]''
** ''[[Liothula omnivora]]''
* ''[[Luffia]]''
** ''[[Luffia ferchaultella]]''
** ''[[Luffia lapidella]]''
* ''[[Psyche (moth)|Psyche]]''<!-- type species was given as "''Psyche carpini'' (= ''Psyche casta'')" -->
** ''[[Psyche casta]]''
** ''[[Psyche crassiorella]]''
** ''[[Psyche rassei]]''
** ''[[Psyche saxicolella]]''
* ''[[Prochalia]]''
'''Subfamily Taleporiinae'''
* ''[[Bankesia]]'' <small>Tutt, 1899</small>
** ''[[Bankesia conspurcatella]]''
* ''[[Brevantennia]]'' <small>Sieder, 1953</small>
* ''[[Cebysa]]''
** ''[[Cebysa leucotelus]]'' &ndash; (Australian bagmoth)
* ''[[Diplodoma]]''
** ''[[Diplodoma adspersella]]''
* ''[[Eotaleporia]]'' <small>Sauter, 1986</small>
* ''[[Praesolenobia]]'' <small>Sieder, 1954</small>
* ''[[Pseudobankesia]]'' <small>Meier, 1963</small>
* ''[[Sciopetris]]'' <small>Meyrick, 1891</small>
* ''[[Taleporia]]''
'''Subfamily Typhoniinae'''
* ''[[Typhonia]]''
** ''[[Typhonia animosa]]''
** ''[[Typhonia bimaculata]]''
{{col-3-of-3}}
'''''[[Incertae sedis]]'''''
* ''[[Eumasia]]'' 
** ''[[Eumasia crisostomella]]''
** ''[[Eumasia parietariella]]'' <small>(Heydenreich, 1851)</small>
* ''[[Iphierga]]''
** ''[[Iphierga chrysophaes]]'' <small> Turner, 1917 </small>
'''Subfamily Scoriodytinae'''
*''[[Scoriodyta]]'' <small>Meyrick, 1888</small>
** ''[[Scoriodyta conisalia]]'' <small>Meyrick, 1888</small>
'''Subfamily Metisinae'''
*''[[Metisa]]'' <small>Hampson, 1895</small>
** ''[[Metisa canifrons]]'' <small>Hampson, 1895</small>
'''Subfamily Pseudarbelinae'''
*''[[Pseudarbela]]'' <small>Sauber, 1902</small>
** ''[[Pseudarbela celaena]]'' <small>(Bethune-Baker, 1904)</small>
** ''[[Pseudarbela aurea]]'' <small>(Bethune-Baker, 1904)</small>
** ''[[Pseudarbela papuana]]'' <small>Clench, 1959</small>
** ''[[Pseudarbela semperi]]'' <small>Sauber, 1902</small>
*''[[Casana]]'' <small>Walker, 1865</small>
** ''[[Casana trochiloides]]'' <small>Walker, 1865</small>
*''[[Linggana]]'' <small>Roepke, 1957</small>
** ''[[Linggana cardinaali]]'' <small>Roepke, 1957</small>
{{col-end}}
</div>

==Applications==
The silk of bagworm moth larvae is reportedly "more durable than [[spider silk]]".<ref name="asahi-2024">{{Cite news |last=Yamamoto |first=Seisaku |date=2024-11-21 |title=Bagworm moth silk developed into eco-friendly, strong textile |url=https://www.asahi.com/ajw/articles/15518047 |access-date=2025-05-14 |work=The Asahi Shimbun}}</ref> Japanese pharmaceutical company [[Kowa (company)|Kowa]] and the [[National Agriculture and Food Research Organization]] announced a new textile, Minolon, in 2024, that combined [[carbon fibers]] with sheets of bagworm silk. The resulting material was claimed to be environmentally friendly, with Kowa planning to sell it to aircraft, automobile, and sporting good manufacturers.<ref name="asahi-2024" />

==References==
{{Reflist}}

==External links==
{{Commons category|Psychidae}}
{{Wikispecies|Psychidae}}
* [http://web.extension.illinois.edu/cfiv/homeowners/010818.html Bagworm, Fall Webworm or Eastern Tent Caterpillar?] {{Webarchive|url=https://web.archive.org/web/20140820045403/http://web.extension.illinois.edu/cfiv/homeowners/010818.html |date=2014-08-20 }}, August 18, 2001.  Sandra Mason, University of Illinois Extension.  Accessed May 31, 2010.
* [http://lancaster.unl.edu/hort/bagworms.shtml Bagworm Control, Photos and Video from University of Nebraska-Lincoln Extension] {{Webarchive|url=https://web.archive.org/web/20191202071240/http://lancaster.unl.edu/hort/bagworms.shtml |date=2019-12-02 }}
* [http://extension.psu.edu/bagworms Bagworm fact sheet from Penn State]
* [https://web.archive.org/web/20020816150456/http://nearctica.com/nomina/lepid/lepn-p.htm Psychids] Accessed 2002-06-26
* [http://www.ibiblio.org/e-notes/VRML/blaxxun/caterpillar.htm Bagworm Silk cases]

{{Lepidoptera}}
{{Palm oil}}
{{Taxonbar|from=Q844816}}
{{Authority control}}

[[Category:Psychidae]]
[[Category:Moth families]]