''Apterona helicoidella'' (snailcase bagworm) is a
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 ...
of the
Psychidae
The Psychidae (bagworm moths, also simply bagworms or bagmoths) are a family of the Lepidoptera (butterflies and moths). The bagworm family is fairly small, with about 1,350 species described. Bagworm species are found globally, with some, s ...
family. It is widely distributed in
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...
, from
Portugal
Portugal, officially the Portuguese Republic, In recognized minority languages of Portugal:
:* mwl, República Pertuesa is a country located on the Iberian Peninsula, in Southwestern Europe, and whose territory also includes the Macaronesian ...
through most of central Europe and the
Alps
The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, ...
, up to the
Ural. It is also found on the
Balkan
The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...
and in
Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
. It was introduced in the United States by accident during the 1940s. It is now found in many mid-Atlantic states, including
Pennsylvania
Pennsylvania (; (Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Ma ...
, and has also been reported in the Pacific coastal states, as well as
Colorado
Colorado (, other variants) is a state in the Mountain states, Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the wes ...
,
Michigan
Michigan () is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the List of U.S. states and ...
,
Nevada
Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...
,
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...
and
Idaho
Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and W ...
. It has been collected in
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...
as well (
Royal Ontario Museum Collection).
In southern Europe a subspecies with two sexes exists with small males that have light grey wings. This subspecies is called ''Apterona helicoidella crenulella.''
North of the Alps the species is
parthenogenetic
Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and developmen ...
and is called ''Apterona helicoidella helicoidella''. Only females are present in this subspecies. They form a case that looks like a small
snail
A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class G ...
. The females grow within the case, becoming adults in the late summer. Unlike most
bagworms, the case is constructed of soil particles and feces instead of leaves and twigs. The snailcase bagworm begins constructing its case at birth and remains inside for the rest of its life. This subspecies is unusual in that it is parthenogenetic; all individuals are females, and they reproduce without mating. Each female produces one to two dozen eggs, which are deposited within the case.
The case of a snailcase bagworm, not surprisingly, resembles a small snail about 4 mm in diameter with coloration similar to the soil. The larvae are greenish or reddish gray with a black head that protrudes from the case to feed.
Though the snailcase bagworm doesn't cause the damage of related species such as the
evergreen bagworm, they are a nuisance to humans by attaching to the sides of homes and buildings. Once the larvae are full-grown and moving to pupate, they cannot be controlled with insecticides. The best way to keep them off the sides of buildings is by using temporary barriers like sticky tape or flanges. They can be knocked off buildings with a strong spray of water before they attach. After they are attached, removal is difficult.
They consume small areas of a leaf surface, rarely causing significant damage, though it has been found to feed on most vegetables, ornamentals, legumes, fruit and other trees, and many species of annual herbs. Reported food plants include ''
Potentilla neumanniana'', ''
Erodium cicutarium
''Erodium cicutarium'', also known as common stork's-bill, redstem filaree, redstem stork's bill or pinweed, is a herbaceous annual – or in warm climates, biennial – member of the family Geraniaceae of flowering plants. It is native to Macaro ...
'', ''
Teucrium
''Teucrium'' is a cosmopolitan genus of flowering plants in the family Lamiaceae, commonly known as germanders. Plants in this genus are perennial herbs or shrubs, with branches that are more or less square in cross-section, leaves arranged in op ...
'', ''
Artemisia vulgaris
''Artemisia vulgaris'', the common mugwort, is a species of flowering plant in the daisy family Asteraceae. It is one of several species in the genus '' Artemisia'' commonly known as mugwort, although ''Artemisia vulgaris'' is the species most ...
'', ''
Helianthemum nummularium
''Helianthemum nummularium'' (known as common rock-rose) is a species of rock-rose (Cistaceae), native to most of Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical s ...
'' and ''
Alyssum montanum
''Alyssum montanum'' is a species of flowering plant belonging to the family Brassicaceae. It is an evergreen, prostrate perennial with small, hairy, greyish leaves. It typically grows to 10-15 centimeters tall and 30-45 centimeters across. It ...
''.
Sources
Penn State notes
References
External links
BioLibLepiforum.de{{Taxonbar, from=Q1765873
Psychidae
Moths of Europe
Moths of Asia
Moths of North America
Moths described in 1827
Taxa named by Jean Nicolas Vallot