The bean weevils or seed beetles are a
subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...
(Bruchinae) of
weevils, which in turn are a subset of
beetle
Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...
s. The Bruchinae now placed in the family
Chrysomelidae
The beetle family Chrysomelidae, commonly known as leaf beetles, includes over 37,000 (and probably at least 50,000) species in more than 2,500 genera, making it one of the largest and most commonly encountered of all beetle families. Numerous s ...
, though they have historically been treated as a separate family. The subfamily includes about 1,650 species and are found worldwide.
Bean weevils are generally compact and oval in shape, with small heads somewhat bent under. Sizes range from for some tropical species. Colors are usually black or brown, often with mottled patterns. Although their
mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbone i ...
s may be elongated, they do not have the long snouts characteristic of other weevils. A defining characteristic of this subfamily is that the
elytra don't quite reach the tip of 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 (as seen in the header image).
The Bruchinae are
granivores, and typically infest various kinds of
seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...
s or
bean
A bean is the seed of some plants in the legume family (Fabaceae) used as a vegetable for human consumption or animal feed. The seeds are often preserved through drying (a ''pulse''), but fresh beans are also sold. Dried beans are traditi ...
s (hence their
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...
s), living most of their lives inside a single seed; Host plants tend to be
legume
Legumes are plants in the pea family Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consum ...
s, but species will also be found in
Convolvulaceae
Convolvulaceae (), commonly called the bindweed, bindweeds or morning glory, morning glories, is a Family (biology), family of about 60 genera and more than 1,650 species. These species are primarily herbaceous vines, but also include trees, sh ...
,
Arecaceae
The Arecaceae () is a family (biology), family of perennial plant, perennial, flowering plants in the Monocotyledon, monocot order Arecales. Their growth form can be climbing palm, climbers, shrubs, tree-like and stemless plants, all commonly k ...
, and
Malvaceae
Malvaceae (), or the mallows, is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include Theobroma cacao, cacao, Cola (plant), cola, cotton, okra, Hibiscus sabdariffa, ...
. The adults deposit eggs on seeds of these plants, then the larvae chew their way into the seed. When ready to
pupa
A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages th ...
te, the larvae typically cut an exit hole, then return to their feeding chamber. Due to this, several species are considered
pests. The adult weevils have a habit of feigning death and dropping from a plant when disturbed.
Several species are native to Great Britain, but there are also records of several
introduced species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...
from stored products in
warehouse
A warehouse is a building for storing goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial parks on the rural–urban fringe, out ...
s and
dwelling
In law, a dwelling (also known as a residence, abode or domicile) is a self-contained unit of accommodation – such as a house, apartment, mobile home, houseboat, recreational vehicle, or other "substantial" structure – used as a home by ...
s, although these species cannot proliferate outside of
heated buildings in that climate.
Genera
This list of genera uses the new
classification
Classification is the activity of assigning objects to some pre-existing classes or categories. This is distinct from the task of establishing the classes themselves (for example through cluster analysis). Examples include diagnostic tests, identif ...
scheme, treating the bean weevils as a subfamily with six extant tribes, eight or nine subtribes, and one extinct tribe. The former names and ranks for the tribes and subtribes under the old classification, treating the been weevils as a family, are given in parentheses (except for Myanmaropini, which was established only for the new classification).
* Tribe
Amblycerini Bridwell, 1932 (= Subfamily Amblycerinae)
** Subtribe
Amblycerina Bridwell, 1932 (= Tribe Amblycerini)
*** ''
Amblycerus'' Thunberg, 1815
** Subtribe
Spermophagina Borowiec, 1987 (= Tribe Spermophagini)
*** ''
Spermophagus'' Schoenherr, 1833
*** ''
Zabrotes'' Horn, 1885
* Tribe
Bruchini Latreille, 1802 (= Subfamily Bruchinae)
** Subtribe
Acanthoscelidina Bridwell, 1946 (= Tribe Acanthoscelidini)
*** ''
Abutiloneus'' Bridwell, 1946
*** ''
Acanthoscelides'' Schilsky, 1905
*** ''
Algarobius'' Bridwell, 1946
*** ''
Althaeus'' Bridwell, 1946
*** ''
Bonaerius'' Bridwell, 1952
*** ''
Caryedes'' Hummel, 1827
*** ''
Cosmobruchus'' Bridwell, 1931
*** ''
Ctenocolum'' Kingsolver & Whitehead, 1974
*** ''
Dahlibruchus'' Bridwell, 1931
*** ''
Gibbobruchus'' Pic, 1913
*** ''
Lithraeus'' Bridwell, 1952
*** ''
Margaritabruchus'' Romero & Johnson, 2001
*** ''
Meibomeus'' Bridwell, 1946
*** ''
Megasennius'' Whitehead & Kingsolver, 1975
*** ''
Merobruchus'' Bridwell, 1946
*** ''
Mimosestes'' Bridwell, 1946
*** ''
Neltumius'' Bridwell, 1946
*** ''
Neobruchidius'' Johnson & Romero, 2006
*** ''
Palpibruchus'' Borowiec, 1987
*** ''
Pectinibruchus'' Kingsolver, 1967
*** ''
Penthobruchus'' Kingsolver, 1973
*** ''
Pseudopachymerina'' Zacher, 1952
*** ''
Pygiopachymerus'' Pic, 1911
*** ''
Rhipibruchus'' Bridwell, 1932
*** ''
Scutobruchus'' Kingsolver, 1968
*** ''
Sennius'' Bridwell, 1946
*** ''
Spatulobruchus'' Borowiec, 1987
*** ''
Stator
The stator is the stationary part of a rotary system, found in electric generators, electric motors, sirens, mud motors, or biological rotors (such as bacterial flagella or ATP synthase). Energy flows through a stator to or from the rotat ...
'' Bridwell, 1946
*** ''
Stylantheus'' Bridwell, 1946
** Subtribe
Bruchidiina Bridwell, 1946 (= Tribe Bruchidiini)
*** ''
Acanthobruchidius'' Borowiec, 1980
*** ''
Borowiecius'' Anton, 1994
*** ''
Bruchidius'' Schilsky, 1905
*** ''
Callosobruchus'' Pic, 1902
*** ''
Conicobruchus'' Decelle, 1951
*** ''
Decellebruchus'' Borowiec, 1987
*** ''
Horridobruchus'' Borowiec, 1984
*** ''
Kingsolverius'' Borowiec, 1987
*** ''
Megabruchidius'' Borowiec, 1984
*** ''
Palaeoacanthoscelides'' Borowiec, 1985
*** ''
Parasulcobruchus'' Anton, 1999
*** ''
Pygobruchidius'' Pic, 1951
*** ''
Salviabruchus'' Decelle, 1982
*** ''
Specularius'' Bridwell, 1938
*** ''
Sulcobruchus'' Chûjô, 1937
*** ''
Tuberculobruchus'' Decelle, 1951
** Subtribe
Bruchina Latreille, 1802 (= Tribe Bruchini)
*** ''
Bruchus'' Linnaeus, 1767
** Subtribe
Megacerina Bridwell, 1946 (= Tribe Megacerini)
*** ''
Megacerus'' Fåhraeus, 1839
* Tribe
Eubaptini Bridwell, 1932 (= Subfamily Eubaptinae)
** ''
Eubaptus'' Lacordaire, 1845
* Tribe
Kytorhinini Bridwell, 1832 (= Subfamily Kytorhininae)
** ''
Kytorhinus'' Fischer von Waldheim, 1809
* Tribe
Pachymerini Bridwell, 1929 (= Subfamily Pachymerinae)
** Subtribe
Caryedontina Bridwell, 1929 (= Tribe Caryedontini)
*** ''
Aforedon'' Decelle, 1965
*** ''
Caryedon'' Schoenherr, 1823
*** ''
Caryotrypes'' Decelle, 1968
*** ''
Exoctenophorus'' Decelle, 1968
*** ''
Mimocaryedon'' Decelle, 1968
** Subtribe
Caryopemina Bridwell, 1929 (= Tribe Caryomepini)
*** ''
Caryopemon'' Jekel, 1855
*** ''
Diegobruchus'' Pic, 1913
*** ''
Protocaryopemon'' Borowiec, 1987
** Subtribe
Pachymerina Bridwell, 1929 (= Tribe Pachymerini)
*** ''
Butiobruchus'' Prevett, 1966
*** ''
Caryobruchus'' Bridwell, 1929
*** ''
Caryoborus'' Schoenherr, 1833
*** ''
Pachymerus'' Thunberg, 1805
***†''
Mesopachymerus'' Poinar, 2005
Canadian amber,
Campanian
The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...
* Tribe
Rhaebini Chapuis, 1874 (= Subfamily Rhaebinae)
** ''
Rhaebus'' Fischer von Waldheim, 1824
* Tribe †
Myanmaropini Legalov ''et al.'', 2020
**†''
Myanmarops'' Legalov ''et al.'', 2020
Burmese amber
Burmese amber, also known as Burmite or Kachin amber, is amber from the Hukawng Valley in northern Myanmar. The amber is dated to around 100 million years ago, during the latest Albian to earliest Cenomanian ages of the mid-Cretaceous period. Th ...
, Myanmar,
Cenomanian
The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...
Notes
References
*
John M. Kingsolver, "Bruchidae", in
Ross H. Arnett, Jr. and
Michael C. Thomas, ''
American Beetles
''American Beetles'' is a comprehensive description of the beetles of North America north of the tropical area of Mexico. It was started by Ross H. Arnett, Jr. as an update of his classic ''The Beetles of the United States''; along with Michael ...
'' (CRC Press, 2002), vol. 2 (note that this reference itself indicates the group is a subfamily, and the change was made only after the chapter was written)
External links
BRUCHBASE
{{Taxonbar, from1=Q217617, from2=Q13167641
Storage pests