Belidae
Encyclopedia
Belidae is a family
of weevils, called belids or primitive weevils because they have straight antennae, unlike the "true weevils" or Curculionidae
which have elbowed antennae. They are sometimes known as "cycad
weevils", but this properly refers to a few species from the genera
Parallocorynus and Rhopalotria.
n distribution, occurring only in the Australia
–New Guinea
–New Zealand
region up to Southeast Asia
, South
and Central America
(barely reaching North America
), some Pacific islands (notably the Hawaiian Islands
) and a few places in Africa
. Many lineages of belids are notable for their highly relict
ual distribution; for example the Aglycyderini
are found in two areas on opposite sides of the Earth, with no such beetles known from anywhere in between.
Belids were more widespread during the Late Jurassic
to Early Cretaceous
, about , when they were found at least in Central Asia
, Spain
and Brazil
. Paleogene
species belonging to still-living tribe
s are known from Europe
and North America
.
are typically elongated and cylindrical. Some belines resemble other weevils, like the genus Lixus
of the true weevil family (Curculionidae
), or brentids
. Others are mimetic and less closely related Polyphaga
beetles such as Lycidae
or Pyrochroidae.
The adults are distinguished from other ancient weevil lineages by some characteristic traits: The fore tibia
of belines is unusual in that it has a comb of bristles (seta
e) in an apical
groove opposite the tarsal articulation; this is used for grooming
. Microscopic
ally, the spermatheca
l gland is several times longer than the spermathecal capsule. Most also have only a few (four or fewer) setae on each mandible (more in Aglycyderini
), and the pronotum is constricted at the tip (not in Oxycorynus, Parallocorynus and Rhopalotria).
The endocarina is V-shaped. In most, the antennae have a retractable membrane at the base (not in Parallocorynus and Rhopalotria), and the alimentary canal has caeca distributed all over at random (in two clean bundles in Aglycyderini
and Metrioxenini
).
; the larva
e feed on the wood of diseased or dying plants or on deadwood, flower buds or fruits. Though they may appear to be pests because of their association with plants dying off, belids tend to avoid healthy plants. They may occur as a secondary complication in plants already affected by some pest or disease however. But altogether, belids (as opposed to many other weevils) are normally harmless and can be beneficial, the adults as pollinator
s and the larvae as indicator species
for bad condition of their host plants. In Florida
for example, Rhopalotria slossoni is important in maintaining populations of the rare Coontie (Zamia pumila).
The original host plants of belids were probably Araucariaceae
, conifers which were extremely common during the time when the family evolved. Some modern genera
also feed on angiosperms, usually rather old groups like Balanophoraceae
, Myrtaceae
or Vitaceae
, on cycad
s, or on palms. The Pacific genus Proterhinus has undergone a vigorous adaptive radiation
on the Hawaiian Islands
and evolve
d to utilize a wide range of the limited diversity of plants found there.
Aglycyderini
sometimes considered a distinct subfamily. Other classifications treat the Oxycorynidae as distinct family. A prehistoric subfamily only known from Mesozoic
fossil
s are the Eobelinae
.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of weevils, called belids or primitive weevils because they have straight antennae, unlike the "true weevils" or Curculionidae
Curculionidae
Curculionidae is the family of the "true" weevils . It was formerly recognized in 1998 as the largest of any animal family, with over 40,000 species described worldwide at that time...
which have elbowed antennae. They are sometimes known as "cycad
Cycad
Cycads are seed plants typically characterized by a stout and woody trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female . Cycads vary in size from having a trunk that is only a few centimeters...
weevils", but this properly refers to a few species from the genera
Genera
Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...
Parallocorynus and Rhopalotria.
Distribution
The Belidae today have an essentially GondwanaGondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
n distribution, occurring only in the Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
–New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
–New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
region up to Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, South
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
and Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
(barely reaching North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
), some Pacific islands (notably the Hawaiian Islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
) and a few places in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. Many lineages of belids are notable for their highly relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
ual distribution; for example the Aglycyderini
Aglycyderini
Aglycyderini are a tribe of belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils...
are found in two areas on opposite sides of the Earth, with no such beetles known from anywhere in between.
Belids were more widespread during the Late Jurassic
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...
to Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...
, about , when they were found at least in Central Asia
Central Asia
Central Asia is a core region of the Asian continent from the Caspian Sea in the west, China in the east, Afghanistan in the south, and Russia in the north...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
and Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. Paleogene
Paleogene
The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic Era...
species belonging to still-living tribe
Tribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
s are known from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
and North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
.
Description
Members of the subfamily BelinaeBelinae
Belinae are a Gondwanan subfamily of beetles which belong to the belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils . The Belinae make up the bulk of the diversity of living belid genera...
are typically elongated and cylindrical. Some belines resemble other weevils, like the genus Lixus
Lixus
Lixus refers to the following things:* lixus, the Latin word for "boiled"* Lixus in Morocco* Lixus , a genus of true weevils...
of the true weevil family (Curculionidae
Curculionidae
Curculionidae is the family of the "true" weevils . It was formerly recognized in 1998 as the largest of any animal family, with over 40,000 species described worldwide at that time...
), or brentids
Brentidae
Brentidae is a cosmopolitan family of primarily xylophagous beetles also known as straight-snouted weevils. The concept of this family has been recently expanded with the inclusion of three groups formerly placed in the Curculionidae; the subfamilies Apioninae, Cyladinae, and Nanophyinae, as well...
. Others are mimetic and less closely related Polyphaga
Polyphaga
Polyphaga is the largest and most diverse suborder of beetles; the name is derived from two two Greek words: poly-, meaning 'many', and phagein, meaning 'to eat', so the suborder is called the “eaters of many things”...
beetles such as Lycidae
Lycidae
Lycidae is a family in the beetle order Coleoptera, members of which are commonly called net-winged beetles.Beetles of this family are elongated and usually found on flowers or stems. The adults of some species are nectarivores while some may have short-lived adult lives during which they may not...
or Pyrochroidae.
The adults are distinguished from other ancient weevil lineages by some characteristic traits: The fore tibia
Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...
of belines is unusual in that it has a comb of bristles (seta
Seta
Seta is a biological term derived from the Latin word for "bristle". It refers to a number of different bristle- or hair-like structures on living organisms.-Animal setae:In zoology, most "setae" occur in invertebrates....
e) in an apical
Apical
Apical, from the Latin apex meaning to be at the apex or tip, may refer to:*Apical , an anatomical term of location for features associated with the base of an organism or structure...
groove opposite the tarsal articulation; this is used for grooming
Personal grooming
Personal grooming is the art of cleaning, grooming, and maintaining parts of the body. It is a species-typical behavior that is controlled by neural circuits in the brain.- In humans :...
. Microscopic
Microscopic
The microscopic scale is the scale of size or length used to describe objects smaller than those that can easily be seen by the naked eye and which require a lens or microscope to see them clearly.-History:...
ally, the spermatheca
Spermatheca
The spermatheca , also called receptaculum seminis , is an organ of the female reproductive tract in insects, some molluscs, oligochaeta worms and certain other invertebrates and vertebrates...
l gland is several times longer than the spermathecal capsule. Most also have only a few (four or fewer) setae on each mandible (more in Aglycyderini
Aglycyderini
Aglycyderini are a tribe of belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils...
), and the pronotum is constricted at the tip (not in Oxycorynus, Parallocorynus and Rhopalotria).
The endocarina is V-shaped. In most, the antennae have a retractable membrane at the base (not in Parallocorynus and Rhopalotria), and the alimentary canal has caeca distributed all over at random (in two clean bundles in Aglycyderini
Aglycyderini
Aglycyderini are a tribe of belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils...
and Metrioxenini
Metrioxenini
Metrioxenini are a tribe of belids, primitive weevils of the family Belidae, containing about 30 species. They are only found in two widely separated areas, Southeast Asia extending to Indonesia, and South Africa...
).
Ecology
Adults usually eat pollenPollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
; the larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e feed on the wood of diseased or dying plants or on deadwood, flower buds or fruits. Though they may appear to be pests because of their association with plants dying off, belids tend to avoid healthy plants. They may occur as a secondary complication in plants already affected by some pest or disease however. But altogether, belids (as opposed to many other weevils) are normally harmless and can be beneficial, the adults as pollinator
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s and the larvae as indicator species
Indicator species
An indicator species is any biological species that defines a trait or characteristic of the environment. For example, a species may delineate an ecoregion or indicate an environmental condition such as a disease outbreak, pollution, species competition or climate change...
for bad condition of their host plants. In Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
for example, Rhopalotria slossoni is important in maintaining populations of the rare Coontie (Zamia pumila).
The original host plants of belids were probably Araucariaceae
Araucariaceae
Araucariaceae, commonly referred to as araucarians, is a very ancient family of coniferous trees. It achieved its maximum diversity in the Jurassic and Cretaceous periods, when it was distributed almost worldwide...
, conifers which were extremely common during the time when the family evolved. Some modern genera
Genera
Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...
also feed on angiosperms, usually rather old groups like Balanophoraceae
Balanophoraceae
Balanophoraceae is a subtropical to tropical family of obligate parasitic flowering plants, notable for their unusual development and obscure affinities. The family consist of 17 genera and approximately 50 species...
, Myrtaceae
Myrtaceae
The Myrtaceae or Myrtle family are a family of dicotyledon plants, placed within the order Myrtales. Myrtle, clove, guava, feijoa, allspice, and eucalyptus belong here. All species are woody, with essential oils, and flower parts in multiples of four or five...
or Vitaceae
Vitaceae
Vitaceae are a family of dicotyledonous flowering plants including the grapevine and Virginia creeper. The family name is derived from the genus Vitis...
, on cycad
Cycad
Cycads are seed plants typically characterized by a stout and woody trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female . Cycads vary in size from having a trunk that is only a few centimeters...
s, or on palms. The Pacific genus Proterhinus has undergone a vigorous adaptive radiation
Adaptive radiation
In evolutionary biology, adaptive radiation is the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. Starting with a recent single ancestor, this process results in the speciation and phenotypic adaptation of an array of species exhibiting different...
on the Hawaiian Islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
and evolve
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
d to utilize a wide range of the limited diversity of plants found there.
Systematics
The subfamilies have each, at various times, been considered as separate families, but they are grouped together in most recent classifications. There are three living main lineages, variously considered three or, as here, two subfamilies, with the tribeTribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
Aglycyderini
Aglycyderini
Aglycyderini are a tribe of belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils...
sometimes considered a distinct subfamily. Other classifications treat the Oxycorynidae as distinct family. A prehistoric subfamily only known from Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s are the Eobelinae
Eobelinae
Eobelinae are an extinct beetle subfamily that throve in the late Mesozoic. They belong to the belids or "primitive weevils" of the family Belidae. The Belidae today occur only from the Australia-New Guinea-New Zealand region to Southeast Asia, some Pacific islands, South and Central America and a...
.