Belidae

Rhinotia hemistictus

The Belidae are a family of weevils ( superfamily Curculionoidea ). The family includes 348 described species in 55 genera (excluding only fossil known ). Its distribution center is located in Australia and South America, and the Pacific Islands.

Features

The Belidae are among the most morphologically primitive weevil families with straight, not geknieten sensors ( " Orthoceri "). The body shape is between the two subfamilies very different and even within very different diverse. The Belinae are elongated, walzliche beetles Oxycoryninae usually flat. Some species have striking, backward extended in lace or spined elytra. Some Australian species imitate in body shape toxic Rotdeckenkäfer the genus Metriorrhynchus, South American species of the genus Homalocerus have drawing patterns that are reminiscent of toxic Lampyridae ( Bates'sche mimicry ). The various groups that were previously divided into three (or even four) families of their own, are held together only by a few autapomorphe features. The monophyly of the family is primarily based on features of the larvae. When the beetles itself is on the underside of the head, a triangular, two seams edged sclerite, the " Gula " characteristic. A Gula is in many beetle families with outstretched head available ( plesiomorphes feature ), with nearly all other weevils ( with the exception of some Nemonychidae ) it is shifted to the head inside either, so externally only one seam is visible, or even merged completely. More plesiomorphic features are the possession of two spurs on the center and rear rails, partly also on the front rails, and five free, unfused abdominal plates ( sternites ) of approximately the same length on the abdomen. However, in contrast to the Nemonychidae and Anthribidae they have no free labrum at the proboscis tip. On the rails ( tibiae ) of the front legs always sits a characteristic groove or depression with trimming of stiff bristles, which serves as the antennas - cleaning system. There are types before with moderately long and thin, curved trunk, with others it is greatly shortened and hardly recognizable ( Tribus Aglycyderini ). The probe sitting at the trunk base or trunk center. The antennas contribute to Belinae no leg, or if it is loosely structured and hardly withdrawn from the sensor scourge. The Oxycoryninae other hand, have a clear and compact leg with two fused limbs. The eyes protrude in all types hemispherical front of the head contour. The forehead between them is mostly of trunk width.

Larvae

The larvae of Belidae are typical weevil larvae, which, with the exception of the head capsule hardly sclerotized and weichhäutig, mostly white-colored and curled. They are usually incurved ventral C-shaped and legless. The larvae are usually more bristles than those of Curculionidae. Special features of the family include: The head is permanently withdrawn something in the trunk. The antennae are short and unsklerotisiert, they act in two parts by a retractable membrane. Outside there are two strongly sclerotized bars on the labrum. At the sclerotized head capsule, the frontal sutures are regressed. The Belinae the rear edge of the pronotum is expanded and extended to the rear.

Way of life

Most Belidae live as larvae inside of ailing or dead twigs of woody plants. The most primitive types are bound to conifers. In Australia, most of the species of the subfamily Belinae instead occur at (real) acacia ( Acacia species ). Many South American species should be bound by ferns. Others live in cones of Araucaria.

Have become known especially some South and Central American species that are bound to cycads. Two species of the genus Rhopalotria each monophagous disseminated to a Palmfarnart the genus Zamia, one of these types comes up in the southern United States (Florida ) before. The weevils are looking catkins on ( strobili ), where they only accept fresh developing, which are characterized by the rapid growth by heat. The beetles fight to access and possess specially reshaped front legs. When flying from a kitten to the next, they transport pollen on the body surface, which fertilizes the plant. The females lay eggs in a blown-out niche of a male kitten, the larva develops in its interior. The Sago Palm is dependent on the beetles for pollination, wind pollination does not occur.

System

The Belidae family in the current definition has been definitively established by Adriana Marvaldi until 2004, but is widely accepted as today. Most of the older writers understood under this name today subfamily Belinae. The species of the subfamily Oxycoryninae were depending on the author, as an independent families Oxycorynidae, Aglycyderidae and Proterhinidae, construed. Later cladistic analyzes have proved on the basis of the morphology of larvae and adults, as well as phylogenetic trees their togetherness. Their position within the superfamily Curculionoidea is relatively basal. They are considered as sister group of all weevils, with the exception of Nemonychidae and Anthribidae, taken together.

The family is divided into two subfamilies:

• Subfamily Belinae
• Subfamily Oxycoryninae.

Dissemination

With few exceptions, Belidae are restricted to the southern hemisphere. Most species are found in Australia and the Pacific Islands, for example, New Zealand, New Guinea and Hawaii, spread, many come alongside ago in South America. The Belinae are limited in their distribution to these regions. The Oxycoryninae show the same distribution in essence, but are more common in some places a little. The distinguished by the peculiar morphology modified Aglycyderini (formerly even as its own subfamily or even family considered ) appear completely isolated from each other on three islands / island groups: the Canary Islands, Hawaii, and New Zealand / New Caledonia. Such fragmented ( disjunct ) areas are considered to be typical of relict groups that were once widespread. Two genera ( Afrocorynus and Hispodes ) live in South Africa.

Fossils

As with most ancient, marked primarily by plesiomorphic features families safe assignment of fossil species to the family is difficult. Previously, the extinct subfamily Eobelinae was seen as the root group of the Belidae. Today the Eobelinae are seen as representatives of the still more primitive family Nemonychidae. Some species but were separated from the Eobelinae and left at the Belidae, but this assignment is uncertain. Fossil representatives of the family should be available from the Jura, from the deposit Karatau in Kazakhstan and the chalk, from the deposit Montsec in Spain. In Bernstein they are apparently rare. A species was described from Cretaceous amber from France.