New York weevil

Ithycerus noveboracensis is a Rüsselkäferart ( superfamily Curculionoidea ) from North America. The American name is " New York weevil ". The species is a taxonomically isolated relict form, about their relationships is unclear, and has been assigned by various authors have many different families. A widespread view it represents the only way in which (so monotypic ) Family Ithyceridae.

Features

The type achieved the incredible for a weevil area of ​​12 to 18 millimeters. It is including all attachments dyed black, but bears a striking formed from shed hair drawing. The elytra bear on every second gap ( between the two weevils, like many other beetles, usually pronounced dot rows ) formed from a light shed strips are interspersed in the formed of black, erect scales small spots. The tag ( scutellum ) is conspicuous by very dense bright squamation. Also on the pronotum are three longitudinal stripes of bright scales available. The beetle is elongate oval with parallel-sided forward, backward abruptly narrowed elytra with distinct front corners ( "shoulders "). The pronotum is distinctly narrower than the elytra ( about half as wide ) and narrower bell-shaped towards the front. The back is not narrowed head carries two oval, projecting from the head contour eyes. The proboscis is very short (about as long as wide, scarcely half as long as the head), flattened above, slightly widened forward ( extended) with two keels. The straight (not geknieten ) antennas sit sideways in the trunk center. You can wear a short and compact, tripartite sensor lobe. The species is conspicuous by special training of the abdomen. This acts as if he had six sclerites ( Ventrite ). However, the sixth is in reality a tergite ( pygidium ), has migrated to the ventral side. Accordingly, the anus and the genital opening is not at the body end, but shift the belly side forward.

The larva is during weevil larvae are typically completely legless by significant, zweisegmentige Torah calf A (without claw ) striking. The head capsule contributes both sides three larval eyes ( stemmata or Ocularia ). It reaches a maximum of about 25 millimeters in length and is colored white with a yellow head capsule. Your cuticle is also striking by numerous small Dörnchen ( spicules ).

Way of life

The species is bound to deciduous trees. The adult beetles feed on leaves and occasionally on young branches, flowers or buds. The larva lives in the soil and feeds on the roots. Is given a fairly wide range of food, which includes the families Betulaceae, Juglandaceae and Fagaceae. It is also passed to newly introduced by humans fruit trees ( family Rosaceae ). Most information comes from American beech and various oak species, eg Quercus alba and Quercus velutina.

The female lays its eggs in the summer in the ground, at the foot of a suitable tree species. The larvae feed externally on the roots and remove the entire cortex. Their development requires two years. They pupate in May or June of the second year.

Dissemination

The species is known from eastern North America (USA and Canada). The northern boundary of the distribution passes through Quebec and Ontario, in the west Wisconsin and Nebraska are achieved. The southern deposits are located in Georgia and Texas.

Economic Importance

The species has been occasionally reported in tree crops or orchards as harmful.

System

The position and degree of relationship of Ithycerus noveboracensis are still unknown satisfactory. The species is characterized by a mosaic of original, plesiomorphic and derived features. Plesiomorphies are, for example, straight, non geknieten antennas, the shape of the male genitalia and the shape of the mask with dual-segment legs. After cladistic analyzes of the phylogeny two different positions are proposed:

• Leads a) basal branch of the line to the weevils (in the narrow sense) ( family Curculionidae )
• B ) original group within the family Brentidae.

Many researchers prefer to include the species as monotypic subfamily Ithycerinae in the Brentidae family, even if the underlying results are anything but clear. This position will entail, among other things, that the Apioninae also a subfamily of Brentidae (and not an independent family Apionidae ) are. Because of the unclear and contradictory data available, many researchers prefer the kind, at least until a better basis exists to provide in their own family Ithyceridae. As such, they are, for example listed in the world catalog.

Swell

• Donald E. Bright ( 1993): The insects and arachnids of Canada. Part 21: The weevils of Canada and Alaska Volume 1 Coleoptera: Curculionoidea, excluding Scolytidae and Curculionidae. (Canada Communication Group ), ISBN 0-660-14433-6
• Charles W. O'Brien ( 1994): A catalog of the Coleoptera of America north of Mexico. Family: Ithyceridae. Unites States Department of Agriculture, Agriculture Handbook Number 529-146.
• A. A. Legalov (2009): A review of fossil and recent species of the family Ithyceridae ( Coleoptera) from the world fauna. Amurian zoological journal. 1 (2): 117-131.
• Brenda Μ. May ( 1993): Larvae of Curculionoidea (Insecta: Coleoptera): a systematic overview. In: Lincoln, N.Z. (editor): Fauna of New Zealand, no. Manaaki Whenua Press 28