The thorax is made of three fused segments, the prothorax, mesothorax, and metathorax, each with a pair of legs.
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The anterior segment, closest to the head, is the prothorax, with the major features being the first pair of legs and the pronotum.
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The thorax has six segmented legs-one pair each for the prothorax, mesothorax and the metathorax segments making up the thorax-and, if present in the species, two or four wings.
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In turn, the notum of the prothorax is called the pronotum, the notum for the mesothorax is called the mesonotum and the notum for the metathorax is called the metanotum.
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The anterior part of an insect's thorax; bears the first pair of legs
The anterior of the three thoracic segments.
The second or intermediate region of the insect body bearing the true legs and the wings, made up of three rings, named in order, pro-, meso-, meta-.
Anterior and wider portion of thorax when it is divided into prothorax and narrower, posterior opisthothorax, as seen in some Redlichiida.
The front part of an insect thorax which includes the attachment points for the front legs
The frontal segment of an insect's thorax. The upper surface is generally protected by an armoured section, the pronotum, which is important diagnostically feature in some groups. In beetles, the pronotum is expanded to protect the entire thorax.