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(invertebrate zoology)
The body division comprising the united head and thorax of arachnids and higher crustaceans.



that part of the body of arthropods formed as a result of the fusion of the cephalic and thoracic segments.

The cephalothorax is characteristic of higher crustaceans and chelicerate arthropods (Arachnida, Xiphosura, and the extinct paleozoic Eurypteridae). Among the crustaceans, the cephalothorax is formed in Decapoda by the fusion of six cephalic and seven thoracic segments. In Chelicerata it consists of the six front segments of the body (which usually bear the appendages), to which a seventh (pregenital) segment is sometimes attached.

References in periodicals archive ?
ensis from Chonburi province, both of which are significantly higher than samples of banana prawn cephalothorax from Chantaburi and Trat provinces.
It is the reduction of the eyestalk, bringing the marginal ommatidia close to the dorsal carapace of the cephalothorax, that allows the ommatidia to extend backwards to form the thoracic organ.
It should be noted that the term 'complex element' is used by that author to refer to several types of micromeric elements in Psammosteus, namely: (1) basic complex elements with the synchronomorial type of growth and (2) scales and scale-like elements with the cyclomorial type of growth, which probably come from the tail and the caudal part of the cephalothorax.
2015), and because the consumer market largely considers the abdomen and not the cephalothorax, the fact that the muscle of shrimp accumulates few nanoparticles is an advantage.
The cephalothorax constitutes half or more of the body length.
Spiders have two main body parts: The cephalothorax and the abdomen, connected by a thin waist called the pedicel.
Other ways in which arachnids differ from insects are that they have a fused head and thorax called a cephalothorax, whereas these body segments are separate in insects as they are in man; scorpions never possess wings or antennae and do not sport compound eyes.
Generally speaking, the shrimp's body is divided into two segments: the cephalothorax, which is comprised of the head and the thorax, and the abdomen.
However, variables like larval density, temperature, food and others can affect pupae cephalothorax size, making it obligatory to follow strict culture conditions so the device can effectively separate males from females (Papathanos et al.