Scorpion anatomy: 1 = Prosoma; 2 = Mesosoma; 3 = Metasoma

The metasoma is clearly visible on this ant: it is the posterior section, including the petiole

The metasoma is the posterior part of the body, or tagma, of arthropods whose body is composed of three parts, the other two being the prosoma and the mesosoma. In insects, it contains most of the digestive tract, respiratory system, and circulatory system, and the apical segments are typically modified to form genitalia. In a few of the most primitive insects (the Archaeognatha), the metasomal segments bear small, articulated appendages called "styli", which are often considered to be vestigial. There are also pre-apical appendages in most insect orders, called cerci, which may be multi-segmented and almost resembling a posterior pair of antennae; these may be variously modified, or lost entirely. Otherwise, most adult insects lack appendages on the metasoma, though many larval insects (e.g., caterpillars) have some form of appendages, such as prolegs or, in aquatic insects, gills. A petiole (also called a pedicel) is the first abdominal segment of members of the Apocrita. ... In invertebrate biology, a tagma (plural tagmata) is a specialized grouping of arthropodan segments, such as head, body, and tail. ... Subphyla and Classes Arthropods (phylum Arthropoda) (from Greek ἀρθρον, meaning joint and πούς/ποδός, meaning foot) are the largest phylum of animals and include the insects, arachnids, crustaceans, and others. ... The cephalothorax is an anatomical term used of arachnid and malacostracan arthropods for the first major body section. ... Scorpion anatomy: 1 = Prosoma; 2 = Mesosoma; 3 = Metasoma The mesosoma is clearly visible on this ant: it is the midlle section, in between the head and the petiole The mesosoma is the middle part of the body, or tagma, of arthropods whose body is composed of three parts, the other... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... To meet Wikipedias quality standards, this article or section may require cleanup. ... Human circulatory system. ... A sex organ, or primary sexual characteristic, narrowly defined, is any of those parts of the body (which are not always bodily organs according to the strict definition) which are involved in sexual reproduction and constitute the reproductive system in an complex organism; namely: Male: penis (notably the glans penis... Families Machilidae Meinertellidae The Archaeognatha are known as the bristletails, so named because of their three-pronged tails. ... A vestigial organ is an organ whose original function has been lost during evolution. ... Cercus (plural cerci) is the scientific word for certain hair-like sensory structures on some types of insects. ... Antennae (singular antenna), are the paired appendages connecting to the first (and in crustaceans also to the second) segment of the head of the members of all subphyla of the arthropods except Chelicerata. ... This article is about insect larvae. ... This article does not cite its references or sources. ... gills of a Smooth Newt Gills inside of a tuna head In aquatic organisms, gills are a respiratory organ for the extraction of oxygen from water and for the excretion of carbon dioxide. ...

In Apocritan Hymenoptera (wasps, bees and ants), the metasoma consists of the second abdominal segment (which typically forms a petiole) and those segments posterior to it, and is often called the gaster rather than referring to it as the "abdomen"; in these insects, the first abdominal segment is attached to the thorax. The metasoma is armoured with chitinous plates, on the upper surface by the tergites and on the lower surface by the sternites. Superfamilies Apoidea Ceraphronoidea Chalcidoidea Chrysidoidea Cynipoidea Evanioidea Ichneumonoidea Megalyroidea Proctotrupoidea Sphecoidea Stephanoidea Triganalyoidea Vespoidea Many families, see article Apocrita is a suborder of insects in the order Hymenoptera. ... Suborders Apocrita Symphyta Many families, see article Hymenoptera is one of the larger orders of Insects, comprising the sawflies, wasps, bees, and ants. ... WASP is a folk-sociological term for a member of the white establishment. Although the word is derived from an acronym for White Anglo-Saxon Protestant, in practice its use has expanded beyond the strict meaning of the acronym; in use, it is frequently derogatory. ... Families Andrenidae Apidae Colletidae Halictidae Megachilidae Melittidae Stenotritidae Bee collecting pollen Bees (Apoidea superfamily) are flying insects, closely related to wasps and ants. ... Ants are one of the most successful groups of insects in the animal kingdom and are of particular interest because they are a social insect and form highly organized colonies or nests, sometimes consisting of millions of individuals. ... The abdomen is a part of the body. ... Diagram of a tsetse fly, showing the head, thorax and abdomen The thorax is a division of an animals body that lies between the head and the abdomen. ... A hoplite wearing (only) a helmet, breastplate greaves and a shield. ... Structure of chitin molecule Chitin (IPA: ) is one of the main components in the cell walls of fungi, the exoskeletons of insects and other arthropods, and in some other animals. ... A tergum (pl. ... The sternum (pl. ...

In scorpions, the metasoma is the tail. Superfamilies Pseudochactoidea Buthoidea Chaeriloidea Chactoidea Iuroidea Scorpionoidea See classification for families. ...

In other arachnids such as spiders, the mesosoma is fused with the metasoma to form the opisthosoma. Suborders Spiders are predatory invertebrate animals that produce silk, and have two tagma, eight legs, no chewing mouth parts and no wings. ... Scorpion anatomy: 1 = Prosoma; 2 = Mesosoma; 3 = Metasoma The mesosoma is clearly visible on this ant: it is the midlle section, in between the head and the petiole The mesosoma is the middle part of the body, or tagma, of arthropods whose body is composed of three parts, the other... The opisthosoma is the posterior portion of the arachnids body behind the prosoma. ...