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240:) provide an example. The basic copepod body consists of a head, a thorax with six segments, ancestrally each with a swimming leg, and an abdomen with five appendageless segments. Except in parasitic species, the body is divided functionally into two tagmata, that may be called a "prosome" and a "urosome", with an articulation between them allowing the body to flex. Different groups of copepods have the articulation at different places. In the
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The first and simplest stage was a division into two tagmata: an anterior "head" (cephalon) and a posterior "trunk". The head contained the brain and carried sensory and feeding appendages. The trunk bore the appendages responsible for locomotion and respiration
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Tagmosis proceeded differently in different groups of arthropods, so that the tagmata are not derived from corresponding (homologous) segments, even though the same names may be used for the tagmata.
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in aquatic species). In almost all modern arthropods, the trunk is further divided into a "thorax" and an "abdomen", with the thorax bearing the main locomotory appendages. In some groups, such as
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of insects. The segments within a tagma may be either fused (such as in the head of an insect) or so jointed as to be independently moveable (such as in the abdomen of most insects).
201:: different kinds of segment are joined together into tagmata. Two thoracic segments are fused into the head; one thoracic segment is in the posterior tagma. Other kinds of
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or prosome (meaning "fore-part of body"). The posterior tagma may be called the abdomen. In those arachnids that have two tagmata, the abdomen is also called the
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In a given taxon the names assigned to particular tagmata are in some sense informal and arbitrary; for example, not all the tagmata of species within a given
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functions or anatomy. In some cases this has led to earlier names for tagmata being more or less successfully superseded. For example, the one-time terms "
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328:(meaning head), the thorax (literally meaning chest, but in this application referring to the mid-portion of the body), and the
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The development of distinct tagmata is believed to be a feature of the evolution of segmented animals, especially
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appear to have a single tagma with no obvious external signs of either segments or separate tagmata.
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to those of species in other subphyla; for one thing they do not all comprise corresponding
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Barnes, R.S.K.; Calow, P.; Olive, P.J.W.; Golding, D.W. & Spicer, J.I. (2001).
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Usually the term is taken to refer to tagmata in the morphology of members of the
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112:– τάγματα - body of soldiers; battalion) is a specialized grouping of multiple
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The development of animal form: ontogeny, morphology, and evolution
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This article is about the biology term. For the military unit, see
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142:, but it applies equally validly in other phyla, such as the
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Tagmata of an insect: head (cephalon), thorax and abdomen
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also have two tagmata but formed by different segments.
351:: in both groups the anterior tagma may be called the
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Ruppert, E.E.; Fox, R.S. & Barnes, R.D. (2004).
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262:and the other developmental genes they influence.
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467:"Body Regions: Their Boundaries and Complexity"
316:The number of tagma and their names vary among
347:, have two tagmata, as do the bodies of some
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124:unit. Familiar examples are the head, the
84:Learn how and when to remove this message
47:This article includes a list of general
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307:Tagmata and major appendages of a
53:it lacks sufficient corresponding
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518:(3rd ed.). Wiley-Blackwell.
355:(meaning head plus chest) or the
426:Ruppert, Fox & Barnes (2004)
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283:: cephalon, thorax and pygidium
251:Tagmosis is an extreme form of
516:The Invertebrates: a Synthesis
438:Ruppert, Fox & Barnes 2004
402:. Discovery Publishing House.
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541:(7th ed.). Brooks/Cole.
120:into a coherently functional
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18:Tagmata (arthropod anatomy)
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475:Cambridge University Press
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324:had three tagmata: the
68:more precise citations.
377:Arthropod head problem
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153:of the Arthropoda are
399:Biology of Arthropoda
396:D. R. Khanna (2004).
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537:Invertebrate Zoology
498:Barnes et al. (2001)
450:Barnes et al. (2001)
332:(meaning rump). The
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339:The bodies of many
463:Alessandro Minelli
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566:Arthropod anatomy
548:978-0-03-025982-1
525:978-0-632-04761-1
484:978-0-521-80851-4
409:978-81-7141-897-8
279:The tagmata of a
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74:October 2013
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365:crustaceans
361:opisthosoma
349:crustaceans
266:Terminology
236:(a kind of
197:Tagmata in
183:opisthosoma
66:introducing
383:References
343:, such as
322:trilobites
253:heteronomy
238:crustacean
211:arthropods
155:homologous
140:Arthropoda
128:, and the
49:references
341:arachnids
281:trilobite
242:Calanoida
223:arachnids
173:" of the
163:analogous
151:subphylum
118:metameres
560:Category
465:(2003).
371:See also
334:Hexapoda
330:pygidium
326:cephalon
234:Copepods
189:Tagmosis
144:Chordata
114:segments
357:prosoma
345:spiders
203:copepod
179:prosoma
175:Araneae
171:abdomen
169:" and "
159:somites
130:abdomen
110:tagmata
98:biology
62:improve
545:
522:
481:
406:
309:spider
137:phylum
126:thorax
51:, but
363:. In
260:genes
227:Mites
219:gills
102:tagma
543:ISBN
520:ISBN
479:ISBN
404:ISBN
318:taxa
181:and
100:, a
258:Hox
116:or
106:pl.
96:In
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418:^
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