''Odontochile'' is a genus of

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...

s in the order

Phacopida Phacopida ("lens-face") is an order of trilobites that lived from the Late Cambrian to the Late Devonian. It is made up of a morphologically diverse assemblage of taxa in three related suborders. Characteristics Phacopida had 8 to 19 thoraci ...

, family Dalmanitidae.Struve, W. Suborder Phacopina, p. O471-O472. ''in'' Moore, R.C. (ed.).

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and co ...

. Part O – Arthropoda (Trilobitomorpha). 1959 These trilobites were fast-moving low-level epifauna and detritivore. They lived in the Devonian period, from 414 to 391 million years ago.

Distribution

Silurian of China; Silurian to Devonian of Australia and the United States; Devonian of Algeria, Canada, the Czech Republic, France, Germany, Kazakhstan, Morocco and Spain.

Description

''Odontochile'' is genus of

s with a large (about long), moderately vaulted

exoskeleton An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton (endoskeleton) in for example, a human. In usage, some of the ...

with an inverted egg-shaped outline (about 1.6× longer than wide). Its headshield (or cephalon) is semicircular, with long (genal) spines extending from the side of the cephalon back to the tailshield (or

pygidium The pygidium (plural pygidia) is the posterior body part or shield of crustaceans and some other arthropods, such as insects and the extinct trilobites. In groups other than insects, it contains the anus and, in females, the ovipositor. It is compo ...

). The frontal margin of the cephalon is semicircular to parabolic, and lacks an anterior extension. The facial suture lies in front of the preglabellar furrow. The frontal lobe of the central raised area of the cephalon (or

glabella The glabella, in humans, is the area of skin between the eyebrows and above the nose. The term also refers to the underlying bone that is slightly depressed, and joins the two brow ridges. It is a cephalometric landmark that is just superior to ...

) is much wider than the other lobes. The frontal lobe is vaulted. The eye is very large, almost touching the lateral and the posterior border furrow. The eye lobe is much higher than the glabella. The "seem" that is visible from the

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

side (or doublure) is wide and flat, and has a deep and wide. The "palate" (or hypostome), also only visible from the ventral side, is elongated subtriangular (about 1½× wider than long) and adorned with three prominent spines at its back rim, and two weaker ones more to the side. To the front the hypostome has robust wings extending sideways. The thorax consists of 11 segments. The tips of the segments are leaf-shaped, pointed and angle back at about 30°. The pygidium is large, subtriangular, and about ⅔-¾× as long as wide. The axis is vaulted and 20-25% of the width of the pygidium and consists of 16-20 rings. 13–14 deep and wide pleural furrows have flat or only slightly concave bottoms. The furrows within each pleural rib (or interpleural furrows) are very narrow. The frontal band of each pleural rib is more vaulted and broader than the rear band. The pleural furrows stay clear of the margin by a distance comparable to that of length (measured along the midline) of an axial ring. The pygidial termination (or mucro) is vaulted and more or less pointed into a short broad-based spine; in derived species this spine is longer. The entire exoskeleton is covered in fine and coarse granules.

Differences with related genera

'' Reussiana'' is much like ''Odontochile'', but has a much flatter exoskeleton, 17-21 pygidial axial rings, 15-18 pleural furrows and lacks a medial terminal spine. '' Zlichovaspis'' has a subtriangular cephalon with a short median processus, a subtriangular pygidium, and a longer medial terminal spine. In '' Zlichovaspis (Devonodontochile)'' the anterior median processus is tongue-shaped, the terminal spine is even longer and slimmer, and uniquely, all elevated parts are perforated by large pores. '' Dalmanites'' has genal spines that extend to the 8th thorax segment from the front. The facial suture (almost) coincides with the frontal glabellar furrow. Eye smaller, staying clear of the lateral and posterior border furrows. The hypostome is about as wide as long with three blunt denticles. Tips of the thorax segments point increasingly further backwards as these are situated nearer to the pygidium with the last one pointing parallel to the midline. The pleural furrows of the pygidium almost touch its margin.

Taxonomy

Species previously assigned to ''Odontochile''

* ''O. branisi'' = '' Francovichia branisi'' * ''O. rugosa'' = '' Zlichovaspis rugosa''

Genera that may be confused with ''Odontochile''

* '' Odontocheila'', a genus of beetles

References

BiolibPaleobiology Database
*Sepkoski, Jac
Sepkoski's Online Genus Database – Trilobita
!--- possible source for extension of this article: http://www.geology.cz/bulletin/fulltext/bullgeosci200801001.pdf---> {{Taxonbar, from=Q7077936 Devonian trilobites of Africa Phacopida genera Trilobites of Africa Devonian trilobites of Asia Devonian trilobites of North America Silurian trilobites of Asia Silurian trilobites of North America Paleozoic life of Ontario