Scientific Classification
| Kingdom: Animalia |
| Phylum: Arthropoda |
| Class: Trilobita |
| Order: Phacopida |
| Family: Homalonotidae |
| Genus: Dipleura |
| Species: Dipleura dekayi Green, 1832 |
Information
Geological Range
Paleogeographic Distribution
Stratigraphic Occurrences
| Hamilton Group |
| Traverse Group |
| Floresta Formation |
References
Cooper, G. A. 1935. Young stages of the Devonian trilobite Dipleura dekayi Green. Journal of Paleontology 9:3-5.
Maria Da Gloria Pires De Carvalho. 2018. Occurrence of Dipleura dekayi Green, 1832 (Trilobita; Homalonotidae) in the Devonian of Colombia. American Museum Novitates 2018:1-8.
Stumm, E. C. 1953. Trilobites of the Devonian Traverse group of Michigan. Contributions from the Museum of Paleontology, University of Michigan 10(6):101-157.
Green, J. 1832. A monograph of the trilobites of North America: with coloured models of the species. J. Brano, Philadelphia, p. 41
Description
From Green (1832): “Shield lunate, punctate; abdomen with fourteen double, barely lobed joints; tail suborbicular; limb broad, convex, very entire; eyes obliquely deflexed. The buckler is subtriangular, and covered with granulations...The cheeks are very prominent, and swell up gradually towards the oculiferous protuberances, which are oblique, and marked at their apex with a depression, as to give them an annular appearance. The abdomen is crossed by fourteen double distinct articulations, not interrupred in their course, by the two longitudinal furrows, so common in most of the trilobites; but owing to certain curves or irregularities in the ribs near their lateral termination, a trilobate appearance may in some specimens be detected. Tail suborbicular, covex, and covered with a thick epidermis.”
From Stumm (1953): “Adult D. dekayi is a large and unique trilobite, averaging about 6 inches in length but attaining 9 inches in individual examples. The most characteristic features of the genus, of which D. dekayi is the type species, are the absence of segmentation of the glabella, loss of the thoracic axial lobe, and complete loss of segmentation and annulation of the pygidium. Young specimens resemble Calymene strongly in having the axis well developed on the thorax and tail and in having a strongly segmented glabella.”
Remarks
From Wilson (2014, p. 203): “Elongate, tongue-shaped trilobite, with nearly straight lateral margins. Cephalon broadly subtriangular, nearly twice as wide as long. Pygidium also subtriangular, with length and width subequal. Surface marked by large pores. This is one of our largest trilobites.” Maximum size 100 mm.
Online Resources
Media
Images
3D Models
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