Crypturellus cinnamomeus, the thicket or rufescent tinamou, is a quail to partridge sized bird from the lowlands of Central America. In fact, the vernacular names for Tinamous are often names such as 'perdiz' or 'codorniz/godorniz' meaning 'partridge' or 'quail' respectively in the local Spanish dialects.

It is one of some forty species of tinamiform birds found in South and Central America.

The binomial 'Crypturellus cinnamomeus' is a mixture of Greek roots and Latin endings meaning 'little cinnamon coloured hidden one'.

The Tinamiformes share certain affinities with the group of birds defined as 'paleognaths' (e.g., kiwi, moa, elephant bird), but their relations to or within the paleognathes are unresolved as the very definition of the group 'paleognath' is inconsistent and somewhat contentious in the field of avian systematics.

Unlike their paleognathous cousins, the rheas, emus, and ostriches, tinamous are volant. Although possessed of the capabilities of flight, these birds do not have a great command of that ability. The naturalist W. H. Hudson, exploring the pampas of Argentina late in the last century, likened tinamou flight to the motion of a brakeless engine, powerful but ungovernable.

An osteologic preparation of the tinamou Crypturellus cinnamomeus, specimen number KU-34658, comprises the focus of this morphological study. This specimen, a loan from the University of Kansas Museum of Natural History, was originally collected from El Astillero, Guatemala on the second of February 1955. First catalogued as KMNH-550212-11, it was identified as a male by its collecter, James W. Bee.

The specimen is believed to be a mature individual by virtue of the relatively high degree of ankylosis of the parietal-frontal suture. Ankylosis of this suture is known to be incomplete in even relatively mature juvenile specimens.

This specimen was scanned by Richard Ketcham and Cambria Denison in the fall of 1997. Raw data for the CT x-ray data set consists of 100 micrometer thick slices through the horizontal plane of the skull. These data were resliced into the coronal and sagittal planes with the aid of the National Institute of Health's shareware application NIH Image 1.62.

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Links

A web page featuring information on tinamous by birder Don Roberson.