A standardized terminology of spines in the order Siluriformes (Actinopterygii: Ostariophysi)

Abstract A standardized terminology for the anatomy of pectoral- and dorsal-fin spines in the order Siluriformes is proposed based on an extensive literature review and direct examination of representatives of the order. The adult anatomy of the spines is described in detail. Terminology of various spine parts are reviewed and standardized, each term provided with a synonymic list organizing previous usage. Most of the structures treated have been recorded and named in the literature, but some are herein named for the first time. A quantitative approach is proposed for orienting decisions on name usage, aiming at minimizing differences between the terminology proposed and the vast amount of pre-existing literature, herein called the cost function. It is expected that this system will aid efforts in organizing the chaotic anatomical nomenclature of the appendicular skeleton in Siluriformes, and provide a solid basis for advances in comparative anatomy and nomenclature. The proposed terminology system has potential application on a number of fields that utilize information from catfish spines, ranging from taxonomy to phylogenetic systematics to paleontology and archaeology.