System Glossary
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Definition of Term

(English) The supporting bony elements of fins, including spines and soft rays; all fin-supports are rays, whether segmented, unsegmented or spinous, but sometimes the term ray is used to denote soft rays only. In that sense, a ray is a flexible, rod-like segmented and often branched, bilaterally paired fin support of dermal origin. Rays may be divided into soft-rays (as just described) and hard-rays or pseudacanths which are ossified, inflexible and superficially like a spine (pseudacanths are found in some Cyprinidae, all Ictaluridae, Notacanthidae, etc.). Called dermatrichs as their origin is dermal. Ray counts are given in Arabic numerals, e.g. 11-14. Simple (rudimentary) fin rays are small, unbranched, unsegmented soft rays usually found at the beginning of a fin. Spines are unpaired and unsegmented, usually sharp and stiff rods supporting the membranes of the fins. Spine counts are given in Roman numerals, e.g. X-XII. (See also: spine, fin rays, soft ray)
(French) Éléments osseux secondaires des nageoires, y compris les colonnes vertébrales et les rayons doux ; tous les bases des nageoires sont des rayons, soit segmentés, non segmentés ou épineux, mais quelquefois le terme rayon est employé pour dénoter seulement les rayons doux. (See also: spine, fin rays, soft ray)
(Portuguese) Elementos ósseos que suportam as barbatanas (raios espinhosos e moles); a todos estes elementos se dÀo nome de raios (segmentados e não-segmentados ou espinhosos) mas normalmente designam só os raios moles (segmentados). (See also: spine, fin rays, soft ray)

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