First records of coalescence and hypomerism in Tonicia atrata (Polyplacophora, Chitonidae) in the southwestern Atlantic Ocean

The first cases of anomalies in the number of shell-plates in Tonicia atrata (Sowerby II, 1840) are herein reported on the basis of three specimens from Zaratiegui Bay, Tierra del Fuego, Argentina (54°50’53’’ S, 68°29’7’’ W): two cases of coalescence (one symmetrical and another one asymmetrical) an...

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Detalles Bibliográficos
Autores: Guillén, Camila, Urteaga, Diego
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/111314
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/111314
Access Level:acceso abierto
Palabra clave:Ciencias Naturales
Teratology
Morphology
Mollusca
Argentina
Patagonia
Teratología
Morfología
Descripción
Sumario:The first cases of anomalies in the number of shell-plates in Tonicia atrata (Sowerby II, 1840) are herein reported on the basis of three specimens from Zaratiegui Bay, Tierra del Fuego, Argentina (54°50’53’’ S, 68°29’7’’ W): two cases of coalescence (one symmetrical and another one asymmetrical) and a case of hypomerism. The abnormal specimens bore less ctenidia than physiological conspecific specimens of similar size. The symmetrical coalescent specimen and the hypomeric individual were significantly wider (higher width/length ratio) than physiological specimens. Nevertheless, the reported abnormalities seem to have no effect on general growth, since the body size of the abnormal specimens were close to the largest physiological ones found in the same locality.