Morphological shell variation of Zidona dufresnei (Caenogastropoda: Vollutidae) from the southern atlantic ocean

MEDINA, ALONSO; MARIA ALEJANDRA ROMERO; AUGUSTO CÉSAR CRESPI ABRIL; MAITE NARVARTE

Marine and Fishery Sciences

Inidep

Lugar: Mar del Plata; Año: 2020 vol. 33 p. 5 - 20

2683-7595

The volutid gastropod Zidona dufresnei is an important fishery resource from the southwesternAtlantic Ocean. This species exhibits strong interpopulation differences in life history features, which lead to postulatethe existence of two morphotype (?normal? and ?dwarf?). In this study, we combine and compare traditional and geometricmorphometrics to capture shell shape variation of Z. dufresnei among three populations from Mar del Plata (37°S) to San Matías Gulf (42° S) to test the hypothesis that the phenotypic variation already described in the life cycle andsize is also expressed in the shell shape. Significant differences in the shell morphology among these three populationswere detected, mainly associated to the maximum size of individuals and shell shape. The Bahía San Antonio morphotypehad shells with higher general roundness and weight compared to San Matías Gulf and Mar del Plata morphotypes,which were not differentiated. Our results support the hypothesis of Lahille (1895) who distinguished the morphotypeof Bahía San Antonio (?dwarf? morphotype) as Voluta angulata affinis. The functional significance of the variabilityfound is discussed in terms of the ecological and genetic effects on shape and size.