Population Structure of Canarium labiatum (Röding, 1798) (Mollusca: Neostromboidae: Strombidae) on Green Island, Great Barrier Reef, Queensland

Maxwell, S. J., Rowell, M. K., Linda C. Hernandez Duran, L. C., and Rymer, T. L. (2020)


Canarium labiatum is a small gastropod of the Strombidae family that is commonly encountered in the inter-tidal zones of tropical Queensland, Australia, yet little is known of its population structure. A targeted survey of the Canarium labiatum population on Green Island, located near Cairns, Queensland, was conducted on 12 August 2015. Ninety adult specimens were collected, of which 49 were female and 41 were male. The sample demonstrated significant sexual axiallength size dimorphism, with a bias towards larger females. While we collected more females than males, this did not represent a statistically significant bias, and rather may reflect the clustering nature of the sample. In addition, there was no evidence of pseudohermaphroditism in females within the population under consideration. Interestingly, 11.1% of the sample did not show banding and brown/grey-blue maculations on a light grey shell, the typical colour pattern associated with Canarium labiatum. This paper fills a knowledge gap in Queensland’s Canarium labiatum population structure and provides a basis for a wider study into the size dynamics of Strombidae in general, but Canarium in particular. Keywords: Canarium labiatum, clustering, colour, imposex, pseudohermaphroditism, sex bias, size dimorphism.