Canarium wilsonorum is a species with a couple of distinct growth forms in the Marshall Islands that live in different habitats. Specimens from rubble and under rocks on seaward reef in 10 to 25m of water are small, short, and rather squat. The larger population that lives in shallow lagoon Halimeda beds have shells that tend to be much larger, narrow, and elongate. Although the larger seaward reef specimens may match the smaller lagoon specimens in length, those from the lagoon seem distinctly narrower and more elongate. It almost seems as though we are looking at two different species. Both forms are highly variable in color. The first three specimens below came from the seaward reef. According to Liverani et al (2021), this should revert back to Canarium wilsoni.
The rest of the living animals are from lagoon Halimeda patches.
A hermit crab has taken over the yellow shell below.
The first five sets of empty shells below are from lagoon Halimeda patches.
The next set is a specimen from the seaward reef.
This lagoon specimen is probably C. wilsonorum, but more developed axial ribs that we typically see.
Created 1 October 2009
Updated 30 July 2024