Wiegmann Triton Shell, Monoplex wiegmanni
Wiegmann Triton Shell, Monoplex wiegmanni. Shell collected off the beach of Punta Chivato, Baja California Sur, May 2023. Size: 8.7 cm (3.4 inches) x 5.1 cm (2.0 inches). Collection, photographs and identification courtesy of Colin Campbell, DVM, Punta Chivato.
Phylogeny: The Wiegmann Triton Shell, Monoplex wiegmanni (Anton, 1838), is a gastropod mollusk that is a member of the Cymatiidae Family of Triton Shells. The genus Monoplex is one of twenty-three genera in this family, and there are twenty-seven species in this genus.
Description: The Wiegmann Triton Shell is thick and heavy with a spindle-shaped outline. The shell is sculpted with widely spaced varices on the spire, a few nodes on the shoulders of the whorls, and a spiral structure of uniformly wide ribs. The columella is curved. The aperture is large with a thickened outer lip, which marked by several folds that extend inside the aperture. Unfortunately, the above photographed specimen is broken and the outer lip is missing. The exterior of the shell is yellowish brown with the spiral ribs being darker than the interspaces. Wiegmann Triton Shells reach a maximum of 8.7 cm (3.4 inches) in length and 5.1 cm (2.0 inches) in height established by the shell photographed above.
Habitat and Distribution: Wiegmann Tritons are found on rocks from the intertidal zone and at depths to 118 m (387 feet). They are a subtropical to tropical Eastern Pacific species that are found in all Mexican waters of the Pacific Ocean with the exception that they are absent from north of the San Ignacio Lagoon, Baja California, along the central and northwest coasts of the Baja Peninsula.
Ecology and Behavior: Wiegmann Triton are a poorly studied and understood species. There is very limited documentation of their diet, predation, reproduction or ecosystem interactions. Other species in the Cymatiidae Family are predators that feed primarily on ascidians, bivalves, gastropods, sea cucumbers, sea stars, and urchins. They sense their prey with chemoreceptors and utilize chemicals in their saliva to anesthetize and pre-digest their prey. Wiegmann Tritons are gonochoric and reproduce sexually. Some sources state that they reproduce through broadcast spawning, with external fertilization, and other sources state they have internal fertilization. Triton species are generally known for having a long larval phase. Consequently, they can drift, as plankton, for long distances before settling to the bottom. Their engagement in any type of commensal, parasitic, or symbiotic relationships has not been formally documented. From a conservation perspective the Wiegmann Triton has not been formally evaluated.
Synonyms: Fusus wiegmanni, Linatella (Linatella) wiegmanni, Triton perforatus and Tritonium nodosum.