Modiolus aurum Osorio from Juan Fernandez Archipelago, Chile (Mollusca: Bivalvia: Mytilidae)

This dataset is from Cecilia Osorio R. (1979) paper on Modiolus aurum, spec. nov., Osorio from Juan Fernandez Archipelago, Chile.

In 1970 Osorio received 21 specimens of Modiolus from Juan Fernandez Archipelago. Specific identification was not possible, because of encrusting epizoans. In 1973 another sample of 97 specimens came in, not only without epizoans, but more representative and in better condition. Some additional specimens then were noted in the collections of the National Museum of Natural History of Santiago.

Odhner (1922) cited "Modiola plumescens Dunker, 1868" as occurring on Juan Fernandez Island, but Soot-Ryen (1959) suggested that until confirmed by further collecting this species should not be included in Chilean faunal lists. The specimen mentioned by Odhner as in the Stockholm Museum seems now to be missing. However, other specimens, from Australia, determined by Odhner as M. plumescens, were available on loan. Also examined material from lie Nou and Broome, Australia, now in the Museum of Paris. The type locality of Dunker's species is Samoa, Viti-Ins, Uvea

Because Odhner had only a single specimen from Juan Fernandez on which to base his determination of "Modiolus plumescens" misidentification is understandable. The 2 forms have a similar outline. As a result of the comparative study, it is concluded that there are 2 distinct species. For the Juan Fernandez form, which is therefore considered to be undescribed, the name Modiolus aurum is proposed, in reference to the golden colour of the shell.