David Reid (Zoology) has published the fourth and final monograph of the worldwide tropical periwinkle genus Echinolittorina which concludes a taxonomic review of all 60 species of this littoral gastropod mollusc.
This completes a 20-year project, which has required collection of anatomical and molecular samples from across the globe, study of all major museum collections and a 3-year NERC-funded molecular programme (by PDRA Suzanne Williams, now also a Researcher in Zoology). The recognized species diversity has been increased by about 50% and 14 new species have been described.
A scanning electron micrograph of a portion (3 tooth rows from a lotal length of 5 mm) of the long radula ribbon of Echinolittorina placida.
As a result the group is now among the most comprehensively known of all marine invertebrates, with taxonomy, morphology, development, distribution and molecular phylogeny all described in detail. It has become a model system for the study of the evolution of tropical marine invertebrates in shallow water, and has been used, for example, to demonstrate the prevalence of allopatric speciation (speciation following geographical separation of populations), the Miocene origin of many extant species, the influence of tectonic activity on diversification, and evolution of mating signals by reinforcement.
More information on an example of the group, Echinolittorina placida, is found on the NHM species of the day pages.
Reid, D.G. (2011) The genus Echinolittorina Habe, 1956 (Gastropoda: Littorinidae) in the eastern Atlantic Ocean and Mediterranean Sea. Zootaxa 2974 1–65