Pictured: Phylogeny and morphogeny of deep-sea gastropods of the Raphitomidae family in the South of Australia
Although the Raphitomidae family is the dominant component of gastropod communities in the deep-water regions of the World Ocean, their taxonomy is still poorly understood. Focusing on the southeast of Australia, scientists from the A.N. Severtsov Institute of Ecology and Evolution of Russian Academy of Sciences, the Australian Museum of Natural History (Sydney), the Museum of Natural History of France (Paris) have collected the most complete sample of Raphitomidae to date. On behalf of Russia, Alexander Ernstovich Fedosov, Candidate of Biological Sciences, Researcher of the Laboratory of Morphology and Ecology of Marine Invertebrates, IEE RAS, participated in the study.
Based on the morphological and molecular data obtained as a result of the study, specialists reconstructed the phylogeny of Raphitomidae and applied it to determine the genera of the family. The results for the fauna of South Australia show a large number of undescribed taxa - eleven genera and their type species are described as new to science. This study shows that the study of morphological features alone is rarely sufficient to accurately determine the species. As a result of the previously dominant conchological approach to the taxonomy of molluscs, some of the traditionally diverse genera of Raphitomidae (such as Gymnobela) are in fact artificial associations of unrelated, mostly undescribed lineages of the generic level. The observations of scientists confirm that similar morphologies of shells and radular elements observed at the genus level do not depend on phylogenetic relationships.
The study concluded that the deep-water plains of southern Australia are a hot spot for Raphitomidae diversity and an area of high endemism.
Criscione, F., Hallan, A., Puillandre, N. & Fedosov, A. E. 2021. Where the snails have no name: A molecular phylogeny of Raphitomidae (Neogastropoda: Conoidea) uncovers vast unexplored diversity in the deep seas of temperate southern and eastern Australia. Zoological journal of the Linnean Society. 191(4): 961-1000.