The “Bothropoma” species in the Red Sea

Abstract

The use of the genus Bothropoma for Red Sea colloniid species is incorrect. Of the four presumptive Red Sea species one of them usually indicated as Bothropoma bellula (H. Adams, 1873) is not a Colloniinae but probably belongs to the subfamily Liotopomatinae and is here considered a junior synonym of Depressipoma (?) pentegoniostoma (Carpenter, 1856). The shells of the other species are to be attributed to the genus Neocollonia and are very variable, but in general they can be distinguished on the basis of the development of three major spiral cords of the body whorl: Neocollonia pilula (Dunker, 1860) has a rounded profile without any protruding spiral cord and Neocollonia isseli (Thiele, 1924) has a rounded/angulated shell mainly with first spiral cord here termed number 1 protruding. These two Neocollonia may even be extreme morphs of the same species, but only molecular investigation will allow testing this hypothesis. Neocollonia munda (H. Adams, 1873) has a slightly flattened body whorl with similarly prominent spiral cords here named number 2 and 3. I consider the recently described species Neocollonia diversicolor, N. splendida and N. kantori (all Poppe Tagaro & Huang, 2023) within the intraspecific variation of N. pilula and thus junior synonyms.