Case 3849 – Emplectonematidae Bürger, 1904 and Emplectonema Stimpson, 1857 (Nemertea, Monostilifera): proposed conservation of current usage by reversal of precedence of the family name with respect to Eunemertidae Joubin, 1894 and designation of a new type species for the genus

Abstract

The purpose of this application, under Articles 23.9.3, 41, 65.2, and 70.2 of the Code, is to conserve the current usage and year of priority of the name Emplectonematidae Bürger, 1904 for a family of ribbon worms by reversing its precedence with respect to a senior synonym, Eunemertidae Joubin, 1894, and to conserve the current concept and usage of its type genus, Emplectonema Stimpson, 1857, by designating Emplectonema viride Stimpson, 1857 as the type species. In preparation for these rulings, a common type species, Nemertes gracilis Johnston, 1837, is designated herein for the nominal genera Nemertes Johnston, 1837 (a largely neglected junior homonym of Nemertes Cuvier, 1816) and Eunemertes Joubin, 1894, thereby rendering the latter an objective junior synonym of the former and of its valid substitute name. The type species of Nemertes Cuvier, 1816 was excluded from Nemertidae sensu McIntosh, 1874 and sensu Hubrecht, 1879, which, having been recognized as a valid grouping by later authors, required a new name. Of the two available candidates, Eunemertidae Joubin, 1894 has been almost unused since the 1900s, whereas Emplectonematidae Bürger, 1904 has been in universal use since its proposal. The latter name has an uncertain date of priority; 1874, 1894 or 1904, depending on whether and how Art. 40.2 applies to it. Emplectonema viride Stimpson, 1857, or its senior synonym Emplectonema gracile (Johnston, 1837), has universally been regarded as the type species of Emplectonema since the 1950s; however, two overlooked fixations in 1892 and 1893 of Borlasia camillea Quatrefages, 1846 as the type species of this genus now threaten the stability of nemertean genus- and family-level taxonomy.