The following replacement name in Acoela (Xenacoelomorpha, Acoelomorpha) is proposed: Acoelopelophila Ceccolini & Cianferoni nom. nov. pro Pelophila Dörjes, 1968 nec Dejean, 1821. Further, the following new combination is also established: Acoelopelophila lutheri (Westblad, 1946) comb. nov.


Keywords: Acoelomorpha; homonym; new combination; nomenclature change.


Se ha detectado un homónimo más moderno entre los Acoela (Xenacoelomorpha, Acoelomorpha) y se propone el siguiente nombre sustitutivo: Acoelopelophila Ceccolini & Cianferoni nom. nov. pro Pelophila Dörjes, 1968 nec Dejean, 1821. Se da también la siguiente nueva combinación: Acoelopelophila lutheri (Westblad, 1946) comb. nov.

Palabras clave: Acoelomorpha; cambio de nomenclatura; homónimo; nueva combinación.

Recibido/Received: 09/11/2021; Aceptado/Accepted: 28/02/2022; Publicado en línea/Published online: 06/04/2022

Cómo citar este artículo/Citation: Ceccolini, F. & Cianferoni, F. 2022. A replacement name for Pelophila Dörjes, 1968 (Xenacoelomorpha: Acoela, Convolutidae). Graellsia, 78(1): e165. https://doi.org/10.3989/graellsia.2022.v78.339

  1. Abstract
  2. Resumen
  3. Acknowledgments
  4. References

Xenacoelomorpha ‍Philippe et al. 2011 is a small phylum of bilateral invertebrates recently established, removing them from Platyhelminthes (‍Philippe et al., 2011). They seem to be the sister group of the other bilateral animals (‍Rouse et al., 2016; ‍Cannon et al., 2016) and are divided in the subphyla Xenoturbellida Bourlat et al., 2006, with 6 species known (‍WoRMS, 2021), and Acoelomorpha Ehlers, 1985, including about 435 species, most of them accommodated in the order Acoela Uljanin, 1870 (‍Zhang, 2013).

We detected a homonym genus name in Acoelomorpha Acoela and herein we propose the new substitute name for it.

Replacement names

Dörjes (‍1968: 114) established the new genus name Pelophila to accommodate two new species: P. cavernosa and P. pachymorpha. Currently the name is still in use, even if both the original combinations are not still accepted. Indeed Pelophila pachymorpha is now classified in the genus Pelochildia Faubel & Warwick, 2005, whilst Pelophila cavernosa (the type species of the genus) is considered a subjective junior synonym of Pelophila lutheri (Westblad, 1946) (‍Tyler et al., 2021).

However, the name Pelophila had already been used in Zoological Nomenclature. Dejean (‍1821: 7) introduced this name to accommodate the species Carabus borealis Paykull, 1790 (Coleoptera, Carabidae) in his catalogue. Dejean’s name is still in use (‍Huber & Marggi, 2017; ‍Rees, 2021).

Therefore, Pelophila Dörjes is a junior homonym of Pelophila Dejean and, since no synonym is available, it must be replaced according to ICZN (‍1999, Arts. 60.1, 60.2). Herein we propose Acoelopelophila Ceccolini & Cianferoni nom. nov.



The new name remarks the classification of the genus in the order Acoela, adding the prefix Acoel- and the linking vowel -o- to the original name. Feminine gender.


Family CONVOLUTIDAE Graff, 1905

Genus Acoelopelophila Ceccolini & Cianferoni nom. nov. = Pelophila Dörjes, 1968 nec Dejean, 1826

Species Acoelopelophila lutheri (Westblad, 1946) comb. nov. = Pelophila lutheri (Westblad, 1946) = Aphanostoma lutheri (Westblad, 1946) = Mecynostomum lutheri (Westblad, 1946) = Praeaphanostoma lutheri Westblad, 1946 = Pelophila cavernosa Dörjes, 1968 (type species)


We thank the two anonymous referees whose comments improved the paper.



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