Haplotaxidae

Erséus, Christer, Williams, Bronwyn W., Horn, Kevin M., Halanych, Kenneth M., Santos, Scott R., James, Samuel W., Châtelliers, Michel Creuzé des & Anderson, Frank E., 2020, Phylogenomic analyses reveal a Palaeozoic radiation and support a freshwater origin for clitellate annelids, Zoologica Scripta 49 (5), pp. 614-640 : 633

4.3.4 | Haplotaxidae sensu lato

This is an assemblage of freshwater clitellates with a complex taxonomic history and a distribution covering all continents except Antarctica. It comprises ca. 20 species in eight genera ( Martin et al., 2007 %, occasionally suggested to represent an ancestral stage in clitellate evolution as a whole (e.g. Brinkhurst, 1992 %, but more recently recovered as a non-monophyletic taxon close to the base of Crassiclitellata ( Anderson et al., 2017; Martínez-Ansemil et al., 2012%. In the present study, we included transcriptomes of three species, that is, data also used by Anderson et al.; two of those species, but with other data, were treated by Martínez-Ansemil et al. The conclusion that Haplotaxidae as currently defined is not monophyletic is maintained. We found Haplotaxis (= Haplotaxidae sensu stricto), with maximum support, as sister to the lineage containing Lumbriculata, Moniligastridae , Crassiclitellata and the two other ‘haplotaxids’ ( Delaya and Pelodrilus % (Figures 1–3%. In the present study, Delaya and Pelodrilus are outside, but close to, Crassiclitellata (as currently defined; see below%, but this is not maximally supported. In Anderson et al. (2017, Figure 1%, on the other hand, they are in paraphyly, that is, adjacent to each other, and with full support. However, our representation of Haplotaxidae s. lat. is limited, and a final conclusion must be based on molecular data from a much larger sample of taxa. In an ongoing study using legacy markers, a greater number of samples of alleged haplotaxids from North America, Europe, Asia, Africa and Australia will be assessed in more detail (Martinsson, Fend, Klinth, Martin, Torii, Erséus, in prep.%.