Anthocephaliidae

Ruhnke, Timothy R., Caira, Janine N. & Cox, Allison, 2015, The cestode order Rhinebothriidea no longer family-less: A molecular phylogenetic investigation with erection of two new families and description of eight new species of Anthocephalum, Zootaxa 3904 (1), pp. 51-81 : 76

Anthocephaliidae n. fam.

Diagnosis. Scolex with 4 bothridia; bothridia with marginal and/or one or more rows of facial loculi; apical sucker and conspicuous anterior/posterior orientation of bothridia present; myzorhynchus lacking in adult stage. Postvaginal testes lacking. Vitelline follicles interrupted by ovary. Parasites of Myliobatiformes and possibly also Torpediniformes .

Type genus. Anthocephalum Linton, 1891 . Additional genera: New genus 1, New genus 2, and New genus 4 of Healy et al. (2009) and Caira et al. (2014); possibly also Cairaeanthus Kornyushin & Polyakova, 2012 and Pararhinebothroides Zamparo, Brooks & Barriga, 1999 .

Remarks. This family differs from the Echeneibothriidae in that the myzorhynchus does not persist into the adult stage. It differs from the Rhinebothriidae in that its bothridia exhibit, rather than lack, a clear anterior/ posterior orientation that typically is manifested as an apical sucker. Furthermore, rather than one or two columns of facial loculi extending essentially throughout the length of the bothridia, it bears marginal loculi or at least one row of multiple facial loculi. It further differs from most members of the above two families in that its vitelline follicles are interrupted by the ovary. While three of the five genera (New Genus 1, New Genus 2, and New Genus 4) assigned to this family have not yet been formally described, based on information currently available on their morphology (see Healy 2006) all three are fully consistent with the diagnosis presented above.

Cairaeanthus is only provisionally assigned to this family because based on Kornyushin & Polyakova (2012) it does not fully conform to the diagnosis presented above. It exhibits large numbers of marginal loculi but is described as lacking an apical sucker. However, in working with Anthocephalum species that exhibit large numbers of marginal loculi, it has been our experience that the apical sucker is often difficult to detect. We believe Cairaeanthus may ultimately be found to possess this feature. The vitelline follicle condition of this taxon, which is described as interrupted by the ovary, is consistent with the family diagnosis, but that does not appear to be the case in the figures presented by Kornyushin & Polyakova (2012) (figs. 4, 8), which show vitelline follicles extending lateral to the ovary on both sides of the proglottid. Examination of additional material and inclusion of this taxon in molecular analyses will do much to illuminate the placement of this genus.

At this time we have provisionally also assigned Pararhinebothroides Zamparo, Brooks & Barriga, 1999 to the Anthocephaliidae despite the fact that, as described by Zamparo et al. (1999), it appears to lack the clear anterior/ posterior orientation of the bothridia diagnostic of the family. The proglottid anatomy of its only known species, Pararhinebothoides hobergi Zamparo, Brooks & Barriga, 1999 , is fully consistent with that of the family, and specifically with Anthocephalum . Material of Pararhinebothroides preserved for molecular work was unavailable for inclusion in our molecular analysis but it would be interesting to pursue its placement in a molecular context. It would also be useful to pursue the question of an apical sucker using scanning electron microscopy.