Borsoniidae
In 2011, Bouchet et al. brought some genera from the subfamilies Clathurellinae and Raphitominae (previously placed in the family Conidae), as well as genera from the subfamily Zemaciinae (which had been considered turrids), together to form the family Borsoniidae A. Bellardi, 1875. This re-arrangement was based on anatomical characters and a dataset of molecular sequences of three gene fragments.
This is a rather heterogeneous group. Bouchet et al. considerd the family to be not fully resolved as it was based on molecular data and comprises rather conchologically different clades. They suggested this could be explained by the fact that many taxa in this group are among most ancient of conoideans, known since the Palaeocene (Zemacies, Borsonia, Tomopleura) or Eocene (Bathytoma, Genota, Microdrillia).
The names Borsoniinae Bellardi, 1875, and Pseudotominae Bellardi, 1875, were established simultaneously. As First Revisers, under Art. 24 of the ICZN Code, Bouchet, Kantor et al. gave precedence to the former over the latter.
Based on a single taxa Abdelkrim et al. 2018 found the borsoniids to be sister to a clade containing the Mitromorphidae, Raphitomidae, Mangeliidae, and Clathurellidae (a finding that does not disagree with other previous incomplete studies i.e. Uribe et al. 2017)
Shell small to large (5–80 mm), fusiform to biconic, sometimes with strong to obsolete columellar pleats. Sculpture usually well developed, axial ribs sometimes obsolete to absent. Siphonal canal short to moderately long. Anal sinus on subsutural ramp, deep. Protoconch when multispiral with up to five whorls, initially smooth and then with arcuate axial riblets, when paucispiral up to two smooth whorls.
In living taxa:
Operculum with terminal nucleus, fully developed to missing. Radula of hypodermic marginal teeth that usually have a weakly developed solid basal part, often attached to the ligament. Tooth canal opening (sub)terminally or, sometimes, laterally. At their tip teeth can have weak to rather strong barb(s). Overlapping of the tooth edges is weak. In Zemacies however, the radula is completely absent.