Haplocaulus conosomus (Stokes, 1889)

= Vorticella conosoma Stokes, 1889

= Vorticella conesoma France, 1897

Report as epibiont on rotifers: Reported as Vorticella conosoma Stokes, 1889 attached to the gelatinous tubules of the rotifer Conochilus volvox from USA (Stokes 1889). This species was reported as Vorticella conosoma Stokes, 1889 on mucus of rotifer Conochilus unicornis from France (Faure-Fremiet 1948) and from the Netherlands (De Graaf 1953; Green 2012); on Conochilus hippocrepis from Germany (Kahl 1930); on Conochilus sp. from Germany (Schödel 2018). Gajewskaja (1933) observed the species (under the name Vorticella conesoma Stokes) on Conochilus sp. from lake Baikal (Russia). France (1897) has registered the species (under the name Vorticella conesoma) in Lake Balaton (Hungary), but without mention of the host or substrate.