European Journal of Protistology 48 (2012) 48–62 Redescription of Licnophora chattoni Villeneuve-Brachon, 1939 (Ciliophora, Spirotrichea), associated with Zyzzyzus warreni Calder, 1988 (Cnidaria, Hydrozoa) Inácio Domingos da Silva-Neto a,∗ , Thiago da Silva Paiva a , Roberto Júnio Pedroso Dias a , Carlos José Alexandre Campos b , Alvaro Esteves Migotto c a Laboratório de Protistologia, Departamento de Zoologia, Instituto de Biologia, CCS, Universidade Federal do Rio de Janeiro UFRJ, CEP: 21941-590 Ilha do Fundão, Rio de Janeiro – RJ, Brazil b Centre for Environment, Fisheries and Aquaculture Science (Cefas), UK c Centro de Biologia Marinha/CEBIMar, Universidade de São Paulo, São Sebastião – SP, Brazil Received 30 September 2010; received in revised form 20 July 2011; accepted 21 July 2011 Available online 16 September 2011 Abstract Licnophora chattoni, found in association with Zyzzyzus warreni, a tubulariid hydroid epizoic in sponges from São Sebastião (SP, Brazil), is redescribed and illustrated using light and electron microscopy. The ciliate has a flexible, transparent body formed by an oval anterior region linked to the posterior basal disc via a flexible neck region. Numerous cortical granules are observed scattered throughout the body and densely packed along the neck. The adoral zone is formed by about 81 external and 24 infundibular paramembranelles. The paroral membrane, formed by a row of long cilia arranged in monokinetids, extends through a groove in the body to the adhesive disc. Two dorsal kinetids are present along the right body margin and around the neck. The adhesive disc (18 m in diameter) lacks cilia in the area above the velum. The velum covers a row of dikinetids bearing long cilia and four dikineties, two or three of which are interrupted on the ventral surface. Nine to twelve macronuclear nodules connected by isthmuses are distributed in the cytoplasm, plus two nodules located in the adhesive disc and between those there is an ovate micronucleus. © 2011 Published by Elsevier GmbH. Keywords: Brazil; Electron microscopy; Epibiosis; Licnophoridia; Spirotrichea Introduction Licnophora Claparède, 1867, is the sole representative of the subclass Licnophoria Corliss, 1957. The genus remained assigned to the heterotrichs (Tuffrau and Puytorac 1994) until further evidence from molecular analyses undertaken by Lynn and Strüder-Kypke (2002) suggested its assignment to the spirotrichs. Indeed, Licnophora species form a macronu- clear replication band (Silva Neto 1994), which is considered ∗ Corresponding author. Fax: +55 21 2562 6363. E-mail address: idsnet@biologia.ufrj.br (I.D. da Silva-Neto). a synapomorphy of the Spirotrichea (Lynn 2008). Most of the species of Licnophora have been found in epibiosis with marine animals of different phyla. Licnophora chattoni was originally described by Villeneuve-Brachon (1939), who isolated specimens from the gill walls of Phallusia mammillata (Cuvier, 1815) (Ascidia). Further observations made by Villeneuve-Brachon (1940) on the divisional morphogenesis of this organism employing the silver-impregnation technique of Chatton and Lwoff (1930). In the year of 2005, we noticed the presence of high den- sities of L. chattoni on the tentacles and hydranths of the 0932-4739/$ – see front matter © 2011 Published by Elsevier GmbH. doi:10.1016/j.ejop.2011.07.004