taxonID	type	description	language	source
03A65F6AFFACA85575FCFFE5557CFD77.taxon	diagnosis	Diagnosis Marine, brackish or freshwater loricate peritrichs, usually with one or two zooids per lorica. Lorica borne on a stalk and attached to aquatic animals, plants or inanimate objects. Lorica without valves or other means of closing the aperture. Inner layer or septum sometimes present enclosing a space at the posterior end of the lorica; septum connected to the base of the lorica via a mesostyle. Zooid (s) attached to the base of the lorica (or septum) directly or via an endostyle (Warren & Paynter, 1991).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFACA85475F6FDD852E6F89D.taxon	description	(FIGS 2 – 4) Material examined Light-microscopy measurements based on six Cothurnia specimens found on the polychaete Malmgrenia lilianae, north Adriatic Sea, station SJ 107, 21 June 2005. Additional material examined from the polychaete M. lilianae, north Adriatic Sea: station SJ 005, 30 August 2005 (three polychaetes), 18 October 2006 (one polychaete); station SJ 007, 15 March 2005 (one polychaete; mounted for SEM), 21 June 2005 (two polychaetes), 18 October 2006 (one polychaete), 13 September 2007 (one polychaete); station SJ 107, 21 June 2005 (one polychaete; mounted for SEM), 22 December 2005 (two polychaetes), 13 September 2007 (two polychaetes, one mounted for SEM), 12 October 2007 (one polychaete). Additional material examined from the polychaete M. andreapolis, north Adriatic Sea: station SJ 005, 22 September 2006 (one polychaete, mounted for SEM); station SJ 107, 12 October 2007 (one polychaete). Description Lorica conical, smooth, with thin wall, 57 – 77 μm long (53 – 56 μm after Warren & Paynter, 1991) × 35 μm wide. Aperture circular 30 – 33 μm (35 – 37 μm after Warren & Paynter, 1991) in diameter, the edge of aperture with extremely small, irregular outgrows (Figs 2 C, 4 C). External stalk conical, flexed near substrate (Fig. 4 A), with an annular bulge in connection with lorica base and basal disc, 18 – 35 μm (54 – 57 μm after Warren & Paynter, 1991) long, with conspicuous transverse folds (Fig. 4 D). Endostyle short, broad, with longitudinal striae that are nor visible in some cases. Mesostyle absent. Generally, two zooids are present (Figs 2 D, 4 B). Zooid conical, 85 × 40 μm, and extends between one third and one half of its length beyond aperture (Fig. 4 B). The length of contracted zooids 31 – 59 μm, width 7 – 21 μm. Peristomial lip well-developed, 45 μm in diameter. Disc convex. Contractile vacuole lies just below peristome. Macronucleus elongate slightly curved anteriorly. Pellicular striations conspicuous. Remarks New specimens differ from the original description of C. amphicteis by the presence of two zooids in the lorica (with one exception) and the greater length of the lorica. Only contracted zooids were measured. The diagnosis of related species C. acuta Levander, 1915 (after Warren & Paynter, 1991) is rather similar to C. amphicteis. In both diagnoses, the absence of a mesostyle was mentioned. However, on Precht’s (1935) picture, C. acuta has the typical mesostyle with longitudinal striae. In our specimens, the mesostyle was absent, thus we consider them C. amphicteis. The suggested synonymy between C. acuta and C. amphicteis needs further consideration. This is the first finding of the species after its original description by Lang (1948). Habitat Marine, originally found attached to the chaetae of polychaete Amphicteis gunneri (M. Sars, 1835) (fam. Ampharetidae) (type host) in coastal waters of Sweden, Baltic Sea (type locality) (Lang, 1948). Other locality: north Adriatic Sea, on the chaetae of polychaetes Malmgrenia lilianae and M. andreapolis (this paper).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFABA8517691FA8853BCF949.taxon	description	FIGS 5 – 6 Material examined Material examined by light microscopy (measurements based on six C. peloscolicis specimens) and SEM microscopy from one specimen of polychaete Sthenelais boa, north Adriatic Sea, station SJ 007, 5 March 2004. Description Lorica extended near the base and slightly converged toward aperture, smooth, not compressed, 61 – 86 μm (81 μm after Warren & Paynter, 1991) × 26 – 32 μm (27 – 41 μm after Warren & Paynter, 1991) (Figs 5 B, 6 C). Aperture circular when viewed from above, 23 – 32 μm in diameter (15 × 33 μm after Warren & Paynter, 1991), the edge of aperture without any outgrow (Fig. 6 B). External stalk short, cylindrical, without folds, 10 – 16 μm long (20 μm after Warren & Paynter, 1991); mesostyle and endostyle absent (Fig. 5 B). Stalk with longitudinal striae in some cases. Generally, two zooids present (Fig. 5 B). Zooid 80 × 18 – 22 μm, extending just beyond aperture. The length of contracted zooid 26 – 55 μm, width 11 – 18 μm. Peristomial lip 27 μm in diameter. Contractile vacuole small and situated in the peristomal region. Macronucleus straight, 50 μm long. Pellicular striations inconspicuous. Remarks This is the first finding of the species after its original description by Precht (1935). Habitat Marine, originally found as epibiont of the oligochaete Tubificoides benedii (d’Udekem, 1855) [reported as Peloscolex benedeni (d’Udekem, 1855); type host] from the Bay of Kiel, Germany (Baltic Sea) (type locality) (Precht, 1935). Other locality: north Adriatic Sea on the chaetae of polychaete Sthenelais boa (this paper). A REVIEW OF THE PERITRICH CILIATE EPIBIONTS ON POLYCHAETES SUBCLASS PERITRICHIA STEIN, 1859	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA8A85F751CF9EE5033FC27.taxon	description	Syllis sp. 1 (Fam. Syllidae) – on the intersegmental furrows, close to parapodial bases; Las Cruces, Central Chile, south-eastern Pacific Ocean (Alvarez-Campos et al., 2014). Syllis sp. 2 (Fam. Syllidae) – on the intersegmental furrows, close to parapodial bases and on the prostomium; Las Cruces, Central Chile, south-eastern Pacific Ocean (Alvarez-Campos et al., 2014). Salvatoria concinna (Westheide, 1974) (Fam. Syllidae) – on the intersegmental furrows, close to parapodial bases; Las Cruces, Central Chile, south-eastern Pacific Ocean (Alvarez-Campos et al., 2014). Salvatoria sp. (Fam. Syllidae) – on the intersegmental furrows, close to parapodial bases; Las Cruces, Central Chile, south-eastern Pacific Ocean (Alvarez-Campos et al., 2014).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA6A85F7537FBA65591F97B.taxon	description	PARAVORTICELLA TEREBELLAE (FAURÉ-FREMIET, 1920) Terebella lapidaria Linnaeus, 1767 (Fam. Terebellidae) – forming fluffy spots on the polychaete skin; Germany (Kahl, 1935). Terebellides stroemii Sars, 1835 (Fam. Trichobranchidae) – on the ventral body side, from the anterior part under gills to the mid body; Bay of Kiel, Germany, Baltic Sea (Precht, 1935).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA7A85E7778FBCA530FF9F6.taxon	description	Malmgrenia andreapolis McIntosh, 1874 (Fam. Polynoidae) – on the chaetae; this research, north Adriatic Sea, Mediterranean Sea. Malmgrenia lilianae (Pettibone, 1993) (Fam. Polynoidae) – on the chaetae; this research, north Adriatic Sea, Mediterranean Sea.	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA7A85E75F2FD765438FC83.taxon	discussion	Remark: Dons (1946) described this species as Cothurnia trophoniae Dons, 1946, although Dons (1918) previously described the same species as C. pedunculata (Warren & Paynter, 1991).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA4A85D76B9FEE15309FD2A.taxon	description	Spirorbis (Spirorbis) spirorbis (Linnaeus, 1758) (Fam. Serpulidae) – on the tube; Bay of Kiel, Germany, Baltic Sea (Precht, 1935).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA4A85D7556FD3152E4FB11.taxon	description	Nephtys sp. (Fam. Nephtyidae) – Bay of Kiel, Germany, Baltic Sea (Precht, 1935, as Cyclochaeta serpularum). Phyllodoce laminosa Savigny in Lamarck, 1818 (Fam. Phyllodocidae) – Bay of Kiel, Germany, Baltic Sea (Precht, 1935, as C. serpularum). Serpula sp. (Fam. Serpulidae) – branchiae; Germany (Kahl, 1935, as Cyclochaeta (Leiotrocba) serpularum). Remark: Urceolaria serpularum was originally described in the monotypic genus Leiotrocha Fabre-Domergue, 1888. Haider (1964) transferred Leiotrocha serpularum into the genus Urceolaria, which was accepted by Xu & Song (2003), but not by Lynn (2008), who insisted on validity of the monotypic family Leiotrochidae Johnston, 1938. Recent morphological and genetic analyses by Zhan et al. (2013) support that Leiotricha should be placed in Urceolaria.	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA4A85D76E3FB495047FAE6.taxon	description	Spirorbis (Spirorbis) spirorbis (Linnaeus, 1758) (Fam. Serpulidae) – on the tube; Bay of Kiel, Germany, Baltic Sea (Precht, 1935).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA4A85D76ABFA495047F93B.taxon	description	Nephtys sp. (Fam. Nephtyidae) – Bay of Kiel, Germany, Baltic Sea (Precht, 1935). Nereimyra punctata (Müller, 1788) (Fam. Phyllodocidae) – on the whole body, including the long cirri; Bay of Kiel, Germany, Baltic Sea (Precht, 1935). Eteone longa (Fabricius, 1780) (Fam. Phyllodocidae) – on all parts of the body; Bay of Kiel, Germany, Baltic Sea (Precht, 1935).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
03A65F6AFFA5A85C7695FFDA51C7FA64.taxon	description	UNCLASSIFIED PERITRICHOUS CILIATES Polydora neocaeca Wiliams & Radaskevsky, 1999 (Fam. Spionidae) – on the hoods of the bidentate hooded hooks; State of Rhode Island, North America, north-western Atlantic Ocean (Wiliams & Radaskevsky, 1999). Ampharete santillani Parapar, Kongsrud, Kongshavn, Alvestad, Aneiros & Moreira, 2017 (Fam. Ampharetidae) – on the abdominal uncini, the branchial surface, the dorsolateral area behind the branchial surface and the ciliated buttons over the abdominal neuropodia; Galicia, north-western Spain and off Morocco, north-eastern Atlantic Ocean (Parapar et al., 2018). ANALYSES OF THE POLYCHAETE – PERITRICH CILIATE ASSOCIATION Forty taxa (30 determined to species level) of peritrich ciliates belonging to 12 genera and seven families are up to date recorded as epibionts of polychaetes. Most of them belong to the order Sessilida, while only five taxa belong to the order Mobilida. The most diverse are representatives of the genus Cothurnia (11 taxa, of which ten determined to species level). Forty-eight polychaete taxa (39 determined up to species level) are known as hosts for peritrich ciliate epibionts. They belong to the families Ampharetidae, Arenicolidae, Capitellidae, Flabelligeridae, Nephtyidae, Nereididae, Nerillidae, Onuphidae, Orbiniidae, Pectinariidae, Phyllodocidae, Polynoidae, Serpulidae, Sigalionidae, Spionidae, Syllidae, Terebellidae and Trichobranchidae. Most polychaete basibionts pertain to the family Syllidae (11 taxa, of which eight determined to species level).	en	Semprucci, Barbara Mikac Federica, Guidi, Loretta, Ponti, Massimo, Abbiati, Marco, Balsamo, Maria, Dovgal, Igor (2020): Newly discovered associations between peritrich ciliates (Ciliophora: Peritrichia) and scale polychaetes (Annelida: Polynoidae and Sigalionidae) with a review of polychaete-peritrich epibiosis. Zoological Journal of the Linnean Society 188: 939-953
