Cyclocoelum mutabile ( Zeder, 1800 )

Dronen, Norman O. & Blend, Charles K., 2015, Updated keys to the genera in the subfamilies of Cyclocoelidae Stossich, 1902, including a reconsideration of species assignments, species keys and the proposal of a new genus in Szidatitreminae Dronen, 2007, Zootaxa 4053 (1), pp. 1-100 : 11-14

Cyclocoelum mutabile ( Zeder, 1800) — Type species

Syn. C. microstomum ( Creplin, 1829) Type host. This host was originally reported as Fulica chloropodis ; however, this species of coot is not currently recognized, and it is most likely that it was the Eurasian coot, Fulica atra Linnaeus (Gruiiformes: Rallidae ).

Type locality. Germany; specific type locality unknown.

Additional hosts. Common moorhen, Gallinula chloropus (Linnaeus) (Gruiiformes: Rallidae ); Gallinula delicata (this species of bird is not currently recognized; it was likely Wilson’s snipe, Gallinago delicata Ord [ Charadriiformes : Scolopacidae ], which is considered to be a subspecies of the common snipe, Gallinago gallinago [Linnaeus] [ Charadriiformes : Scolopacidae ]); common greenshank, Tringa nebularia (Gunnerus) — Bashkirova (1950); species of Anser Brisson , Ardea Linnaeus (Syn. Megalornis Gray ), Bucephala Baird , Gallinago Brisson (Syn. Capella Frezel ), Himantopus Brisson , Jacana Brisson , Limosa Brisson , Melanitta Boie (Syn. Oidemia Fleming), Rallus Linnaeus , Scolopax Linnaeus , Tringa Linnaeus , and Vanellus Brisson—Sinha & Sahay (1975) . NHMUK on-line Host-Parasite Database lists 45 host species for C. mutabile and 12 host species for C. microstomum (avian and invertebrate).

Additional locality. Russian Federation—Yamaguti (1971). NHMUK on-line Host-Parasite Database lists 22 localities and 94 references for C. mutabile and 4 localities and 15 references for C. microstomum .

Previously proposed synonyms. Cyclocoelum (Antepharyngeum) mutabile ( Zeder, 1800) — Witenberg (1923, 1926); Monostomum himantopodis Rudolphi, 1819 , Monostomum microstomum Creplin, 1829 (= Cyclocoelum microstomum [ Creplin, 1829]) and Cephalogonimus ovatus ( Rudolphi, 1803) — Joyeux & Baer (1927); Cyclocoelum problematicum ( Stossich, 1902) (= Selfcoelum problematicum [ Stossich, 1902] n. comb.), Cyclocoelum cuneatum Harrah, 1922 , Cyclocoelum lobatum Khan, 1935 (= Selfcoelum lobatum [ Khan, 1935] n. comb.) and Cyclocoelum leidyi Harrah, 1922 — Bashkirova (1950); Monostomum microstomum (= C. microstomum ), Cephalogonimus ovatus , Cyclocoelum pseudomicrostomum Harrah, 1922 , Cyclocoelum goliath Witenberg, 1923 (= Selfcoelum goliath [ Witenberg, 1923] n. comb.), Cyclocoelum paradoxum Marcó del Pont, 1926 (= Selfcoelum paradoxum [Marcó del Pont, 1926]), Cyclocoelum japonicum Kurisu, 1932 , Cyclocoelum microcotyleum Noble, 1933 and Cyclocoelum lahillei Dollfus, 1948 (= Selfcoelum lahillei [ Dollfus, 1948])— Dubois (1959).

Host Fulica americana Fulica atra Fulica atra Aythya fuligula Rallidae Rallidae Rallidae Anatidae

Locality North America Germany Germany Europe

NP = Not present. 1Estimated from figure in original description. 2Measurements from Kossack (1911). 3Estimated from Fig. 2 of Kossack (1911). 4Estimated from Fig. 1 of Kossack (1911). 5Measurement from Yamaguti (1971).

Estimated from figure in original description; 2Measurements from original material made by Dubois (1959).

Remarks. The original description of Monostomum mutabile Zeder, 1800 by Zeder (1800) and the description of Monostoma mutabile by Rudolphi (1809) were minimal and incomplete. Stossich (1902) provided some additional information concerning the species, but he apparently followed Braun (1901) by considering the pharynx to be the oral sucker (“ventosa”) in cyclocoelids, referring to a “sucker” at the anterior end in descriptions and labeling the pharynx as “Ve” (= ventosa) in figures of species. Note that unlike Figs. 123, 124 and 126 of Bashkirova (1950), Fig. 125 appears to indicate the presence of a rudimentary oral sucker. It is possible that Fig. 125 represents a different species. Harrah (1922) considered C. mutabile Zeder, 1800 to have a rudimentary oral sucker; however, Kossack (1911) provided a description and illustration ( Fig.1 ) of what he considered to be C. mutabile based on specimens found in the Konigsberg and Garcia Collections, which generally have been accepted as representing this species (e.g. Yamaguti 1971), and where there is not a rudimentary oral sucker. Cyclocoelum microstomum ( Creplin, 1829) was originally described as Monostomum microstomum mihi Creplin, 1829 , but Figs. 10 and 11 do not show details of the internal structures. Creplin (1829) apparently based the original determination of this species on two different species (see Kossack 1911). Kossack (1911) distinguished C. microstomum from Hyptiasmus ominosus Kossack, 1911 (the second species in Creplin’s material; = A. ominosus [ Kossack, 1911]), and redescribed and illustrated C. microstomum . Although Fig. 11 of Creplin (1829) appears to show the presence of a region that might be interpreted as a rudimentary oral sucker, Kossack (1911) did not find this feature in the material he used for the redescription of C. microstomum . Cyclocoelum microstomum cannot be distinguished from C. mutabile and we support its synonymy with it as proposed by Joyeux & Baer (1927) and Dubois (1959). In addition to the similarities in measurements, both have a largely intercecal uterus, the posterior-most uterine loops do not invade the posttesticular space and they are both from F. atra from Germany.

Figures

FIGURES 1 – 4. Diagrammatic representations of species representing the genera assigned to Cyclocoelinae Stossich, 1902. 1. Cyclocoelum Brandes, 1892 represented by Cyclocoelum mutabile (Zeder, 1800), adapted from Kossack (1911); 2. Selfcoelum Dronen, Gardner, & Jiménez, 2006 represented by Selfcoelum limnodromi Dronen, Gardner, & Jiménez, 2006, adapted from Dronen et al. (2006 a); 3. Psophiatrema Dronen & Kinsella, 2009 represented by Psophiatrema greineri Dronen & Kinsella, 2009, adapted from Dronen & Kinsella (2009); 4. Circumvitellatrema Dronen, Greiner, Ialeggio & Nolan, 2009 represented by Circumvitellatrema momota Dronen, Greiner, Ialeggio & Nolan, 2009, adapted from Dronen et al. (2009). Abbreviations: C, cecum; G, genital pore; O, ovary; P, pharynx; S, rudimentary oral sucker; T, testis; U, uterus; V, vitelline field.

FIGURES 10 – 13. Diagrammatic representations of species representing the genera assigned to Hyptiasminae Dollfus, 1948. 10. Hyptiasmus Kossack, 1911 represented by Hyptiasmus arcuatus (Brandes, 1892 of Stossich, 1902), adapted from Kossack (1911); 11. Prohyptiasmus Witenberg, 1923 represented by Prohyptiasmus magnus (Johnston, 1917), adapted from Johnston (1917); 12. Allopyge Johnston, 1913 represented by Allopyge antigones Johnston, 1913, adapted from Johnston (1913); 13. Morishitium Witenberg, 1928 represented by Morishitium texanense Dronen, 2007, adapted from Dronen (2007 a). Abbreviations: C, cecum; G, genital pore; O, ovary; P, pharynx; S, rudimentary oral sucker; T, testis; U, uterus; V, vitelline field.