Entobdella soleae (Van Beneden & Hesse, 1863)

Kearn, Graham C., Whittington, Ian D. & Evans-Gowing, Richard, 2007, A revision of Entobdella Blainville in Lamarck, 1818, with special emphasis on the nominal (type) species “ Entobdella hippoglossi (Müller, 1776) Blainville, 1818 ” (Monogenea: Capsalidae: Entobdellinae) from teleost flatfishes, with descriptions of three new species and a new genus, Zootaxa 1659, pp. 1-54 : 46

Entobdella soleae ( Van Beneden & Hesse, 1864) Johnston, 1929

( Figs. 15J, 27–31, 37)

[syn. Phyllonella soleae Van Beneden & Hesse, 1864 ; Tristoma soleae ( Van Beneden & Hesse, 1864) Taschenberg, 1878; Epibdella soleae ( Van Beneden & Hesse, 1864) Monticelli, 1890; Epibdella (Phylline) soleae ( Van Beneden & Hesse, 1864) Monticelli, 1902; Epibdella producta Linstow, 1903 ; Phylline soleae ( Van Beneden & Hesse, 1864) Linstow, 1903; Phyllonella producta (Linstow, 1903) MacCallum, 1927 ; Phyllonnella soleae (Van Beneden & Hesse, 1863) Froissant, 1930; Entobdella (Entobdella) soleae ( Van Beneden & Hesse, 1864) Johnston, 1929; Entobdella producta (Linstow, 1903) Meserve, 1938 .]

Type host and locality: Common or Dover sole, Solea solea (Linnaeus, 1758) ( Pleuronectiformes : Soleidae ); locality not stated by Van Beneden & Hesse (1864) but presumably the North Sea or English Channel.

Other localities on S. solea: Lawler (1981 , table 76) lists other localities off the Atlantic coast of Europe. S. solea occurs in the Mediterranean Sea but E. soleae has not been reported on it (see Kearn 2002).

Other hosts and localities: Sand sole, Pegusa lascaris (Risso, 1810) ( Pleuronectiformes : Soleidae ), Roscoff ( Sproston 1946); Senegalese sole, Solea senegalensis Kaup, 1858 ( Pleuronectiformes : Soleidae ), Atlantic Ocean off Portugal ( Carvalho-Varela & Cunha-Ferreira 1987); Spotted ray, Raja montagui Fowler, 1910 ( Rajiformes : Rajidae ), Plymouth, U.K. ( Kearn 1967b; it is likely that the parasites transferred to the skin of R. montagui from S. solea in a tightly packed trawl net).

Site on host: Skin. Adult parasites usually on the lower surface ( Kearn 1988).

Voucher specimens: 5 adult specimens ( BMNH Nos. 2007.4.26.18-22, 5 slides). Five adult specimens ( SAMA AHC No. 29198, 5 slides) .

Specimens studied: 10 adult voucher specimens from Solea solea as listed above (see Table 2).

Redescription ( Fig. 37): The anatomy and biology of E. soleae have been studied more intensively than in any other species of the genus. For general accounts, see Kearn (1998, 2004) and for details of the reproductive system see Kearn (1970, 1985, 1993). The following additional observations were made in the present study. Total length 5089 (4061 – 6166) (n = 10); body width 2589 (2256 – 2948) (n = 10); haptor length and breadth 1152 (1025 – 1443) and 1263 (950 – 2587) respectively (n = 10); accessory sclerite length 218 (186 – 260) (n = 20); anterior hamulus length 567 (502 – 744) (n = 20); posterior hamulus length 137 (122 – 155) (n = 15); pharynx length and breadth 531 (409 – 643) and 666 (533 – 850) respectively (n = 8); testis length and breadth 430 (325 – 511) and 531 (388 – 650) respectively (n = 20). Vagina comprising distal straight, narrow entrance tube ( Figs. 28, 29, 37A), 3 – 8 in diameter (in resin sections), communicating proximally and abruptly with coiled region usually containing sperm ( Fig. 30). Terminal (distal) region of vagina adjacent to ventral opening not specialised as it is in “ Entobdella hippoglossi ”. Proximal coils spacious, forming an entangled knot ( Figs. 31, 37A), contrasting with main vagina of “ E. hippoglossi ” in which coils less voluminous and arranged in tight, narrow column. Ventral surface of haptor papillate (refer to Lyons 1973); papillae widespread over whole ventral surface of haptor ( Fig. 37A).

Differential diagnosis: Readily distinguished from all other members of the genus by strongly curved (hook-like) accessory sclerites ( Figs. 15J, 37B). On skin of soleid flatfishes, including common sole ( Solea solea ).

Comments. This is the best known and most easily recognised species of Entobdella , but a type series is not known to exist. This prompted us to deposit 10 voucher specimens in museums (see above).