Plectanocotyle jeanloujustinei, Cappelletti & Bouguerche, 2024

Cappelletti, Alice & Bouguerche, Chahinez, 2024, “ Something old, something new, something borrowed, and the oioxeny is true ”: description of Plectanocotyle jeanloujustinei n. sp. (Polyopisthocotylea, Plectanocotylidae) from the MNHN Helminthology collection with novel molecular and morphological data for P. gurnardi (Van Beneden & Hesse, 1863) (sensu stricto) from Sweden, International Journal for Parasitology: Parasites and Wildlife 23, pp. 100914-100914 : 100914-

3.2.2. Plectanocotyle jeanloujustinei n. sp. ( Figs. 9–11 )

Synonym: Plectanocotyle cf. gurnardi of Ayadi et al. (2022).

Type-host: Chelidonichthys lastoviza ( Perciformes : Triglidae ), the streaked gurnard.

Type-locality: off Bouharoun (36 37′24.17″N, 2 39′17.38″E), Algerian coast, Western Mediterranean .

Site on host: Gills.

Type-specimens: Holotype (MNHN HEL1721 ), 11 paratypes on slides (MNHN HEL1711–1720, MNHN HEL1722 ) previously deposited in the collections of the Mus´eum National d’ Histoire Naturelle, Paris, and 8 slides (see below) (MNHN HEL1727– HEL1734 ) including six with sequences (MNHN HEL1729– HEL1734 ).

Paratype of specimens with molecular information (hologenophores): specimens from Chelidonichthys lastoviza off Algeria, Western Mediterranean : specimens lacking only the haptor MNHN HEL1729 , GenBank MW796586 ; MNHN HEL1730 , GenBank MW796587 ; MNHN HEL1732 , GenBank MW796589 ; MNHN HEL1733 , GenBank MW796590 ; MNHN HEL1734 , GenBank MW796591 . Specimen lacking a lateral posterior part, MNHN HEL1731 , GenBank MW796588 . Specimens with only the anterior end of the body including the male copulatory organ MNHN HEL1727, MNHN HEL17287 . The missing parts were excised and used for DNA extraction.

ZooBank registration: To comply with the regulations set out in article 8.5 of the amended 2012 version of the International Code of Zoological Nomenclature (ICZN), details of the new species have been submitted to ZooBank. The Life Science Identifier (LSID) for the new name Plectanocotyle jeanloujustinei is urn:lsid:zoobank.org:act:E3D55AC5-D999-4EDE-984C-BE518126D8C9 .

Etymology: The specific epithet “ jeanloujustinei ” honors French parasitologist Jean-Lou Justine, Professor and curator at the Mus´eum National d’ Histoire Naturelle, Paris, France for his extensive efforts in studying the systematics and biodiversity of polyopisthocotyleans in the western Mediterranean.

3.2.2.1. Description. Measurements in Table 5. Body stocky, elongated. ( Fig. 9 A ). Haptor symmetrical, faintly delineated from body proper, with three pairs of clamps. Clamps pedunculated ( Fig. 6 B ), arranged in two rows. Clamps consisting of two opposable jaws ( Fig. 9 B, C ), anterior jaw ( Fig. 10 A ) and posterior jaw ( Fig. 10 B ). Organisation of clamps sclerites and muscles similar to that of P. gurnardi sensu stricto ( Fig. 10 C ).

Anchor-bearing terminal lappet present ( Fig. 9 D ), linguiform, consisting of a thick short outgrowth. Terminal lappet with three pairs of anchors: two pairs of hamuli and one pair of uncinuli. Lateral hamuli longer than median hamuli. Uncinuli small, located between hamuli.

Mouth subterminal, elongated transversally. Two oval prohaptoral suckers. Pharynx voluminous, pyriform. Intestine with numerous lateral and medial diverticula. Intestinal bifurcation anterior to MCO. Caeca probably not confluent. Testes post-ovarian, intercaecal, mainly in posterior half of body proper, oval, 14–35 in number. Vas deferens sinuous, extending along body midline to male copulatory organ. Vas deferens expanded anteriorly to a globular pyriform seminal vesicle. In its anterior region, vas deferens ending in a narrow thin-walled duct. Cirrus consisting of a sheaf of long slender spines.

Peripheral spines tightly packed. Most inner spines (median) shorter. Median spines delineating a thin canal, receiving the vas deferens.

Male accessory glands paired, with two related smaller reservoirs, located at level of cirrus on each side of the body ( Fig. 6 C ). Male accessory glands with several prostatic glands. Secretions of prostatic glands collecting in small reservoirs. Each reservoir continued rearward by a short duct. Ducts emerging from reservoirs joined medially, forming a prostatic canal. Prostatic canal entering the bundle of spines and uniting with vas deferens.

Ovary pre-testicular, ( Fig. 8 ). Proximal overlapping most anterior testis. Distal end curved. Oviduct arising from distal end of ovary and connecting common vitelline duct reservoir and ootype ¨. Mehlis’ glands at base of o¨otype. Uterus originating from ootype ¨and extending anteriorly to genital atrium. Vitellarium follicular, well developed, co-extensive with caeca, extending from level of mal copulatory organ to posterior extremity of body and extending into haptor. Transverse vitelline ducts Y-shaped; dorsal transverse vitelloducts fused approximately at o¨otype level; common vitelline duct median, fairly long. Eggs fusiform with a single polar filament. Polar filament coiled.

Figures

Fig. 9. Plectanocotyle jeanloujustinei n. sp. ex Chelidonichthys lastoviza from the western Mediterranean. A, Body, holotype, ventral view (HEL 1721). B, Clamp, hologenophore, ventral view (HEL 1731). C, Clamp, paratype, dorsal view (HEL 1717). D, terminal lappet, paratype (HEL 1717). E, Anterior end showing male copulatory organ, paratype, ventral view (HEL 1720). F, Egg, paratype (HEL 1714).

Fig. 10. Plectanocotyle jeanloujustinei n. sp. ex Chelidonichthys lastoviza from the western Mediterranean. Disposition of clamps sclerites. A, Dorsal jaw. B, Ventral jaw. C, Clamp, dorsal view (HEL 1713).

Fig. 11. Plectanocotyle jeanloujustinei n. sp. ex Chelidonichthys lastoviza from the western Mediterranean. Detail of the reproductive organs in the region of ovary, ventral view (HEL 1715).

Fig. 6. Plectanocotyle gurnardi (Van Beneden and Hesse, 1863) sensu stricto ex Eutrigla gurnardus from the North Sea, Sweden. A, Body, ventral view (SMNH 216639). B, Clamp, ventral view (SMNH 216593). C, Anterior end showing male copulatory organ, ventral view (SMNH 216586). D, Egg, (SMNH 216594).

Fig. 8. Plectanocotyle gurnardi (Van Beneden and Hesse, 1863) sensu stricto ex Eutrigla gurnardus from the North Sea, Sweden, Detail of the reproductive organs in the region of ovary, ventral view (SMNH 216584).