Two new species of Caulobothrium (Cestoda: “Tetraphyllidea”) from the duckbill eagle ray, Aetomylaeus bovinus (Myliobatiformes: Myliobatidae), off Senegal with new insights on morphological features of the genus

Two new species of the cestode genus Caulobothrium, collected from the duckbill eagle ray, Aetomylaeus bovinus, off Senegal, are described. Although postulated as sister taxa in an earlier molecular phylogenetic analysis, Caulobothrium multispelaeum n. sp. and Caulobothrium katzi n. sp., respectively, are among the smallest and largest members of the genus. The smaller species is unique among its congeners in possessing unusual medial longitudinal grooves along the dorsal and ventral surfaces of its strobila that develop into a tandem series of elliptical apertures on the posterior proglottids. The inner surfaces of these apertures stained positively with McManus’ periodic acid Schiff in a manner similar to that seen in members of the distantly related lecanicephalidean genus Elicilacunosus. The larger species differs from its congeners in size, number of proglottids, and arrangement of bothridial loculi. Both new species were found to possess a small apical sucker on the anterior margin of each of their bothridia. Scanning electron microscopy (SEM) and frontal sections of a bothridium of Caulobothrium tetrascaphium suggests that this species also bears an apical sucker. Examination of the hologenophore of the species provisionally referred to as Caulobothrium n. sp. 5 in the earlier molecular analysis indicates it is conspecific with the recently described Caulobothrium pedunculatum, which was also determined to possess bothridial apical suckers. This leads us to suspect that this feature may be found to occur in all members of the genus. SEM of specimens of Caulobothrium for the first time indicates their bothridial surfaces are covered with filitriches of various sizes but lack spinitriches; spinitriches were seen only on the cephalic peduncle of C. katzi n. sp. The geographic distribution and host associations of Caulobothrium are expanded to include data now available for all species. The diagnosis of the genus is revised to include all of this information.

A new genus and three new species of Anthocephaliidae (Cestoda, Rhinebothriidea) from the round fantail stingray,Taeniurops grabata(Chondrichthyes, Dasyatidae) from the Mediterranean Sea and Atlantic Ocean

The spiral intestines of a total of 16 round fantail stingraysTaeniurops grabatafrom the Mediterranean Sea off Tunisia were examined for cestodes. A new genus is erected in the Anthocephaliidae (Rhinebothridea) asAlveobothriumgen. n., withAlveobothrium grabatumsp. n. as its type species; the new genus differs from the other genera in the order in that its members possess bothridia with an apical sucker, marginal loculi and multiple staggered rows of facial loculi.Alveobothrium zarzisensesp. n. is also described. The species differ in the number of marginal loculi and in proglotid anatomy. Another anthocephaliid belonging to the genusAnthocephalumis also described fromT. grabata. Anthocephalum jeancadenatisp. n. is most similar toA. alicaeandA. michaeli, but differs in size of terminal proglottid and number of proglottids. All these new species are also found in formalin-preserved cestodes fromT. grabatacollected at Gorée Island (Senegal) between 1946 and 1954 by the French ichthyologist J. Cadenat and conserved in the personal collection of the late L. Euzet. The presence of the same rhinebothriideans species parasitizingT. grabatain both the Mediterranean (Tunisia) and the eastern Atlantic (Senegal) is discussed.

Cairaeanthus gen. n. (Cestoda, Rhinebothriidea), with the Description of Two New Species from Dasyatis pastinaca in the Black Sea and the Sea of Azov

Cairaeanthusgen. n. (Cestoda, Rhinebothriidea), with the Description of Two New Species fromDasyatis pastinacain the Black Sea and the Sea of AzovTwo new species were identified among cestodes collected fromDasyatis pastinaca(Linnaeus, 1758) in the Black Sea and the Sea of Azov. Their morphology corresponds in the most characters to the descriptions ofPhyllobothrium lactucavan Beneden, 1850 andP. gracilisWedl, 1855 by L. Borcea (Borcea, 1934) and T. P. Pogorel'tseva (Pogorel'tseva, 1960) from the same host and seas. However, some morphological characters of these cestodes (namely, the marginal loculi on the pedicellate bothridia, cephalic peduncle, absence of the apical sucker and post-poral testes, genital pore opening marginally, close to posterior end of proglottid) correspond to diagnosis of Rhinebothriidea. Since the species from the Black Sea and the Sea of Azov did not fit diagnoses of any known genera currently belonging to Rhinebothriidea, the new genus,CairaeanthusKornyushin et Polyakova, gen. n., with two species,C. ruhnkeiKornyushin et Polyakova, sp. n. andC. healyaeKornyushin et Polyakova, sp. n., is established.Cairaeanthusgen. n. differs fromAnthocephalumLinton, 1890 in absence of apical sucker, posteriorly bifid bothridia and vitelline fields interrupted by the ovary, not extending in the posterior end of the proglottid. The new genus can be distinguished fromRhinebothriumLinton, 1890,Echeneibothiumvan Beneden, 1850,RhabdotobothriumEuzet, 1953,RhinebothroidesMayes, Brooks et Thorson, 1981,ScalithriumBall, Neifar et Euzet, 2003 by the absence of facial loculi on the bothridia and by numerous vitelline follicles, stopping at the anterior margin of the ovary; fromRhodobothriumLinton, 1889 - by absence of post-poral testes, and fromSpongiobothriumLinton, 1889 - by numerous vitelline follicles, stopping at the level of ovary.C. ruhnkeisp. n. differs fromC. healyaesp. n. in the lengths of the strobila, the cephalic peduncle and the bothridia pedicel, in size of marginal loculi and the ovary, in the number of the proglottids and the testes in the proglottid, and in the structure of genital atrium. Two new species are differentiated also from the morphologically related speciesPhyllobothrium pastinacaeMokhtar-Mocamouri, Zamali, 1981. Examined type specimens ofP. pastinacaewere attributed to Rhinebothiidea based on a set of morphological characters. However, they appear to differ from all known Rhinebothriidea, including the species from the generaAnthocephalumLinton, 1890 andCairaeanthusgen. n. Taxonomic position ofP.pastinacaeneeds further identification.

Genetic and morphological variability in cestodes of the genus Proteocephalus: geographical variation in Proteocephalus percae populations

Genetic and morphological variability was studied in the tapeworm Proteocephalus percae (Müller, 1780) (Cestoda: Proteocephalidae), a parasite of perch (Perca fluviatilis L.). Geographic variation in isoenzyme patterns, random amplified polymorphic DNA (RAPD) profiles, and morphological characters were found within six natural populations of P. percae from Slovakia and Switzerland. All approaches used showed that similarity was substantially higher among Swiss populations than among Slovak populations. Proteocephalus percae specimens from the Dobšiná water reservoir (Slovakia) differed significantly from all other population sample sets in that they exclusively expressed the genotype Acp92/Acp92 and possessed a specific RAPD profile after amplification with the primer p78 and distinct measurements of the scolex (scolex width and apical sucker). The unique position of the P. percae population from Dobšiná could be related to the contamination of this locality with heavy metals (cadmium), through the possible impact of these metals on the alterations observed. The taxonomic relevance and stability of the morphological characters related to the scolex in the Proteocephalus tapeworm group is confirmed.

A comparison of scolex morphology between the plerocercoid and the adult of Calliobothrium verticillatum (Tetraphyllidea: Onchobothriidae)

The morphological changes associated with the ontogenetic transformation of the scolex from larva to adult were investigated in the tapeworm Calliobothrium verticillatum (Rudolphi, 1819) van Beneden, 1850 by comparing the morphology of plerocercoids collected from the hermit crab Pagurus pollicaris Say, 1817 with that of adult worms collected from the shark Mustelus canis (Mitchell, 1815), using scanning electron microscopy. The apex of the scolex in young plerocercoids bore a conspicuous sucker. Each bothridium was flat and divided into four regions: an anterior oval region with two marginal bumps, and three posterior loculi clearly marked by two costae. The microthrix pattern was not determined for very young plerocercoids. The most conspicuous feature of older plerocercoids was the sucker on the apex of the scolex. The bothridia were concave, and each bore an apical region subdivided into three shallow suckers and three conspicuous loculi. Densely packed blade-like microtriches intermingled with filiform microtriches were visible on all surfaces of the scolex except the surface directly adjacent to the opening of the apical sucker of the scolex, which was entirely devoid of microtriches, and the proximal surfaces of the bothridia, which had only blade-like microtriches. The apical sucker was absent from the scolex adult specimens. The only remnant of this structure was a small knob on the apex of the scolex. The bothridia were concave and bore, from anterior to posterior, three conspicuous apical suckers arranged in a horizontal row adjacent to one another, two pairs of single-pronged hooks, and three conspicuous loculi. Densely packed blade-like microtriches were present on all proximal surfaces of the scolex. Microtriches were not present on the distal surfaces of the apical suckers of the bothridia, on the hooks, or on the distal surfaces of the loculi of the bothridia. The latter regions were covered with very small, round structures. The differences in the microthrix components of the various surfaces of the scolex between the plerocercoid and the adult suggest that complex surface changes occur during this phase of ontogeny. Comparison of the development of this species with that of other onchobothriids suggests that, in general, the number of loculi to be expected in the plerocercoid of an onchobothriid is one plus the number of posthook loculi in the adult.