A new species of Pseudoacanthocephalus (Acanthocephala: Echinorhynchidae) from the guttural toad, Sclerophrys gutturalis (Bufonidae), introduced into Mauritius, with comments on the implications of the introductions of toads and their parasites into the UK

Pseudoacanthocephalus goodmani n. sp. is described from faecal pellets collected from Sclerophrys gutturalis (Power, 1927), the guttural toad. The species is characterized by a suite of characters, including a proboscis armature of 14–18 longitudinal rows of 4–6 hooks with simple roots, lemnisci longer than the proboscis receptacle, equatorial testes, a cluster of elongated cement glands and eggs without polar prolongations of the middle membrane 72.6–85.8 long. The toad had been accidentally translocated from Mauritius to the UK in a tourist's luggage and survived a washing machine cycle. The guttural toad was introduced into Mauritius from South Africa in 1922 and the cane toad, Rhinella marina (Linneaus, 1758), from South America, between 1936 and 1938. It seems most likely, therefore, that P. goodmani was introduced, with the guttural toad, from South Africa. The cane toad is host to the similar species, Pseudoacanthocephalus lutzi, from the Americas, but P. lutzi has not been recorded from places where the cane toad has been introduced elsewhere. Clearly, the guttural toad is a hardy and adaptable species, although it seems unlikely that it could become established in Northern Europe. Nevertheless, any accidental translocation of hosts poses the potential risk of introducing unwanted pathogens into the environment and should be guarded against.

Descriptions of acanthocephalans, Cathayacanthus spinitruncatus (Rhadinorhynchidae) male and Pararhadinorhynchus magnus n. sp. (Diplosentidae), from marine fish of Vietnam, with notes on Heterosentis holospinus (Arhythmacanthidae)

Males of Cathayacanthus spinitruncatus Amin, Heckmann & Ha, 2014 (Rhadinorhynchinae Lühe, 1912) are described for the first time from Leiognathus equulus in Hai Phong and Nha Trang and from pony fish Nuchequula flavaxilla in Quang Ninh in the Pacific waters of Vietnam. The male allotype status is designated. Males of C. spinitruncatus are smaller and have fewer and smaller proboscis hooks and trunk spines than females. The male reproductive structures are in the posterior fifth of the trunk and with 6 club-shaped cement glands gradually merging into 6 independent cement gland ducts. The proboscis receptacle is more than half as long as the trunk and with a cephalic ganglion at its anterior end. In females, the receptacle is only about one fifth the length of the trunk. Specimens described as Cathayacanthus bagarii Moravec & Sey, 1989 were shown to have been wrongly assigned to Cathayacanthus. Pararhadinorhynchus magnus n. sp. (Diplosentidae) is described from Scatophagus argus off Hai Phong in the Gulf of Tonkin. It is the third species of the genus and is readily distinguished from the Australian species by having a considerably larger trunk and male reproductive structures, and more proboscis hooks. X-ray microanalysis (EDAX) of intact and gallium-cut hooks of P. magnus showed high calcium and phosphate mainly in the central core. Specimens of Heterosentis holospinus Amin, Heckmann & Ha, 2011 (Arhythmacanthidae) are also reported from L. equulus off Quang Binh, new host and locality records.

Helminth parasites from Red Sea fishes: Neowardula brayi gen. nov., sp. nov. (Trematoda: Mesometridae Poche, 1926) and Sclerocollum saudii sp. nov. (Acanthocephala: Cavisomidae Meyer, 1932)

Specimens of the fishes Acanthopagrus bifasciatus Forsskål (Sparidae) and Siganus rivulatus Forsskål (Siganidae) were caught in the Red Sea off the coast of Rabigh, Saudi Arabia. Four (25%) and 24 (80%) of these fishes, respectively, were found to harbour intestinal helminths. Acanthopagrus bifasciatus was parasitised by Neowardula brayi gen. nov., sp. nov. (Trematoda: Mesometridae) and S. rivulatus by Sclerocollum saudii sp. nov. (Acanthocephala: Cavisomidae). Neowardula brayi gen. nov. is similar to Wardula Poche, 1926, but clearly differs from it and from the other four genera of the family Mesometridae Poche, 1926 in having a ventral surface anterior to the intestinal bifurcation greatly modified into a well-developed, relatively deep pouch encircling the genital pore and constantly diagonal testes. Sclerocollum saudii sp. nov. is similar to S. rubrimaris Schmidt et Paprena, 1978 (type species), but clearly differs in having a proboscis only armed with 10 rows of hooks, smaller proboscis hooks, lemnisci much longer than proboscis receptacle and much smaller egg size. The developmental stages of this acanthocephalan (cystacanths, juveniles and immature worms) are also described and figured.

Acanthocephalans of Amphibians and Reptiles (Anura and Squamata) from Ecuador, with the description of Pandosentis napoensis n. sp (Neoechinorhynchidae) from Hyla fasciata

In a survey of 3457 amphibians and reptiles, collected in the Napo area of the Oriente region of Ecuador, 27 animals were found to be infected with acanthocephalans. Of 2359 Anura, 17 animals were infected with cystacanth stages of Oligacanthorhynchus spp., one frog with cystacanths of Acanthocephalus and one, Hyla fasciata, with a neoechinorhynchid, Pandosentis napoensis n. sp. Of 1098 Squamata, two colubrid snakes were infected with cystacanths of Oligacanthoryrchus sp., two with cystacanths of Centrorhynchus spp. and one with unidentifiable cystacanths; one lizard, a gekkonid, was infected with cystacanths of Centrorhynchus sp. and one lizard, an iguanid, with an Oligacanthoryhnchus sp. The new species, P. napoensis can be differentiated from its congenor Pandosentis iracundus in having a proboscis formula of 14 rows of 3 hooks as compared with 22 rows of 4 hooks and the lemnisci longer than the proboscis receptacle rather than the same length or shorter. Pandosentis napoensis may represent a host capture from fresh water fishes. Cystacanths of Centrorhynchus and Oligacanthorhynchus have been previously reported from South American amphibians and reptiles. Surprisingly, no adult Acanthocephalus were collected in this survey, although five species are known to occur in South American amphibians and reptiles.

A comparative morphological study of the Stutzzelle (support cell) in the phylum Acanthocephala

The location and structure of the Stutzzelle is reconstructed, using light microscopy, in 12 species representing the three classes of the phylum Acanthocephala, using serial transverse, sagittal, and longitudinal sections of adult worms. A basic pattern with three different variations, one for each class, is described along with family and generic variations in the Eoacanthocephala and Paleacanthocephala. The association of the Stutzzelle with the apical and neck sense organs in those species with these organs is described. Its absence from one species without neck and apical sense organs is discussed. The variable number of nuclei in the Stutzzelle in the three classes is described with the Eoacanthocephala having a binucleate, the Paleacanthocephala, a tri- or bi-nucleate, and the Archiacanthocepala, a pentanucleate Stutzzelle. The apical sense organs in the Archiacanthocephala, especially double apical sense organs in Moniliformis moniliformis, and the absence of apical sense organs in the Eoacanthocephala and Paleacanthocephala are described. The location of the Stutzzelle on the inner surface of the dorsal wall of the proboscis receptacle is described in the Eoacanthocephala and Paleacanthocephala. The location of the Stutzzelle in the Archiacanthocephala is redescribed as dorsal instead of ventral, making the location consistent in the phylum Acanthocephala.