A new species of Aplectana Railliet & Henry (Nematoda: Cosmocercidae) in Amphisbaena alba Linnaeus (Squamata: Amphisbaenidae) from Minas Gerais State, Brazil

In the present study, we described and illustrated Aplectana minaensis n. sp. (Ascaridida: Cosmocercidae) from the intestinal caecum of Amphisbaena alba Linnaeus (Squamata: Amphisbaenidae). Aplectana minaensis n. sp. is the 5th species described in Brazilian hosts and 58th species assigned to the genus. This species differs from its congeners by a set of unique characters in males: the presence of one unpaired precloacal papilla and gubernaculum, the papillae pattern (4+1:2:6) and total number (12+1), and the size of spicules (400–605 µm). Among the Aplectana species with an unpaired precloacal papilla and gubernaculum, only A. minaensis n. sp. and A. nebulosa Gomez, González & Sanabria, has less than 20 pairs of caudal papillae. However, these species differ in the number of caudal papillae in males (12+1 vs. 13–14+1, respectively); the number and arrangement of post cloacal papillae (6 pairs: 1st to 4th pairs ventral, 5th pair laterodorsal, 6th pairventral vs. five pairs: 1st and 2nd ventral, 3rd lateral, 4th ventral, 5th lateral); and by the size of spicules (413–600 vs. 85–126 µm).

Hysterothylacium gibsoni sp. nov. and H. tetrapteri (Bruce et Cannon, 1989) (Nematoda: Ascaridida) from the Chinese marine fishes

A new species of ascaridoid nematode, Hysterothylacium gibsoni sp. nov., is described based on specimens collected from the intestine of the slender lizardfish Saurida elongata (Temminck et Schlegel) (Aulopiformes: Synodontidae) in the Yellow Sea, China. The new species differs from its congeners by its small body size (12.8–13.2 mm), the absence of cervical alae, a very short intestinal caecum (representing 8.86–9.52% of oesophageal length) and a long ventricular appendix (intestinal caecum to ventricular appendix ratio 1:15.3–20.0), short spicules (0.38–0.41 mm, representing 2.97–3.11% of body length), the number and arrangement of the caudal papillae (25–28 pairs arranged as follows: 18–22 pairs precloacal, 3 pairs paracloacal, and 3–4 pairs postcloacal). In addition, Hysterothylacium tetrapteri (Bruce et Cannon, 1989) is also redescribed based on the material collected from the striped marlin Kajikia audax (Philippi) (Perciformes: Istiophoridae) in the South China Sea.

Location and development of larvae of Contracaecum rudolphii Hartwich, 1964 (Nematoda: Anisakidae) in experimentally infected asps Leuciscus aspius (Linnaeus, 1758) (Pisces: Cyprinidae)

Laboratory-reproduced and bred asps were experimentally infected with Contracaecum rudolphii larvae, either directly or with previously infected copepods. In the fish exposed to larval infection, the intensity and prevalence of infection were noticeably higher than in the group exposed to copepods. The course of larvae development was similar in both groups. In the larvae measuring ca. 1000 μm in length, the gastrointestinal tract with a developed ventriculus, ventricular appendix and intestinal caecum was clearly visible. The mouth was surrounded by three lips. Over the 10-week experimental period, slightly-coiled larvae surrounded with a thin theca but no encysted larvae were found in the fish exposed to larvae. On the other hand, spirally-stranded and encysted larvae were observed after the 7th week in the fish exposed to infected copepods. The results demonstrated that in the experimentally infected asps, the intensity and prevalence of infection as well as the location of the larvae in a fish depended on the type of invasive material applied.

A new species of Hysterothylacium (Nematoda: Anisakidae) from the giant mottled eel Anguilla marmorata in South Africa

A new species of ascaridoid nematode, Hysterothylacium anguillae sp. n. (family Anisakidae), is described based on specimens recovered from the stomach and intestine of the giant mottled eel Anguilla marmorata Quoy et Gaimard from the Mngazi River, South Africa, collected in March–April 2011. It is characterized mainly by poorly developed lateral alae, a very short intestinal caecum and a long ventricular appendix, spicules 1.11–2.14 mm long (representing 5.2–5.8 % of body length), number of caudal papillae (19–21 pairs of preanals, 2 adanals and 5 postanals), presence of a median precloacal papilla (= ventromedian organ), tail tips of both sexes covered by minute spines, and by the shape and structure of lips. This is the first nominal species of Hysterothylacium described from an African freshwater fish and the second species of this genus reported from freshwater eels of the family Anguillidae. The following Indian congeneric species are considered species inquirendae: Hysterothalacium aetobathum Lakshmi, 2005, H. carutti Lakshmi, Rao et Shyamasundari, 1993, H. channai Lakshmi, 1995, H. fossillii Lakshmi, 1996, H. japonicum Rajialakshmi, 1996, H. kiranii Lakshmi, 1993, H. longicaecum Lakshmi, Rao et Shyamansundari, 1993, H. narayensis Lakshmi, 1997, H. nellorensis Lakshmi, 1996, H. neocornutum Rajialakshmi, Rao et Shyamasundari, 1992 and H. punctati Lakshmi, 1995. Of them, H. japonicum and H. neocornutum are transferred to Iheringascaris Pereira, 1935 as I. japonica (Rajialakshmi, 1996) comb. n. and I. neocornuta (Rajialakshmi, Rao et Shyamasundari, 1992) comb. n.

Mawsonascaris parva sp. nov. (Nematoda: Ascaridida) from the Arabian whipray Himantura randalli Last, Manjaji-Matsumoto et Moore (Rajiformes: Dasyatidae) off the coast of Iraq

Mawsonascaris parva sp. nov. collected from the Arabian whipray Himantura randalli Last, Manjaji-Matsumoto et Moore (Rajiformes: Dasyatidae) off the coast of Iraq is described and illustrated using light and scanning electron microscopy. The new species differs from its congeners by its small body size (8.11–18.2 mm long), the absence of an intestinal caecum, the slightly unequal spicules (left and right spicule 1.08–2.50 mm and 0.98–2.01 mm long, respectively, representing 12.1–13.7% and 10.1–12.1% of body length), the number and arrangement of male caudal papillae (13–14 pairs in total, arranged as: 7–8 pairs of precloacal, 1 pair of double paracloacal and 5 pairs of postcloacal) and the presence of a single, median precloacal papilla. Thus, a total of six species of Mawsonascaris are now known and this is the first species of this genus recorded from species of Himantura.

A new species of Myxinidocotyle (Monogenea: Acanthocotylidae: Myxinidocotylinae) from captive sixgill hagfish, Eptatretus hexatrema (Chordata: Myxinidae), with amendment of the subfamily diagnosis

Myxinidocotyle eptatreti n. sp. is described from the skin of the sixgill hagfish, Eptatretus hexatrema collected for exhibition at the Two Oceans Aquarium in Cape Town, South Africa. The new species is the first acanthocotylid described from South Africa and differs significantly from the only two known Myxinidocotyle species by the morphology of the sclerotised male copulatory tube and the presence of a diverticulated intestinal caecum. The subfamily diagnosis is amended to include a single seminal receptacle, found within the anterior concave portion of the ovary and excludes the vaginal seminis receptaculum which is considered the seminal vesicle. The vagina travels ventrally over the seminal vesicle and does not fuse with it bilaterally as originally proposed by Malmberg & Fernholm (1989). Myxinidocotyle spp. possess 8 or 9 testes. The proximal male accessory gland reservoirs are connected by an intricate network of fine ducts to the field of extensive male accessory gland cells extending along the length of the body proper. Observations on the locomotion and attachment of live worms in vitro are discussed and the presence of adhesive secretions is confirmed for the haptoral glands and anterior glands.