Spirocerca vulpissp. nov. (Spiruridae: Spirocercidae): description of a new nematode species of the red fox,Vulpes vulpes(Carnivora: Canidae)

Previous studies have reported nematodes of the Spirocercidae family in the stomach nodules of red foxes (Vulpes vulpes) described asSpirocercasp. orSpirocerca lupi(Rudolphi, 1819). We characterized spirurid worms collected from red foxes and compared them toS. lupifrom domestic dogs by morphometric and phylogenetic analyses. Nematodes from red foxes differed fromS. lupiby the presence of six triangular teeth-like buccal capsule structures, which are absent in the latter. Additionally, in female worms from red foxes, the distance of the vulva opening to the anterior end and the ratio of the glandular-to-muscular oesophagus lengths were larger than those ofS. lupi(P< 0.006). In males, the lengths of the whole oesophagus and glandular part, the ratio of the glandular-to-muscular oesophagus and the comparison of the oesophagus to the total body length were smaller inS. lupi(allP< 0.044). Phylogenetic analyses revealed thatS. lupiand the red foxes spirurid represent monophyletic sister groups with pairwise nucleotide distances of 9.2 and 0.2% in the cytochrome oxidase 1 and 18S genes, respectively. Based on these comparisons, the nematodes from red foxes were considered to belong to a separate species, for which the nameSpirocerca vulpissp. nov. is proposed.

The functional anatomy of the anterior end of Skrjabinoptera goldmanae from Australian agamid lizards

Four muscle groups are responsible for the eversion and retraction of the apical denticles and enlarged pseudolabia in Skrjabinoptera goldmanae (Nematoda: Physalopteridae), which occurs in the lizards Chlamydosaurus kingii, Pogona spp. and Varanus gouldii in Australia. These muscles enable the nematode to bury its anterior portion in the gastric submucosa of its hosts. They comprise three sets which are derived from the somatic musculature and are inserted in the oesophagus and associated organs, and a fourth set of muscles which appears to be derived from the muscular oesophagus itself. These accessory muscle groups are described and illustrated, and from this their mode of action in everting and retracting the pseudolabia is derived. Possible selection pressures which led to their evolution are reviewed.

On some interesting nematode parasites of fish from Pakistan

Two interesting and unusual Spiruroid parasites have been reported from the intestines of marine fish. These are referred to the new genera and species, namely, Bulbocephalus inglisi and Cestocephalus serratus. The former is characterized by a globular head and the muscular oesophagus has two bulbs in its most anterior part. The glandular portion of this oesophagus is 20–25 times as long as the muscular part. The diganosis of Cestocephalus serratus is mainly based on the presence of an oblong head which is covered anteriorly by lobe-like structures in the manner of bothridia in some Cestodes. A new subfamily (family Spiruridae) has been proposed to accommodate Bulbocephalus gen.nov. The family or subfamily diagnosis of Cestocephalus gen.nov. has been restricted at present due to the paucity of material.The writer wishes to express her gratitude to Professor J. J. C. Buckley for his interest throughout this work.