Phylogeny and taxonomy of Haloclavidae (Verrill, 1899) with a redescription of the parasitic, burrowing sea anemone, Peachia chilensis Carlgren, 1931.

Haloclavidae Verrill, 1899 is a family of burrowing sea anemones grouped within the superfamily Actinioidea (Rafinesque, 1815). Currently, it includes 30 species in 10 genera. Characters given for this family in descriptions of its taxa have not been consistent, with numerous exceptions to the expectations of the familial diagnosis. Previous phylogenetic analyses have shown that Haloclavidae is potentially a polyphyletic group, but resolution of relationships of the few representatives of Haloclavidae included in analyses has been problematic. Here we address questions of monophyly and affinity of Haloclavidae using three mitochondrial and two nuclear markers. We assess the monophyly of Haloclavidae in the context of all major lineages of Actiniaria Hertwig, 1882, emphasizing diversity of superfamily Actinioidea. We use parsimony-based character optimization to interpret the distribution of key traits in the superfamily. We find that Haloclavidae is not monophyletic and propose two new families, Peachiidae fam. nov. and Harenactidae fam. nov., while also retaining some species in the family Haloclavidae, so that taxonomy better reflects relationships and diversity of the group. In addition, we redescribe a species within the newly created Peachiidae, Peachia chilensis Carlgren, 1931. We use recent larval samples obtained in Antofagasta, Chile, and the histological slides from the original description to redescribe P. chilensis, to provide a complete account of cnidae, external, and internal morphology. Finally, we compare P. chilensis to other burrowing anemones found in Chile and provide an understanding of the genus Peachia that reflects recent phylogenetic perspective on diversity of anemones previously assigned to family Haloclavidae.

Aspects of the life history of Muspicea borreli (Nematoda: Muspiceidae), parasite of the house mouse (Mus domesticus) in Australia.

Prevalence of Muspicea borreli (Nematoda) infection in wild populations of Mus domesticus in forests in southeastern New South Wales and in rural Canberra, Australia was variable, relatively low and the parasite occurred predominantly in male mice. Experimental infection of BALB/c mice occurred only via subcutaneous inoculation but was achieved using i) adults containing embryonating eggs, ii) adults containing active larvae and iii) active larvae dissected from the uterus of female worms. Experimental infection was not established using adults containing unembryonated eggs and was not established via intraperitoneal, percutaneous nor oral routes. Evidence indicates that larvae develop to the infective stage in the uterus of the adult worm, suggests that an obligate developmental phase on the host skin does not occur and that autoinfection is possible. Experimental infection predominated in males; females rarely became infected. When male BALB/c mice were inoculated subcutaneously with M. borrelia, immediately paired with an uninoculated female and permitted to breed for 90 days, infection was found in male and female offspring only of the second and subsequent litters or in the breeding female partner. Transmission to the young occurred within 21 days of birth and fifth-stage M. borrelia were found in offspring of the second and subsequent litters only after 35 or more days. However, when a male was inoculated but mating delayed for 23 days, infection was found in progeny of the first and second litters. The life cycle is direct and the prepatent period in BALB/c mice is estimated at 50-60 days. The precise mode of transmission of the parasite in breeding pairs of mice was not determined but larvae remained active for approximately an hour in balanced saline solutions (pH = 7.2) and in human saliva but died under conditions emulating free-living (tap water pH = 7.1) and stomach (pepsin solution pH = 2) environments. Transmission was not effected by transplacental, transmammary nor transseminal routes. Consequently, it is difficult not to conclude that transmission may occur via penetration of skin or mucous membranes, and allogrooming behaviour may be particularly important in this regard.

Ultrastructure of Gonionchus australis (Xyalidae, Nematoda).

Observations are reported on the ultrastructure of the buccal cavity, body cuticle, spermatids, spermatozoa, male genitalia, and caudal glands of Gonionchus australis. The buccal cuticle is a continuation of the pharyngeal cuticle. Anteriorly it is secreted by arcade tissue and overlaps the mouth rim; laterally it forms longitudinal tooth ridges. The non-annulated cephalic cuticle differs sharply from the remainder of the body wall cuticle. The cortical and basal zones become much thinner, while a largely structureless, lucent median zone expands to fill the bulk of the lips and lip flaps. Spermatids possess fibrous bodies, multimembrane organelles, mitochondria, and compact chromatin. The spermatozoa of G. australis resemble those of most other nematodes by the absence of the nuclear envelope and presence of fibrous bodies, mitochondria, and compact chromafin. The ejaculatory duct possesses microvilli. Two ejaculatory glands lie beside the duct. Two neurons are located within each spicule and each part of the paired gubernaculum. Caudal gland nuclei are large, with dispersed chromatin. The ducts of all three caudal glands are filled with secretory vesicles.

Fine Structure of the Head and Cervical Region of Ceramonema carinatum (Chromadorida: Ceramonematidae).

Structure of the head and cervical region of Ceramonema carinatum (Chromadorida: Ceramonematidae) was described from transmission electron microscopy of serial transverse and longitudinal sections of two females. An unbroken massive cortical layer encompasses the head, except where three thin liplets surround the mouth. A large flask-shaped buccal cavity, with simpler less dense cuticle identical with that of the pharynx, abuts the body cuticle just within the mouth. Myoepithelial ceils constituting the buccal and pharyngeal regions were described. Sixteen head sensilla, the amphids, and dorsal and ventral internal sensilla were identified and described, each with associated sheath and socket cells. Ultrasturcture of the head was compared with that of other nematodes. Arrangement of sensilla resembled that of Monhysterida and Rhabditida with some significant variations, such as prominent longitudinally arranged intracellular organelles containing many microtubules associated with the amphids. The buccal cavity was almost entirely pharyngeal in character. A well-developed system of structural fibrils and abundant hemidesmosomes were notable features.

Structure of the Cuticle of Ceramonema carinatum (Chromadorida: Ceramonenatidae).

The cuticle of Ceramonema carinatum (Chromadorida: Ceramonematidae) is described and illustrated from scanning and transmission electron microscopy. Each of ca. 200 annules is composed of a single ring with eight external flat faces (plates), which are divided by longitudinal ridges formed by pairs of parallel upstanding vanes. Vanes and plates overlap those of the adjacent annules. Longitudinal ridges extend from the cephalic capsule to the tail spike. On the cephalic capsule a simple ridge extends each of the eight ridges to a position just anterior to the amphid. Cuticular plates are formed from the electron-dense cortical layer and contain lacunae filled with fine fibrils. The vanes are denser, with laminations on a central core. In the annular grooves between the plates there is an electron-lucent layer, which it is suggested, by comparison with other nematodes, is the basal layer. An epicuticle overlies the cortical plates, the vanes, and the interannular lucent layer. Cuficular structure is compared with that of other Ceramonematidae and related nematodes.

Observations on Crystalloid Bodies in the Pseudocoelom of Eutobrilus heptapapillatus.

Eutobrilus heptapapillatus, found in a number of different sites at the mouth of the River Murray in South Australia, were examined under light and electron microscopes. The pseudocoeloms of these nematodes often contained oval crystalloid bodies containing carbohydrate, sulfur, phosphorus, and lipid. The bodies varied considerably in size up to a maximum of 10 mum long. The precise function of these crytalloids remains unknown. Nematodes having these crystalloids often also contained numerous small regular densely staining particles, about 20 nm d and occurring throughout the nematode's body.

Structure of the Cuticle of Metadasynemoides cristatus (Chromadorida: Ceramonematidae).

Structure of the cuticle of Metadasynemoides cristatus (Chromadorida: Ceramonematidae) is examined by light, scanning, and transmission electron microscopy. The nematode has more than 600 annuli, and each annulus has eight cuticular plates. Eight longitudinal ridges, beginning on the cephalic capsule, extend the whole length of the body. Where a ridge traverses an annulus, it forms a complicated articulating structure of overlapping vanes. Within the electron-dense cortical layer, from which the cuticular plates are formed, there are spaces crossed by fine fibrillae, forming what have been termed "vacuoles" by light microscopists. There is an epicuticle and a continuous lucent basal layer. There appears to be no median layer. The cuticle lining of the esophagus and that forming the circum-oral ridge is of much simpler construction.

Toxocariasis: a serological survey of blood donors in the Australian Capital Territory together with observations on the risks of infection.

The sera from 660 healthy blood donors from Canberra were tested for antibodies to Toxocara canis by the ELISA test. The results were compared with those from patients with suspected or confirmed visceral larva migrans or ocular toxocariasis. Over 7% of Canberra sera showed elevated levels of antibody reacting with T. canis antigen. Sera from patients resident in Australia with other helminth parasites did not cross-react with T. canis antigen in our tests. However, studies of sera collected in several tropical countries with other parasitic infection, show that cross-reactions with other parasites are possible. The use of purified glycoprotein antigen does not alter the possibility of cross-reaction. Observations and experiments show that people in Canberra may be exposed to the infective eggs of T. canis.

Biosynthetic labelling of the excretory and secretory antigens of Toxocara canis larvae.

Toxocara canis larvae were cultured in vitro in medium containing [35S-]methionine for six days. The medium and the larval tissues were analysed for biosynthetically labelled polypeptides by sodium dodecyl sulphate polyacrylamide gel electrophoresis and autoradiography. Immunoprecipitates with positive and negative human antiserum were similarly analysed, using Staphylococcus aureus to absorb immunocomplexes. The larvae secrete biosynthetically labelled polypeptides into the medium, with three major polypeptides of molecular weights between 99 and 110 X 10(3) the major constituents. Both of these react strongly with human IgG in human positive sera. Many polypeptides become labelled in the larval tissue, but only one polypeptide with similar molecular weight to the ES antigens, strongly reacted with human IgG.

In vitro translation of mRNA from Toxocara canis larvae.

300 micrograms of total RNA was extracted from 1 ml of packed Toxocara canis larvae by centrifugation through a 5.7 M cesium chloride cushion. 60 micrograms of polyadenylated messenger RNA was separated from 300 micrograms of total RNA in an oligothymidylic acid-cellulose gel column. The in vitro translation of the mRNA, isolated from T. canis larvae, was carried out using the rabbit reticulocyte cell-free translation system. Incorporation of [35S]methionine into trichloroacetic acid precipitable material in the lysate containing mRNA was 4-5 times greater than that of control. Translation products were analysed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by autoradiography. Many polypeptides ranging in molecular weight from 10000 to 100000 were synthesised in the lysate. A T. canis positive human serum was mixed with translation products to form antigen-antibody complexes, which were then absorbed by Staphylococcus aureus Cowan 1 strain and analysed by the autoradiography of SDS-PAGE. Three antigenic polypeptides with molecular weights of 49000, 27000 and 22000 which reacted specifically with IgG antibody in T. canis positive human serum, were demonstrated. The 27000 MW polypeptide reacted particularly strongly with the IgG antibody.

Antibody responses to Toxocara canis using sera from parasite-infected mice and protection from toxocariasis by immunisation with ES antigens.

Evidence for serological cross-reactions between Toxocara canis and related nematode parasites has been sought using sera from infected mice and the immunodiagnostic excretory/secretory (ES) antigen of T. canis larvae. Sera from mice experimentally infected with either T. canis, T. cati, T. pteropodis, Toxascaris leonina or Ascaris suum were tested for the presence of antibodies to T. canis ES antigen by solid-phase radioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA) using anti-mouse IgG. T. canis ES antigen was obtained from the medium used to culture T. canis larvae, this being the same source of antigen as has been used in a highly satisfactory immunodiagnostic test for human toxocariasis (visceral larva migrans). Sera from mice infected with either A. suum, T. cati or T. pteropodis showed definite cross-reactions with T. canis ES antigen in one or other of the two essays used. No reaction between anti-T. leonina sera and T. canis ES antigen was demonstrated, although infection levels with this parasite were low in mice. Concerning biological activity of ES antigen, it is of some interest that mice hyperimmunised with T. canis ES antigen in adjuvant were shown to be significantly resistant to infection by T. canis.

Peritoneal cell population of mice infected with Mesocestoides corti as a source of eosinophils.

A prominent feature of the inflammatory cellular response in the peritoneal cavity of Mesocestoides corti-infected mice is a marked and sustained increase in the number of eosinophils. In intact mice, the total number of nucleated cells in the peritoneal cavity rises from less than 5 X 10(6) to more than 50 X 10(6) and, at certain time points, in excess of 50% of these cells are eosinophils. Peritoneal eosinophils are absent in infected hypothymic nude (nu/nu) mice of three genotypes, and eosinophils counts can be elevated in infected nude mice by injection of peripheral lymphoid cells or thymocytes. The peritoneal cells of M. corti-infected mice are a convenient starting cell population for eosinophil purification.

Hospital records of hydatid disease in Victoria for 1970 to 1974.

The records of hydatid disease in 10 Melbourne hospitals and 12 rural hospitals in Victoria from 1970 to 1974 have been studied. In a total of 183 in-patients, the final diagnosis of hydatid disease had been confirmed surgically in 81 first admissions and in 56 readmissions. In 24 cases it was confirmed by necropsy, but in only one of these was hydatid disease believed to have been the cause of death. Figures are given for the age distribution and the organs involved.

The control of hydatid disease and ovine cysticercoses in the Australian Capital Territory and southern New South Wales.

A survey of human hydatid disease in New South Wales and the Australian Capital Territory over the period 1968 to 1973 was made from hospital records in Sydney and Canberra. The 162 new cases found represent an incidence, of 0-57 per 100,000 per annum, but the 20 patients living in the Central West Statistical Division of New South Wales at the time of admission to hospital represent an incidence of 12-6 per 100,000 per annum in that area. A survey of A.C.T. farms revealed dogs carrying the causative parasite Echinococcus granulosus on five out of 44 properties (11-4%). Community attitudes favoured control measures but displayed a misplaced faith in anthelmintic drugs. The high regional prevalence on the Australian mainland reveals a need to restrict availability of anthelmintics and extend the vigorous control measures employed successfully in Tasmania.