A revision of the genus Alofia Giglioli, 1922 and a description of a new monotypic genus,Selfia: two genera of pentastomid parasites (Porocephalida: Sebekidae) inhabiting the bronchioles of the marine crocodile Crocodylus porosus and other crocodilians

The pentastomid genus Alofia Giglioli, 1922 (Porocephalida: Sebekidae), which is exclusively parasitic in the bronchioles of crocodiles, is reviewed. The type-species of the taxon, A. ginae Giglioli, 1922 from an unknown host allegedly taken in Samoa, had very distinctive, fine hooks with long slender blades bent at right angles. I describe a single female with identical hooks from the Philippines which was almost certainly derived from the marine crocodile Crocodylus porosus. This same host harboured two specimens of another Alofia species, tentatively identified as A. merki Giglioli, 1922, a species originally described with A. ginae (and, in all probability, from the same (unknown) host). Additional male and female specimens of A. merki, from several specimens of Australian C. porosus, re-affirm the characteristics of this species. Another new Alofia species, A. simpsoni, from an unknown host in Ghana, is established from measurements of two slide-mounted specimens (previously labelled Sebekia) from The Natural History Museum. There can be little doubt that its host is also a crocodile. A new monotypic genus Selfia is described, based on a type-series of 14 female and one male pentastomids dissected from the bronchioles of five specimens of C. porosus, all taken in Australia. Of the genera comprising the family Sebekidae (Alofia, Sebekia, Diesingia and Leiperia) Selfia is closest to the first, and its main diagnostic characteristics include a massive Alofia-like body, but with a markedly tapered, bluntly-rounded tail, and small, smooth ‘linear’ hooks with minute blades. The rear part of the anterior hooks are enveloped by a soft, cowl-like extension to the fulcrum, covered by small spines. The oral cadre is not U-shaped as in Alofia, but is more like that of Sebekia, whereas by contrast the male copulatory spicules of Selfia porosus and Alofia spp. are virtually identical, except in size. One previously described Alofia sp. from South American crocodilians is well characterized and valid, but two others are considered species inquirendae.     

Levisunguis subaequalis n. g., n. sp., a tongue worm (Pentastomida: Porocephalida: Sebekidae) infecting softshell turtles, Apalone spp. (Testudines: Trionychidae) in the southeastern United States

A new tongue worm (Pentastomida) belonging to the Sebekidae Sambon, 1922 (Porocephaloidea Sambon, 1922) is described based on exemplars collected from softshell terrapins Apalone spinifera aspera (Agassiz) and Apalone ferox (Schneider) in the southeastern United States; a new genus is erected to accommodate the new species. The new species belongs in the Sebekidae because adults possess four simple hooks arranged in a trapezoid pattern on the ventral surface of the cephalothorax, a mouth opening between the anterior and posterior pairs of hooks, a terminal anus, an elongated uterus with preanal uterine pore, and a Y-shaped seminal vesicle. Nymphs possess geminate hooks, and the new species has an aquatic life-cycle in which nymphs become encapsulated in the body cavity of a freshwater fish and mature in the lungs of a terrapin. The new genus is distinct from other genera in the Sebekidae primarily by differences in hook morphology and the fact that representatives use a terrapin as a definitive host. Nymphs infecting fish and presumed to be the new species matured as postlarval juveniles conspecific with the new species when they were fed to the eastern mud turtle, Kinosternon subrubrum (Lacépède). Nymphs of the new species are anatomically similar to but larger than nymphs of Sebekia mississippiensis Overstreet, Self & Vliet, 1985 found in the mesentery of fishes captured in Florida, U.S.A. Adults of the new species differ from those of S. mississippiensis based on hook features, chloride cell pore pattern on annuli, body size, and use of a turtle rather than crocodilian definitive host. The new species is the third North American member of the Sebekidae.     

Renivermis crocodyli (Digenea: Exotidendriidae) n. g., n. sp. from the kidneys of the saltwater crocodileCrocodylus porosus in Australia

Renivermis crocodyli, n. g., n. sp., is described from the kidneys of the saltwater crocodileCrocodylus porosus Schneider from northern Australia. The genusRenivermis is grouped withExotidendrium Mehra, 1935 andSimhatrema Chattopadhyaya, 1970 in the family Exotidendriidae Mehra, 1935. An amended diagnosis of the family and a key to its genera are given.     

A revision of the taxonomy of pentastomid parasites (genusRaillietiella Sambon, 1910) from American snakes and amphisbaenians

Summary Two species of pentastomid belonging to the genusRaillietiella Sambon, 1910 have been described from American snakes although their characters overlap and they are only differentiated on criteria now known to be unreliable (Self, 1969). We show that the species can be readily distinguished on the sole criterion of the form of the male copulatory spicule. There is confusion in many of the early records about hosts. After untangling these records, as far as possible, we postulate that the two species have allopatric distributions, one being Neotropical and the other Nearctic. A new species,R. crotali, is described, which is close to the Neotropical speciesR. furcocera, but it has much smaller hooks. Closely related species from the Old World utilize vertebrates as intermediate hosts and this is almost certainly true of the species described here. Given this, the very considerable differences in dietary regimen of the various hosts harbouring R. furcocerca, strongly suggest that there may be more than one species involved. R. gigliolii from the South American amphisbaenianAmphisbaena alba is also described since, historically, it has been confused withR. furcocerca. The systematics of these snake and amphisbaenian raillietiellids is discussed. ac]19821203     

Raillietiella trachea n. sp., a pentastomid from the trachea of an oriental white-backed vulture Gyps bengalensis taken in Pakistan,with speculation about its life-cycle

A cephalobaenid pentastomid, Raillietiella trachea n. sp., from the trachea of a fledgling oriental white-backed vulture Gyps bengalensis taken in Punjab Province, Pakistan, is described. This is the first record of a pentastomid from a fully terrestrial bird. Overall, gross morphology was typical of Raillietiella Sambon, 1910 in most respects. However, the hooks of R. trachea were of equal size, whereas in other members of the genus anterior hooks are smaller than the posterior hooks. The diagnosis of R. trachea was made on the basis of four near-patent females, all of which contained relatively few eggs (c.570), all at the same stage of maturity. Comparison with the only other genus known to infect birds (two species of Reighardia Ward, 1899 from the air-sacs of marine birds) revealed striking parallels in this aspect of the functional anatomy of the female reproductive tract. As far as we know, this mode of egg-production is not found in other raillietiellids. Extrapolating primarily from the experimental life-cycle studies of Reighardia sternae (Diesing, 1864) Ward, 1899, we surmise that the life-cycle of R. trachea has to be direct and that parasite behaviour is an integral part of parasite transmission. The evidence suggests that transmission is from vulture-to-vulture, per os.     

Some remarks on the taxonomy of Antarctic Leuconidae (Cumacea: Crustacea) with a description of a new speciesLeucon intermedius n. sp.

The newly described speciesLeucon intermedius n. sp. differs from other knownLeucon species by an inconspicuous antennal notch and the presence of only a few teeth at the dorsomedian crest. The species most similar toLeucon intermedius areL. septemdentatus andL. inexcavatus from the Antarctic/Subantarctic Ocean. A Table is given to allow direct comparison of the characteristics of allLeucon species known from the Antarctic/Subantarctic, Ocean. Forty-one specimens ofLeucon intermedius n. sp. were collected at depths ranging from 109 to 791 m in the vicinity of the Amery Depression (Indian Sector) and near King George Island (South Shetland Islands). Problems in distinguishing the Antarctic/Subantarctic species of the genusEudorella are discussed. The shape of the antennal notch is suggested as a better characteristic to distinguish theEudorella species than the proportions of the articles of extremities. On the basis of this criterion, samples at the Zoological Museum, Hamburg are made up of two species ofEudorella: gracilior and cf.fallax.     

The physiological arms race: Exploring thermal acclimation among interacting species

Thermal acclimation is often expected to increase performance during survival-related interactions, such as prey-capture and predator escape. However, few studies have examined acclimation responses in the context of the organism's ecology: namely, considering interactions among different species. In this study, we investigated the acclimation responses of three species of aquatic organisms from the same environment that simultaneously interact across different seasons. We predicted that the crimson spotted rainbowfish (Melanotaenia duboulayi) and the freshwater shrimp (Paratya australiensis), which are involved in a predator–prey relationship, would exhibit similar thermal acclimation responses due to an arms race in physiological responses. In contrast, we expected that the backswimmer (Enithares sp.) species from the same environment, which is not commonly preyed upon due to their hard chitinous exterior, would display a limited acclimation response. We found that acute increases in temperature resulted in improved locomotor performance for all three species and an improved prey capture performance for M. duboulayi. Acclimation to 15 °C or 25 °C for 6 weeks did not affect the prey-capture performance of M. duboulayi or the locomotor performance of either M. duboulayi or Enithares sp. However, acclimation to cool temperatures improved the locomotor performance of P. australiensis at both cool and warm temperatures. Thus, the interaction between M. duboulayi (predator) and P. australiensis (prey) is likely to change across seasons via differences in acclimation responses, which could directly affect their behavioural strategies and population dynamics.     

Fine structure of Leptomyxa ambigua n. sp. CCAP 1546/2 strain,formerly known as “Rhizamoeba flabellata” (Amoebozoa,Tubulinea, Leptomyxida)

The species Leptomyxa flabellata was described by Goodey in 1915 and re-isolated by Pussard and Pons in 1976. It seems that it was never seen (or never recognized) again since that time. The strain designated as “Leptomyxa flabellata CCAP 1546/2” was studied by Cann in 1984, however the quality of the electron microscopic images of that time was poor. Based on the cyst structure and size characters, Page in 1988 suggested that this strain is not co-specific with Goodey’s Leptomyxa flabellata, but represents a species ‘Ripidomyxa’ australiensis Chakraborty and Pussard, 1985, nowadays known as Rhizamoeba australiensis. In the present paper light- and electron-microscopic images of CCAP 1546/2 strain, which is now lost, are provided. Based on the morphological evidences it is suggested to establish it in a rank of a new species, Leptomyxa ambigua n. sp. Neither “true” L. flabellata Goodey, 1915 nor original R. australiensis Chakraborty et Pussard, 1985 are nowadays represented in the culture collections, and no original type material is available on both these species.     

A redescription ofLepidauchen stenostoma Nicoll, 1913 (Digenea), and a reassessment of the status of the genusLepidauchen Nicoll, 1913

The genusLepidauchen is discussed and defined. It is removed from the family Lepocreadiidae and placed in the family Acanthocolpidae based mainly on its possession of a uterine seminal receptacle. The type, and only valid species,L. stenostoma, is redescribed using material fromLabrus merula from Corsica. Material fromCoris julis andSymphodus tinca from the western Mediterranean off Marseille,L. merula from the western Mediterranean off Valencia,Diplodus annularis andLithognathus mormyrus from the Adriatic Sea off Montenegro, andArchosargus unimaculatus from Venezuela was also examined. Other nominal species are discussed, but none are considered valid within this genus.     

Primary Analysis of the Expressed Sequence Tags in a Pentastomid Nymph cDNA Library

Background

Pentastomiasis is a rare zoonotic disease caused by pentastomids. Despite their worm-like appearance, they are commonly placed into a separate sub-class of the subphylum Crustacea, phylum Arthropoda. However, until now, the systematic classification of the pentastomids and the diagnosis of pentastomiasis are immature, and genetic information about pentastomid nylum is almost nonexistent. The objective of this study was to obtain information on pentastomid nymph genes and identify the gene homologues related to host-parasite interactions or stage-specific antigens.

Methodology/Principal Findings

Total pentastomid nymph RNA was used to construct a cDNA library and 500 colonies were sequenced. Analysis shows one hundred and ninety-seven unigenes were identified. In which, 147 genes were annotated, and 75 unigenes (53.19%) were mapped to 82 KEGG pathways, including 29 metabolism pathways, 29 genetic information processing pathways, 4 environmental information processing pathways, 7 cell motility pathways and 5 organismal systems pathways. Additionally, two host-parasite interaction-related gene homologues, a putative Kunitz inhibitor and a putative cysteine protease.

Conclusion/Significance

We first successfully constructed a cDNA library and gained a number of expressed sequence tags (EST) from pentastomid nymphs, which will lay the foundation for the further study on pentastomids and pentastomiasis.     

Mesocyclops (Crustacea, Copepoda, Cyclopidae) in the South Pacific islands

Based mainly on recently collected material, we discuss the taxonomy and zoogeography of a (sub)tropical genus, Mesocyclops, in the South Pacific. A new species, Mesocyclops roberti sp. nov. is described from Fiji and the Wallis Islands. New data on the geographic distribution and morphology are reported for Mesocyclops medialis, Mesocyclops woutersi and Mesocyclops aspericornis. Phylogenetic reconstructions coding the intraspecifically variable characters by three different methods (unordered, unscaled and scaled coding) support close relationship of M. roberti with two Australian species (Mesocyclops brooksi and Mesocyclops notius). Both the “unordered” and “scaled” analyses show monophyly of a group composed of Australian (Mesocyclops australiensis, M. brooksi, M. notius, and Mesocyclops pubiventris) and South Pacific (M. medialis and M. roberti sp. nov.) taxa. None of the analyses supports a sister relationship of M. roberti with M. medialis (New Caledonia, Vanuatu), the only other species restricted to South Pacific, which suggests that Mesocyclops invaded the South Pacific from Australia at least twice. The sister relationship of the Australian-South Pacific clade remains unresolved, yet all reconstructions suggest a link with Asian Mesocyclops sp.     

Leydigia louisi louisi Jenkin, 1934 in the Neotropics, L. louisi mexicana n.subsp. in the Central Mexican highlands

Leydigia louisi Jenkin, 1934 was recently redescribed by Kotov (2003). We found in Guatemala and South of Mexico populations of this species, similar with the typical African form. A re-examination of Daday's (1902) specimens from Patagonia demonstrated that his material, determined as L. leydigi, was also L. louisi. At the same time, we describe a new subspecies Leydigia louisi mexicana n.subsp. from four water bodies on the central Mexican plateau (State of Mexico). Parthenogenetic females, ephippial females, juvenile and adult males are described. SEM illustrations are given for L. louisi mexicana n.sp. It differs from the nominotypical subspecies by (1) ocellus of irregular shape; (2) chitinous insertions within distal segments of swimming setae far from bases of segments; (3) on IDL, 3 bunches of very long setules; (4) setules on distal lobe of limb II long; (5) longest seta of exopodite III with long, fine setules; (6) seta 1 of exopodite IV relatively short; (7) a two-lobed body on inner margin of limb V. Features 2–6 were never used in the genus previously, but were applied in the systematics of other genera of Chydoridae. The ranges of these two subspecies are, probably, the Neotropical and Holarctic regions.     

Agonosoma trilineatum (Heteroptera: Scutelleridae) a biological control agent of the weed bellyache bush,Jatropha gossypiifolia (Euphorbiaceae)

Bellyache bush, Jatropha gossypiifolia L., is a serious weed of northern Australia. Agonosoma trilineatum (F.) is an insect from tropical America released in Australia in 2003 as a biological control agent against bellyache bush. It feeds on seeds and has the potential to reduce seed production, thereby potentially reducing the rate of spread and recruitment. To test the host specificity of A. trilineatum, four biological responses to host plant species were determined: development of nymphs, oviposition preferences, adult feeding and frequency of mating. Development of nymphs to adults and adult feeding only occurred on three Jatropha spp. These species also supported mating and oogenesis but only J. gossypiifolia was accepted for oviposition. Mating did not occur in the presence of other plant species. The evidence indicates that there is little risk associated with the release of this insect species in Australia and probably other countries where this weed is a problem. The probability of this insect expanding its host range is low because multiple aspects of the biology would need to change simultaneously. A. trilineatum was released in Australia between 2003 and 2007. A Climex model indicated that coastal areas of Queensland and the Northern Territory would be climatically most suitable for this insect.     

Studies on Lethrinitrema Lim & Justine, 2011 (Monogenea: Dactylogyridae), with the description of two new species,a key to the genus and a phylogenetic analysis based on rDNA sequences

Six species of Lethrinitrema Lim & Justine, 2011, including two new taxa, are described from the gills of Lethrinus nebulosus (Forsskål) from the South China Sea. Lethrinitrema nebulosum n. sp. differs from all other members of the genus in possessing a copulatory organ with a short, distally recurved tube, a cup-shaped base and a thin accessory piece, arising from distal end of tube, junction inconspicuous. Lethrinitrema zhanjiangense n. sp. can be distinguished from its congeners by possessing a copulatory organ with a C-shaped tube, a cup-shaped base and without accessory piece. Lethrinitrema grossecurvitubum (Li & Chen, 2005) n. comb. and Lethrinitrema austrosinense (Li & Chen, 2005) n. comb., previously included in Haliotrema Johnston & Tiegs, 1922, are transferred to Lethrinitrema and redescribed with additional details, including the intestinal caeca that unite posterior to gonads and continue posteriorly as two diverticula, and the elongate tubular distal end of each haptoral reservoir bifurcating prior to entering a superficial lateral groove on each side of the ventral anchor. The sclerotised parts of two unidentified species of Lethrinitrema are also described. Lethrinitrema sp. 1 differs from the other Lethrinitrema spp. in possessing a male copulatory organ consisting of a short tapered tube with a robust cup-shaped base and in lacking accessory piece. Lethrinitrema sp. 2 differs from its congeners in possessing a copulatory organ comprised of a short slender tube and without accessory piece, delicate ventral and dorsal bars, and poorly developed outer roots of the anchors. Sequences of partial 28S rDNA (domains D1–D2) and complete 18S rDNA for 27 dactylogyrids including five species of Lethrinitrema, i.e. Lethrinitrema fleti (Young, 1968) Lim & Justine, 2011, L. nebulosum, L. zhanjiangense, L. grossecurvitubum and Lethrinitrema sp. 1 were used to assess the monophyly of Lethrinitrema which was supported by high bootstrap values.     

Redescription of Heliconema africanum (Linstow, 1899) n. comb. (Nematoda: Physalopteridae), a nematode parasite of freshwater eels (Anguilla spp.) in South Africa

The little-known nematode species Heliconema africanum (Linstow, 1899) n. comb. (Physalopteridae) is redescribed based on light and scanning electron microscopical examinations of specimens collected from the stomach of the African longfin eel Anguilla mossambica (Peters) in the Nahoon River, Eastern Cape Province, South Africa. This species, previously misidentified as Heliconema longissimum (Ortlepp, 1922), is a common parasite of eels in South Africa. The systematic status of H. longissimum, a species originally described from unidentified Australian snakes, is unclear and probably several morphologically closely related species have been included under this name.