A New Isospora (Apicomplexa: Eimeriidae) from the Summer Tanager, Piranga rubra (Aves: Passeriformes: Cardinalidae), in Oklahoma.

The summer tanager, Piranga rubra (L., 1758) is a medium-sized songbird formerly belonging to the tanager family Thraupidae but now has been placed within the family Cardinalidae. Nothing is known about the coccidian parasites of this stunningly colorful bird. Feces from 2 P. rubra found dead in McCurtain County, Oklahoma were collected and examined for coccidia; 1 was found to be passing a new species of Isospora. Oocysts of Isospora mccurtainensis n. sp. are subspheroidal to ovoidal with a smooth bilayered wall, measure (length × width [L × W]) 21.7 × 19.5 µm, and have a L/W ratio of 1.1; a micropyle and oocyst residuum were absent but a bilobed and refractile polar granule is present. Sporocysts are ellipsoidal and measure 13.9 × 8.6 µm, L/W 1.6; a knoblike Stieda body is present as well as a distinct sub-Stieda body. The sporocyst residuum is composed of a granular compact cluster with a dense, irregular mass of granules lying between and dispersed among the sporozoites. This is the first coccidian reported from P. rubra and, most important, only the first known from the Cardinalidae in the mainland of the United States.

A New Isosporan (Apicomplexa: Eimeriidae) from Wood Thrush, Hylocichla mustelina (Aves: Passeriformes: Turdidae), in Oklahoma.

The wood thrush, Hylocichla mustelina, is a North American passerine bird closely related to other thrushes and is widely distributed across North America. Nothing is known of the coccidian parasites of this bird. Feces from a single H. mustelina found dead in McCurtain County, Oklahoma were collected and examined for coccidia; it was found to be passing a new species of Isospora. Oocysts of Isospora gmelini n. sp. are subspheroidal to ellipsoidal with a smooth bilayered wall, measure (length [L] × width [W]) 19.5 × 16.5 µm, and have a L/W ratio of 1.2; a micropyle and oocyst residuum were absent but polar granule(s) are present. Sporocysts are ellipsoidal to elongate and measure 13.4 × 8.9 µm, L/W 1.5; a buttonlike Stieda body is present, but sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of a compact spheroid with a dense, irregular mass of finer granules lying between and dispersed among the sporozoites. Although several isosporans have been reported from other turdid birds, mainly from Brazil and Costa Rica, this is the initial coccidian reported from H. mustelina and only the second known from the Turdidae in the mainland of the United States.

A New Species of Rhinergasilus Boeger et Thatcher, 1988 (Copepoda: Ergasilidae) from Gills of Astyanax fasciatus (Cuvier, 1819) (Actinopterygii: Characidae).

PURPOSE: To describe a new species of a parasitic copepod, Rhinergasilus digitus n. sp. (Cyclopoida, Ergasilidae), collected from the gills of the red-tailed lambari Astyanax fasciatus (Characiformes, Characidae) in two tributaries of the Jurumirim Reservoir (Upper Paranapanema River), São Paulo State, Brazil: Ribeirão dos Veados and Paranapanema River. METHODS: Fish were collected using multi-panel gills nets. The gill of each fish was washed and examined in a stereo microscope for copepods. The copepods found were stored in 70% ethanol, cleared in lactic acid, and mounted in Hoyer's medium. Drawings were made with the aid of a Leica microscope DMLS equipped with a drawing tube. RESULTS: The new species differs from its congeneric species, Rhinergasilus piranhus (type-species), in having comparatively biggest body size (body length: 535-598 µm in the new species vs. 237-282 µm in R. piranhus); second antennary segment armed with a minute sensillum near middle of inner margin and a row of spinules on outer margin; third exopodal segment of leg 1 with digitiform process; interpodal plates two and three both ornamented with spinules along posterior margin; leg 5 reduced and represented by two unequal setae. CONCLUSIONS: Based on the morphological differences described above, we erected a new species of Rhinergasilus. Rhinergasilus digitus n. sp. is the second ergasilid described from A. fasciatus, as well as it represents the first report of this genus in a characid fish.

Two Novel Myxozoans from Pirate Perch Aphredoderus sayanus (Gilliams, 1824) in the Upper Mississippi River, Including the First North American Species of Hennegoides Lom, Tonguthai, & Dyková, 1991.

The pirate perch Aphredoderus sayanus is a relatively small fish species found in rivers throughout much of the eastern United States. Due to their cryptic nature, relatively little is known regarding their parasite fauna. A survey of pirate perch from the upper Mississippi River revealed 2 novel myxozoans. Hennegoides flockae n. sp. was observed in heavily infected gills where the lamellae featured irregular expansion by bulbous myxozoan polysporic plasmodia, typically affecting the middle to distal half of the filaments. When severe, infection of sequential filaments was such that the filaments were fused, forming what appeared as multicystic/lobular parasitic aggregates subdivided by fine epithelial cords. The total myxospore length of Hennegoides flockae was 35.4-46.4 (41.3 ± 3.3) and the spore body, asymmetrically ovoid in valvular view, was 15.4-18.7 (17.0 ± 0.7) × 7.1-8.7 (7.9 ± 0.4). Henneguya marcquenskiae n. sp. was observed in the liver with plasmodia present randomly and infrequently in the hepatocellular parenchyma. The total myxospore length for Henneguya marcquenskiae was 39.5-55.9 (48.4 ± 4.2), with the spore body being lanceolate, 13.9-16.5 (15.4 ± 0.7) × 7.1-9.0 (8.3 ± 0.5). Phylogenetic analysis of the SSU rRNA gene placed both Hennegoides flockae and Henneguya marcquenskiae as sisters to each other in a clade containing other Myxozoans known to infect the gills of esocids, percids, and centrarchids. These parasites represent the first reports of Henneguya and Hennegoides from pirate perch, with the latter being the first report of this genus outside of the Asian continent.

A new quill mite Torotrogla emberizae sp. nov. (Acariformes: Syringophilidae) from the Chestnut-eared Bunting (Passeriformes: Emberizidae) in Japan (morphology and DNA barcode data).

A new quill mite Torotrogla emberizae sp. nov. (Acariformes: Syringophilidae) parasitizing the Chestnut-eared Bunting Emberiza fucata Pallas, 1776 (Passeriformes: Emberizidae) in Japan is described based on the external morphology and DNA barcode data (mitochondrial cytochrome c oxidase subunit I sequences, COI). Females of T. emberizae sp. nov. differ from T. volgini Skoracki and Mironov, 2013 by having the short, wide and blunt-ended hypostomal protuberances (vs long, thin and sharp-ended), setae h1 ca. twice shorter than f1 (vs h1 longer than f1), the fan-like setae p' and p" of legs III-IV provided with ca. 10 tines (vs 7-8 tines) and lengths of setae vi 70-105 (vs 55-65), ve 105-135 (vs 85-90) and h1 55-60 (vs 95-120).

Eimeria spp. infecting quenda (Isoodon obesulus) in the greater Perth region, Western Australia.

Parasites of wildlife inhabiting urbanised and peri-urban environments are of interest regarding wildlife population health, and also veterinary public health in the case of parasites that can also infect humans and domestic animals. This study aimed to: identify, and estimate the prevalence of, species of Eimeria parasitic in quenda (Isoodon obesulus) in the greater Perth region, Western Australia; 2) morphologically describe and genetically characterise a novel observed species of Eimeria as E. angustus; and 3) genetically characterise E. kanyana. Eimeria spp. prevalence was 76.1% (95% CI 64.9-84.5%), and four putative species of Eimeria were identified. Eimeria kanyana was identified infecting quenda for the first time, with a prevalence of 54.9% (43.4-66.0%). Eimeria quenda was less prevalent, at 7.0% (3.1-15.5%). The novel species E. angustus was present in 45.1% of sampled quenda (34.0-56.6%). A second novel morphotype of Eimeria was present in 2.8% of sampled quenda (0.9-9.7%). Mixed Eimeria spp. infections were present in 21/71 quenda (29.6%, 95% CI 20.2-41.1%). Molecular phylogenetic analyses of E. kanyana and E. angustus were conducted at the 18S rRNA and mitochondrial cytochrome oxidase loci. At both loci, two isolates identified as E. kanyana grouped in a phylogenetic clade with E. trichosuri. Five isolates identified as the novel E. angustus were most closely related to E. tropidura at the 18S locus. At the COI locus, no sequence data were available for E. tropidura; isolates of E. angustus grouped with E. sciurorum.

Two New Species of the Family Syringophilidae (Prostigmata: Syringophilidae) Parasitising Bushshrikes (Passeriformes: Malaconotidae).

Two new species of quill mites of the subfamily Syringophilinae Lavoipierre (Acari: Prostigmata: Syringophilidae) are described from the Bushshrikes (Passeriformes: Malaconotidae) in the Afrotropical region: Neoaulonastus malaconotus n. sp. parasitizing Telophorus nigrifrons (Reichenow) (Malaconotidae) [type host] in Liberia and Kenya, Laniarius aethiopicus (Gmelin) in Somalia, Nilaus afer (Latham) in Kenya, and Syringophiloidus nkaii n. sp. from Nilaus afer in Kenya.

Further characterisation of two Eimeria species (Eimeria quokka and Eimeria setonicis) in quokkas (Setonix brachyurus).

The identification and characterisation of novel Eimeria species has largely been based on sporulated oocyst and sporocyst morphology, the host species and the geographical range. Variation in the size and shape of Eimeria oocysts across their host range however, make the identification and characterisation of novel species using traditional methodologies alone problematic. The use of molecular markers and phylogenetic analysis has greatly advanced our ability to characterise Eimeria species and has recently been applied to understand evolutionary relationships among Eimeria species from Australian marsupials. In the present study, Eimeria species isolated from quokkas (Setonix brachyurus) captured from Two Peoples Bay, Bald Island and Rottnest Island, Western Australia, were morphologically identified as Eimeria quokka and Eimeria setonicis. Both Eimeria species were identified as being polymorphic in nature with regards to sporulated oocyst and sporocyst morphometrics. Phylogenetic analysis using 18S rRNA and COI (cytochrome c oxidase subunit 1) genes, grouped E. quokka and E. setonicis within the Eimeria marsupial clade together with Eimeria trichosuri from brushtail possums, Eimeria macropodis from tammar wallabies (Macropus eugenii) and several unidentified macropod Eimeria species from western grey kangaroos (Macropus fuliginosus). This study is the first to characterise E. quokka and E. setonicis by molecular analysis, enabling more extensive resolution of evolutionary relationships among marsupial-derived Eimeria species.

Gastrointestinal symbionts of chimpanzees in Cantanhez National Park, Guinea-Bissau with respect to habitat fragmentation.

One of the major factors threatening chimpanzees (Pan troglodytes verus) in Guinea-Bissau is habitat fragmentation. Such fragmentation may cause changes in symbiont dynamics resulting in increased susceptibility to infection, changes in host specificity and virulence. We monitored gastrointestinal symbiotic fauna of three chimpanzee subpopulations living within Cantanhez National Park (CNP) in Guinea Bissau in the areas with different levels of anthropogenic fragmentation. Using standard coproscopical methods (merthiolate-iodine formalin concentration and Sheather's flotation) we examined 102 fecal samples and identified at least 13 different symbiotic genera (Troglodytella abrassarti, Troglocorys cava, Blastocystis spp., Entamoeba spp., Iodamoeba butschlii, Giardia intestinalis, Chilomastix mesnili, Bertiella sp., Probstmayria gombensis, unidentified strongylids, Strongyloides stercoralis, Strongyloides fuelleborni, and Trichuris sp.). The symbiotic fauna of the CNP chimpanzees is comparable to that reported for other wild chimpanzee populations, although CNP chimpanzees have a higher prevalence of Trichuris sp. Symbiont richness was higher in chimpanzee subpopulations living in fragmented forests compared to the community inhabiting continuous forest area. We reported significantly higher prevalence of G. intestinalis in chimpanzees from fragmented areas, which could be attributed to increased contact with humans and livestock.

A new aporocotylid (Digenea) species from blood vascular system of gag grouper, Mycteroperca microlepis (Perciformes: Serranidae), off Alabama, with an emendation of Pearsonellum Overstreet & Køie, 1989.

Pearsonellum lemusi n. sp. (Digenea: Aporocotylidae) infects the blood vascular system of the gag grouper, Mycteroperca microlepis (Perciformes: Serranidae), in the north central Gulf of Mexico, approximately 80 km south of Dauphin Island, Alabama (29°34'09″N, 88°22'16″W). The new species can be most easily differentiated from its only congeners Pearsonellum corventum Overstreet and Køie, 1989 (type species) and Pearsonellum pygmaeus Nolan and Cribb, 2004 , both of which infect Australian serranids, by the combination of having a large adult body (3,237 × 570 µm), a cecal intersection comprising an elongated medial channel, anterior ceca >10% of total body length, ovary narrower than testis, and pre-ovarian uterus not looping between testis and ovary. The embryonated eggs of the new species infect gill epithelium, are spheroid, and measure 25-30 µm in diameter. Sympatric Gulf of Mexico serranids were negative for aporocotylid infections: coney, Cephalopholis fulva (n  =  1); Nassau grouper, Epinephelus striatus (3); red grouper, Epinephelus morio (32); yellowedge grouper, Epinephelus flavolimbatus (1); rock hind, Epinephelus adscensionis (1); red hind, Epinephelus guttatus (2); Warsaw grouper, Epinephelus nigritus (3); graysby, Cephalopholis cruentata (1); black grouper, Mycteroperca bonaci (1), and tattler, Serranus phoebe (2). The new species is the first aporocotylid described from a serranid outside of the southwestern Pacific Ocean. The diagnosis of Pearsonellum Overstreet and Køie, 1989 is herein emended to include anterior sucker having concentric rows of spines anterior to mouth, pharynx absent, esophagus length <1/2 total body length, vas deferens connecting with cirrus sac anteromedially, ovary occupying posterior 1/4-1/3 of body, primary vitelline duct dextral, and oviducal seminal receptacle extending posteriad in parallel with lateral body margin, not transverse nor constricted anteriorly or posteriorly by sharp bends or kinks.

A new species of Eimeria (Apicomplexa: Eimeriidae) from the eastern pipistrelle, Perimyotis subflavus (Chiroptera: Vespertilionidae), in Arkansas.

During November 2009 and March 2010, 20 adult eastern pipistrelles, Perimyotis (=  Pipistrellus) subflavus, were collected from Polk County, Arkansas, and their feces were examined for coccidian parasites. Two (10%) of the bats were found to be passing oocysts of an undescribed species of Eimeria. Oocysts of Eimeria heidti n. sp. were ovoidal to ellipsoidal, 26.1 × 20.5 µm (23-31 × 18-23 µm), with a bilayered wall, externally rough, internally smooth, and with a shape index of 1.3. Micropyle and oocyst residuum were absent, but a subspherical polar granule was often present. Sporocysts were ovoidal, 13.0 × 8.8 µm (11-15 × 7-13 µm), the shape index was 1.6, a Stieda body was present and sub-Stieda and para-Stieda bodies were absent. A sporocyst residuum consisting of multiple globules dispersed along the perimeter of the sporocyst and between the sporozoites were present, sporozoites were elongate, with a subspherical anterior refractile body and elongate posterior refractile body; a nucleus not discernible. This is the second coccidian reported from this host and the fourth instance of a coccidian species reported from an Arkansas bat.

Intracellular signaling cascades induced by relaxin in the stimulation of capacitation and acrosome reaction in fresh and frozen-thawed bovine spermatozoa.

Relaxin is one of the 6-kDa peptide hormones, which acts as a pleiotropic endocrine and paracrine factor. Our previous studies revealed that sperm capacitating medium containing relaxin induced capacitation and acrosome reaction (AR) in fresh and frozen-thawed porcine or bovine spermatozoa. However, the intracellular signaling cascades involved with capacitation or AR induced by relaxin was unknown. Therefore, the present study was designed to investigate the intracellular signaling cascades involved with capacitation and AR induced by relaxin in fresh and frozen-thawed bovine spermatozoa. Spermatozoa were incubated in sperm Tyrode's albumin lactate pyruvate (Sp-TALP) medium supplemented with (40 ng ml(-1)) or without relaxin, and subjected to evaluation of chlortetracycline staining pattern, cholesterol efflux, Ca(2+)-influx, intracellular cyclic adenosine monophosphate (cAMP) and protein tyrosine phosphorylation. Capacitation and AR were increased (P<0.05) in both fresh and frozen-thawed spermatozoa incubated with relaxin. Cholesterol effluxes were greater in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa incubated with relaxin than the spermatozoa incubated without relaxin. Ca(2+)-influxes were also significantly stimulated by relaxin in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa. The Sp-TALP medium containing relaxin influenced the generation of intracellular cAMP in the fresh (P<0.01) and frozen-thawed (P<0.05) spermatozoa, and exhibited higher exposure of protein tyrosine phosphorylation in both sperm types than the medium devoid of relaxin. Therefore, the results postulate that relaxin exerts the intracellular signaling cascades involved with capacitation and AR through accelerating the cholesterol efflux, Ca(2+)-influx, intracellular cAMP and protein tyrosine phosphorylation in fresh and frozen-thawed bovine spermatozoa.

A new genus and species of Brachycoeliidae (Digenea) from Chiropterotriton sp. (Caudata: Plethodontidae) in Mexico and its phylogenetic position within the Plagiorchiida based on partial sequences of the 28S ribosomal RNA gene.

Parabrachycoelium longicaecum n. gen., n. sp. (Digenea: Brachycoeliidae) is described from the intestine of a plethodontid salamander Chiropterotriton sp. Hosts were collected in bromeliads at the cloud forest of Tlaquilpa, Veracruz, Mexico. Members of the Brachycoeliidae Looss, 1899 (sensu Yamaguti, 1971) are characterized by having a spined tegument; ceca usually short, not passing level of gonads, but longer in some species; gonads posterior to, or in region of, acetabulum, with ovary anterior to testes; a well developed cirrus pouch containing a bipartite seminal vesicle; and uterus occupying entire hind-body posterior to testes. However, this combination of morphological traits prevents the inclusion of the new taxon in any of the genera in that family; a new genus was, therefore, erected to accommodate the new species. The new taxon is readily distinguished from members belonging to Brachycoelium Dujardin, 1845, Mesocoelium Odhner, 1910, and Tremiorchis Mehra and Negi, 1925, by having long ceca extending into the posterior third of the body, slightly surpassing the testes, and vitellaria extending along the body. The new species morphologically resembles Caudouterina rhyacotritoni Martin, 1966, a digenean parasitizing a plethodontid salamander; however, the latter species lacks spines in the tegument and is actually placed within the Allocreadiidae. To demonstrate further the phylogenetic position of the new taxon, we sequenced the D1-D3 regions of 28S rRNA gene and conducted a phylogenetic analysis of available sequences for the order to which brachycoeliids belong (Plagiorchiida). Sequence divergence of the partial 28S rRNA gene confirms its distinction from the aforementioned brachycoeliids, and the phylogenetic position within the Plagiorchiida places the new species as closely related to a clade formed by Brachycoelium + Mesocoelium. Divergence levels and phylogenetic position within the Plagiorchiida verifies the validity of the new genus and its inclusion in Brachycoeliidae.

Diploid spermatozoa caused by failure of the second meiotic division in a bull.

An artificial insemination bull (Bos taurus) exhibiting 23% macrocephalic spermatozoa in the ejaculate was investigated. Spermatozoa with a projected head area of > or = 52 microm(2) were considered macrocephalic. Diploidy was assumed from the measurement of sperm head area and proved by flow cytometry, which was used to sort the sperm into haploid and diploid fractions. Fluorescence in situ hybridization was used to detect the sex chromosomes with an X-Y probe set. Diploid spermatozoa most likely originate from a defective second meiotic division (M2 diploids), as only 0.7% XY-bearing spermatozoa (M1 diploids) were detected in the spermatozoa of the flow cytometric diploid sort. The painting probes generated a single X or Y spot for both unsorted semen and diploid sorted spermatozoa. This indicates a close proximity of the nonpartitioned sister chromatids in the spermatozoa. The BC1.2 probe, which labels BTAYp13-12, was used to clarify the presence of the two chromatids in the singular signal of the simultaneously hybridized Y-painting probe. In scoring more than 1000 randomly sampled spermatozoa hybridized with the BC1.2 probe, 32% showed the YY diploid signal and 18% the Y signal. The sperm diploidy in this bull was caused by an incomplete partitioning of sister chromatids during the second meiotic division (M2) associated with a failure in nuclear cleavage.

Why museums matter: a tale of pinworms (Oxyuroidea: Heteroxynematidae) among pikas (Ochotona princeps and O. collaris) in the American west.

Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only 2 species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependant on accurate and definitive information that transcends specific disciplines.

Two new species of Eimeria (Apicomplexa: Eimeriidae) from eastern red bats, Lasiurus borealis (Chiroptera: Vespertilionidae), in Arkansas and North Carolina.

During August 2003 and August 2004, 11 adult eastern red bats, Lasiurus borealis, were collected and their feces examined for coccidian parasites. Bats were obtained in August 2003 from Garland, Montgomery, and Yell counties, Arkansas (n=6) and in August 2004 from Anson and Montgomery counties, North Carolina (n=5). Seven (63.6%) of the bats were passing oocysts of 2 undescribed species of Eimeria. Oocysts of Eimeria dowleri n. sp. were subspherical to ellipsoidal, 24.7 x 22.0 (23-26 x 20-23) microm, with a bilayered wall, externally moderately pitted, internally smooth, and with a shape index of 1.1. Micropyle and oocyst residuum were absent, but a polar granule was present. Sporocysts were ovoidal, 13.4 x 9.2 (12-14 x 8-9) pm; shape index was 1.5; Stieda and sub-Stieda bodies were present. A sporocyst residuum consisting of homogeneous granules was scattered among the sporozoites; sporozoites were elongate, with a subspherical anterior refractile body and an elongate posterior refractile body; a nucleus was not discernable. Oocysts of Eimeria sealanderi n. sp. were subspherical to ellipsoidal, 16.7 x 14.4 (15-18 x 13-16) microm, with a bilayered wall, externally lightly pitted, internally smooth, and with a shape index of 1.2. A micropyle was absent, but the oocyst residuum and polar granule were present. Oocyst residuum consisted of a single, membrane-bound homogenous granule. Sporocysts were ovoidal, 8.9 x 5.7 (8-10 x 5-6) microm, with a shape index of 1.6; Stieda and sub-Stieda bodies were present. The sporocyst residuum consisted of 10, to several dozen, homogeneous granules of various sizes loosely clustered among the sporozoites, which were elongate and without obvious refractile bodies and nucleus. This is the first time any coccidian has been reported from this host and the first instance of a bat coccidian reported from North Carolina.

Nitric oxide: An autocrine regulator of Leydig cell steroidogenesis in the Asian catfish, Clarias batrachus.

Nitric oxide has been recognized as an important inter- and intra-cellular modulator of testicular steroidogenesis in higher vertebrates with conflicting results. Moreover, its role in regulation of testicular steroidogenesis in ectothermic vertebrates is non-existent. The present study was, therefore, undertaken to examine whether Leydig cells of a freshwater catfish, Clarias batrachus produce nitric oxide (NO), if so, does it regulate its steroidogenic activity? The purified Leydig cells were stained histochemically for NADPH-diaphorase (NADPH-d) activity, and immunocytochemically for neuronal and inducible nitric oxide synthase (nNOS and iNOS) like molecules. Leydig cells were also incubated with NOS inhibitor, N-nitro-l-arginine methyl ester (l-NAME), and NO donor, sodium nitroprusside (SNP). NO and testosterone released in incubation medium were analyzed. A distinct positive NAPDH-d staining was observed in Leydig cells. These cells also exhibited immunoprecipitation of variable intensity with nNOS and iNOS antibodies. Further, l-NAME treatment caused significant suppression in NO production and elevation in testosterone secretion by Leydig cells. On the contrary, exposure of Leydig cells to SNP resulted in increased NO production with concomitant decline in testosterone level. Thus, the present study reports NO production by Leydig cells in fish for the first time, which appears to inhibit its own androgen production.

A New Species of Eimeria (Apicomplexa: Eimeriidae) from the marbled salamander, Ambystoma opacum (Caudata: Ambystomatidae), from northern Louisiana.

Between December 2002 and June 2004, 10 marbled salamanders, Ambystoma opacum, were examined for coccidian parasites. Salamanders were collected in Bradley (n = 2), Little River (n = 1), Miller (n = 1), and Sevier (n = 1) Counties, Arkansas; Webster Parish, Louisiana (n = 2); and Bowie (n = 1) and Nacogdoches (n = 2) Counties, Texas. Two of 10 (20%) A. opacum from Louisiana harbored an undescribed species of Eimeria. Oocysts of Eimeria trauthi n. sp. were ellipsoidal, 36.6 x 33.1 (33-40 x 29-37) microm, with a thin, single-layered wall; shape index 1.1. Polar granule(s) and micropyle were absent. Oocyst residuum was composed of hundreds of loosely packed homogenous granules of various sizes enclosing a vacuole. Sporocysts were elongate-ellipsoidal, 20.8 x 8.1 (19-22 x 7-9) microm; shape index 2.6. Sporocyst residuum was spherical and composed of a cluster of granules often membrane-bound. This is the first time a coccidium has been reported from an amphibian species in Louisiana and the second time a coccidium has been described from this salamander host. In addition, the following 26 salamanders from various counties in Arkansas, Oklahoma, and Texas were surveyed during the study period and were negative for coccidia: Ambystomatidae, 4 spotted salamanders (Ambystoma maculatum) and 7 mole salamanders (Ambystoma talpoideum); Cryptobranchidae, 4 Ozark hellbenders (Cryptobranchus alleganiensis bishopi); Plethodontidae, 6 spotted dusky salamanders (Desmognathus conanti) and 3 many-ribbed salamanders (Eurycea multiplicata multiplicata); and Salamandridae, 2 central newts (Notophthalmus viridescens louisianensis).

Hamulonema gen. nov. for Teladorsagia hamata and Ostertagia kenyensis in the ostertagiine fauna (Nematoda: Trichostrongyloidea) from African ungulates.

Hamulonema gen. nov. is proposed for Teladorsagia hamata and Ostertagia kenyensis in the ostertagiine nematode fauna found in artiodactyl hosts from Africa. Monomorphic species representing this genus are characterized by a bilaterally symmetrical and parallel synlophe in males and females, a 2-2-1 bursal formula, an accessory bursal membrane that is strongly cuticularized and reduced, a strongly reduced dorsal lobe and ray, and robust spicules with a simple, weakly pointed, ventral process, and curved, hooklike dorsal process. Species referred to Hamulonema nov. gen. are immediately distinguished from those of Camelostrongylus, Longistrongylus, Marshallagia, Orloffia, Ostertagia, and Pseudomarshallagia in which the bursal formula is 2-1-2 in males. Hamulonema nov. gen. is distinguished from those genera having a 2-2-1 bursa, including Africanastrongylus, Cervicaprastrongylus, Hyostrongylus, Mazamastrongylus, Sarwaria, Spiculopteragia, and Teladorsagia by the structure of the synlophe, bursa, genital cone, "0" and "7" papillae, dorsal lobe, and spicules in specific instances. In the global fauna, 4 of 14 ostertagiine genera are endemic to Africa. African genera may represent morphologically divergent and discrete or historically isolated lineages reflecting a pattern of geographic and host colonization as a driver for diversification since the Miocene.

An exploration of diversity among the Ostertagiinae (Nematoda: Trichostrongyloidea) in ungulates from Sub-Saharan Africa with a proposal for a new genus.

Abomasal nematodes (Ostertagiine: Trichostrongyloidea) representing a previously unrecognized genus and species are reported in African buffalo (Syncerus caffer caffer) from Kenya, Uganda, and South Africa. Africanastrongylus buceros gen. nov. et sp. nov. is characterized by a symmetrical tapering synlophe in the cervical region and a maximum of 60 ridges in males and females. Bursal structure is 2-2-1, with subequal Rays 4/5, massive Rays 8, and Rays 9/10, and a massive dorsal lobe that is reduced in length, laterally and dorsally inflated, and positioned ventral to externodorsal rays. Spicules are tripartite, and the gubernaculum is broadly alate in the anterior. A proconus is present. Among ostertagiines with a 2-2-1 bursa (Cervicaprastrongylus, Hyostrongylus, Mazamastrongylus, Sarwaria, Spiculopteragia, and Teladorsagia) specimens of Africanastrongylus are differentiated from respective genera based on the structure of the cervical synlophe, patterns of dorsal, externodorsal, lateral, and ventral rays, and configuration of the genital cone, gubernaculum, and spicules. Among 13 genera of the Ostertagiinae in the global fauna, 3 are entirely limited in distribution to Africa, including Africanastrongylus, Longistrongylus, and Pseudomarshallagia. Another 5 genera including Cervicaprastrongylus, Hyostrongylus, Marshallagia, Ostertagia, and Teladorsagia are represented as mosaics, with diversity centered in Eurasia or the Holarctic. Genera not represented in the African fauna include Camelostrongylus among Caprinae and some Antelopinae from Eurasia, Mazamastrongylus and Spiculopteragia in Cervidae from the Holarctic and Eurasia, respectively, Orloffia in Cervidae and Bovidae from the Holarctic, and Sarwaria among Tragulidae and Bovinae in southern Asia. The diverse nature of the ostertagiine fauna, with a disproportionate number of endemic genera relative to other regions of the northern hemisphere, may reflect the timing of episodic expansion events for artiodactyls into Africa from Eurasia during the Tertiary and Quaternary.