28S Locus Research Articles

Morphological and molecular characterization of a novel eimerian species (Apicomplexa: Eimeriidae) from the Australian pelican Pelecanus conspicillatus Temminck, 1824 (Pelecaniformes: Pelecanidae) in Western Australia.

A new Eimeria Schneider, 1875 species is described from an Australian pelican Pelecanus conspicillatus Temminck, 1824 in Western Australia. Sporulated oocysts (n = 23) subspheroidal, 33-35 × 31-33 (34.1 × 32.0) μm; length/width (L/W) ratio 1.0-1.1 (1.07). Wall bi-layered, 1.2-1.5 (1.4) μm thick, outer layer smooth, c.2/3 of total thickness. Micropyle absent, but 2 or 3 polar granules surrounded by a thin membrane, apparently residual, are present. Sporocysts (n = 23) elongate ellipsoidal or capsule shaped, 19-20 × 5-6 (19.5 × 5.6) μm; L/W ratio 3.4-3.8 (3.51). Stieda body vestigial and barely discernible, 0.5 × 1.0 μm; sub-Stieda and para-Stieda bodies absent; sporocyst residuum present, composed of a few dense spherules dispersed among the sporozoites. Sporozoites with robust anterior and posterior refractile bodies and centrally located nucleus. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the cytochrome c oxidase subunit I (COI) gene. At the 18S locus, the new isolate shared 98.6% genetic similarity with Eimeria fulva Farr, 1953 (KP789172), which was identified from a goose in China. At the 28S locus, the new isolate shared the highest similarity of 96.2% with Eimeria hermani Farr, 1953 (MW775031) identified from a whooper-swan (Cygnus cygnus (Linnaeus, 1758)) in China. At the COI gene locus, this new isolate was most closely related to Isospora sp. isolate COI-178 and Eimeria tiliquae [25,26], presented 96.5% and 96.2% genetic similarity, respectively. Based on the morphological and molecular data, this isolate is a new species of coccidian parasite, which is named Eimeria briceae n. sp.

Isospora coronoideae n. sp. (Apicomplexa: Eimeriidae) from the Australian raven (Corvus coronoides) (Passeriformes: Corvidae) (Linnaeus, 1758) in Western Australia.

A new Isospora (Apicomplexa: Eimeriidae) species is described from an Australian raven (Corvus coronoides) in Western Australia. Sporulated oocysts (n = 21) are ovoid, 21.2 (18.4-23.9) μm in length and 18.8 (16.9-20.6) μm in width, with a shape index of 1.13. The bi-layered oocyst wall is smooth and colourless, 1.2μm thick. A polar granule and oocyst residuum is present, but the micropyle is absent. The sporocysts are ovoid-shaped, 16.3 (13.7-18.9) × 10.7 (8.4-12.9) μm, with a shape index (length/width) of 1.52. Stieda and substieda bodies are present, the Stieda body being small and hemidome-shaped and the substieda being indistinct. Each sporocyst with four vermiform sporozoites arranged head to tail. The sporozoites are crescent-shaped, 9.0 (8.9-9.2) × 2.7 (2.3-3.0) μm, with a shape index (length/width) of 3.33. The sporocyst residuum is present. The isolated oocysts had different morphological characteristics when compared with all known Isospora spp. The coccidian parasite was analysed at the 18S and 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) loci. At the 18S locus, I. coronoideae n. sp. exhibited 98.9% similarity to I. neochmiae from a captive-bred red-browed finch (KT224380) and Isospora sp. from domestic pigeons (Columba livia domestica) (AB757860), 98.5% similarity to I. gryphoni (AF080613) from an American goldfinch and 98.3% similarity to I. manorinae (KT224379) from a yellow-throated miner. At the 28S locus, it exhibited 95.4% and 94.8% similarity to I. manorinae (KT224381) and I. anthochaerae (KF766053), respectively. At the COI locus, it exhibited 99.8% and 99.7% similarity to I. butcherae (KY801687) and I. neochmiae (KT224378), respectively. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora coronoideae n. sp. after its host, the Australian raven (Corvus coronoides) (Passeriformes: Corvidae) (Linnaeus, 1758).

Next-generation sequencing reveals two populations of damage-induced small RNAs at endogenous DNA double-strand breaks.

Recent studies suggest that transcription takes place at DNA double-strand breaks (DSBs), that transcripts at DSBs are processed by Drosha and Dicer into damage-induced small RNAs (diRNAs), and that diRNAs are required for DNA repair. However, diRNAs have been mostly detected in reporter constructs or repetitive sequences, and their existence at endogenous loci has been questioned by recent reports. Using the homing endonuclease I-PpoI, we have investigated diRNA production in genetically unperturbed human and mouse cells. I-PpoI is an ideal tool to clarify the requirements for diRNA production because it induces DSBs in different types of loci: the repetitive 28S locus, unique genes and intergenic loci. We show by extensive sequencing that the rDNA locus produces substantial levels of diRNAs, whereas unique genic and intergenic loci do not. Further characterization of diRNAs emerging from the 28S locus reveals the existence of two diRNA subtypes. Surprisingly, Drosha and its partner DGCR8 are dispensable for diRNA production and only one diRNAs subtype depends on Dicer processing. Furthermore, we provide evidence that diRNAs are incorporated into Argonaute. Our findings provide direct evidence for diRNA production at endogenous loci in mammalian cells and give insights into RNA processing at DSBs.

Comprehensive Analysis of the Jellyfish Chrysaora pacifica (Goette, 1886) (Semaeostomeae: Pelagiidae) with Description of the Complete rDNA Sequence.

Jinho Chae, Yoseph Seo, Won Bae Yu, Won Duk Yoon, Hye Eun Lee, Soo-Jung Chang, and Jang-Seu Ki (2018) The Scyphomedusae genus Chrysaora consists of highly diversified jellyfishes. Although morphological systematics of the genus has been documented over the past century, characterization of molecular taxonomy has been attempted only recently. In the present study, we sequenced an 8,167 bp region, encompassing a single ribosomal DNA (rDNA) repeat unit, from Chrysaora pacifica, and used it for phylogenetic analyses. The tandemly repeated rDNA units turned out to consist of both coding and noncoding regions, whose arrangement was found to be the same as that of a typical eukaryote. None of the 5S rRNA sequences were found among the repeat units. Comparative analyses of jellyfish rDNA sequences showed that the 28S locus is highly informative and divergent compared to the 18S locus. Phylogenetic analyses of the 18S and 28S loci revealed that the Semaeostomeae order of jellyfish is separated into taxonomic groups by families and genera, with a few exceptions. The family Pelagiidae was in a clade separate from other groups, thus forming a monophyletic lineage. All Chrysaora included here formed a strongly supported clade within the family Pelagiidae, and Pelagiidae manifested a sister relationship with Cyanea. Nonetheless, Chrysaora was found to be paraphyletic in both 18S and 28S phylogenies. Chrysaora pacifica was clearly distinct from close relatives C. melanaster and C. quinquecirrha. These results provide a special reference for the DNA taxonomy of Pelagiidae jellyfishes in terms of nuclear cistron rDNA sequences and improve our understanding of the molecular phylogenetic relationships among Semaeostomeae jellyfishes.

Morphological and molecular characterisation of Isospora butcherae n. sp. in a silvereye (Zosterops lateralis) (Latham, 1801).

A new Isospora (Apicomplexa:Eimeriidae) species is described from a silvereye (Zosterops lateralis) in Western Australia. Sporulated oocysts of this species are spherical, 24.2 (23.1-25.2) × 23.3 (22.8-23.9) μm, with a shape index (length/width) of 1.02, and with a smooth bi-layered oocyst wall, 1.2μm thick (outer layer 0.9μm, inner 0.3μm). A polar granule is present, but the oocyst residuum and a micropyle are absent. The ovoid-shaped sporocysts are 16.1 (15.7-17.3) × 10.5 (15.7-17.3) μm and have a shape index of 1.53. A hemidome-shaped Stieda and a rectangular-shaped substieda body are present. A sporocyst residuum is present and composed of numerous granules of different sizes scattered among the sporozoites. The oocysts from this isolate are morphologically different from those of all known Isospora spp. This coccidian parasite was molecularly characterised at the 18S, 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) gene. At the 18S locus, based on 1210bp of sequence, this new isolate exhibited 99.9, 99.8, 99.7 and 99.5% similarity to I. sp. MAH-2013a (KF648870) from a superb starling (Lamprotornis superbus) in Canada, I. sp. MS-2003 (AY33157) from a Southern cape sparrow (Plocepasser mahali) in America, I. sp. Tokyo (AB75786) from Japan and I. sp. respectively. Further analysis of a subgroup of 300bp long 18S sequences (n = 11), including I. anthochaerae and the other three Isospora characterised from birds in Western Australia, revealed that I. butcherae n. sp. exhibited 98.3% similarity to both I. sp. MAH-2013a (KF648870) and I. MS-2003 (AY33171). At the 28S locus, this new isolate exhibited 97.3% similarity with I. sp. MS-2003 from a California towhee (Melozone crissalis). At the COI locus, this new isolate exhibited 99.8% similarity to I. neochmiae from a red-browed finch. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora butcherae n. sp. after Mrs. June Butcher for her lifelong dedication as a wildlife rehabilitator. Graphical abstract ᅟ.

Albatrellus roseus sp. nov. (Albatrellaceae; Basidiomycota), the first representative of the genus from Pakistan

Albatrellus roseus sp. nov. is described from Swat, Pakistan, based on morphological and molecular data. Morphological descriptions and illustration for the new species and comparison with closely allied species are provided. Phylogenetic analyses based on nuclear ribosomal DNA (nuc-rDNA) internal transcribed spacer (ITS1-5.8S-ITS2) and 28S loci are studied. This study represent the first record of the genus Albatrellus from Pakistan.

Morphological and molecular characterization of Isospora neochmiae n. sp. in a captive-bred red-browed finch (Neochmia temporalis) (Latham, 1802)

A new Isospora (Apicomplexa: Eimeriidae) species is described from a single red-browed finch (Neochmia temporalis) (subspecies N. temporalis temporalis), that was part of a captive population in Western Australia. Sporulated oocysts of this isolate are spherical, 18.3 (18.2–18.9) × 18.2 (18.2–18.6) μm, with a shape index (length/width) of 1.0; and a smooth and bilayered oocyst wall, 1.2 μm thick (outer layer 0.9 μm, inner 0.3 μm). A polar granule is present, but the oocyst residuum and a micropyle are absent. The sporocysts are ovoid-shaped, 13.3 (9.5–16.4) × 8.6 (6.8–10.0) μm, with a shape index of 1.5. An indistinct Stieda body is present, but the substieda body is absent. A sporocyst residuum is present and composed of numerous granules of different size scattered among the sporozoites. Morphologically, the oocysts from this isolate are different from those of all known valid Isospora spp. Molecular analysis was conducted at 4 loci; the 18S and 28S ribosomal RNA (rRNA), the mitochondrial cytochrome oxidase (COI) gene and the heat shock protein 70 (hsp70) gene. At the 18S locus, this new isolate exhibited 99.9%, 99.8%, 99.7%, and 99.5% similarity to I. sp. MAH-2013a from a superb starling (Lamprotornis superbus), I. MS-2003 from a Southern cape sparrow (Passer melanurus), I. sp. Tokyo from a domestic pigeon (Columba livia domestica) and I. MS-2003 from a Surinam crested oropendula (Psarocolius decumanus). At the 28S locus, this new isolate exhibited 99.7% similarity to both an Isospora sp (MS-2003) from a Northern house sparrow (Passer domesticus) and an Isospora sp. (MS-2003) from a Southern cape sparrow. At the COI locus, this new isolate exhibited 98.9% similarity to an Isospora sp. ex Apodemus flavicollis. At the hsp70 locus, this new isolate exhibited 99% similarity to isolate MS-2003 (AY283879) from a wattled starling (Creatophora cinerea). Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora neochmiae n. sp. after its host, the red-browed finch (Neochmia temporalis).

Morphological and molecular characterization of Eimeria labbeana-like (Apicomplexa:Eimeriidae) in a domestic pigeon (Columba livia domestica, Gmelin, 1789) in Australia

An Eimeria species is described from a domestic pigeon (Columba livia domestica). Sporulated oocysts (n = 35) were subspherical, with a smooth bi-layered oocyst wall (1.0 μm thick). Oocysts measured 20.2 × 16.1 (22.0–18.9 × 15.7–18.9) μm, oocyst length/width (L/W) ratio, 1.38. Oocyst residuum and a polar granule were present. The micropyle was absent. Sporocysts are elongate-ovoid, 13.0 × 6.1 (14.5–12.5 × 5.5–7.0) μm, sporocyst L/W ratio, 2.13 (2.0–2.2), sporocyst residuum was present, composed of numerous granules in a spherical or ovoid mass. Each sporocyst contained 2 banana-shaped sporozoites, 12.3 × 3.5 (11.8–13.0 × 3.3–3.6) μm. A spherical-ellipsoid posterior refractile body was found in the sporozoites. A nucleus was located immediately anterior to the posterior refractile body. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the mitochondrial cytochrome oxidase gene (COI). At the 18S locus, the new isolate shared 98.0% genetic similarity with three Isospora isolates from Japan from the domestic pigeon (Columba livia domestica). At the 28S locus, it grouped separately and shared 92.4% and 92.5% genetic similarity with Isospora anthochaerae (KF766053) from a red wattlebird (Anthochaera carunculata) from Australia and an Isospora sp. (MS-2003 – AY283845) from a Himalayan grey-headed bullfinch (Pyrrhula erythaca) respectively. At COI locus, this new isolate was in a separate clade and shared 95.6% and 90.0% similarity respectively with Eimeria tiliquae n. sp. from a shingleback skink in Australia and an Eimeria sp. from a common pheasant (Phasianus colchicus) from America. Based on the morphological data, this isolate is most similar to Eimeria labbeana. As no molecular data for E. labbeana is available and previous morphological data is incomplete, we refer to the current isolate as E. labbeana-like.

DNA Barcoding of Mealybugs (Hemiptera: Coccoidea: Pseudococcidae) From Mainland China

Mealybugs (Hemiptera: Pseudococcidae) are an insect group that feeds on plant sap; many are major pests of ornamental plants and crops worldwide. The difficulty of morphological identification of mealybugs points to a need for a rapid and effective identification method, like DNA barcoding, to assist morphological taxonomy. Here, we employed diverse methods (best close match [BCM], Neighbor-Joining [NJ] tree, Barcoding with LOGic formulas [BLOG], Poisson Tree Process [PTP] Species Delimitation Method) to test the efficiency of two molecular markers (mitochondrial cytochrome c oxidase I [COI] and large ribosomal subunit gene [28S]) that could be used for species identification of 54 mealybug species that commonly occur in China. Two hundred six COI barcodes (47 species) and 242 28S sequences (53 species) were recovered from 246 individuals. In both the COI and 28S data sets, species except for Planococcus citri and P. minor were unambiguously identified by all the methods. The PTP analysis based on COI sequences generated more putative species in Antonina tesquorum , Atrococcus paludinus , and Formicococcus sp. than morphological identification. Among these three cases, the sequences of At. paludinus showed 3.55% variation at the 28S locus, possibly reflecting cryptic diversity in this taxon. Our study corroborates the utility of the COI and 28S genes in the rapid identification of mealybugs, and the barcode library we provide will create an effective identification system for mealybug pest management in China.

New species of Elaphomyces (Elaphomycetaceae, Eurotiales, Ascomycota) from tropical rainforests of Cameroon and Guyana.

The sequestrate false truffles Elaphomyces favosus, E. iuppitercellus, and E. labyrinthinus spp. nov. are described as new to science from the Dja Biosphere Reserve, Cameroon. Elaphomyces adamizans sp. nov. is described as new from the Pakaraima Mountains of Guyana. The Cameroonian species are the first Elaphomyces taxa to be formally described from Africa, occurring in lowland Guineo-Congolian tropical rainforests dominated by the ectomycorrhizal (ECM) canopy tree Gilbertiodendron dewevrei (Fabaceae subfam. Caesalpinioideae). The Guyanese species is the third to be discovered in lowland tropical South America, occurring in forests dominated by the ECM trees Pakaraimaea dipterocarpacea (Dipterocarpaceae) and Dicymbe jenmanii (Fabaceae subfam. Caesalpinioideae). Macromorphological, micromorphological, habitat, and DNA sequence data are provided for each new species. Molecular and morphological data place these fungi in Elaphomycetaceae (Eurotiales, Ascomycota). Unique morphological features are congruent with molecular delimitation of each of the new species based on a phylogenetic analysis of the rDNA ITS and 28S loci across the Elaphomycetaceae. The phylogenetic analysis also suggests that a common ancestor is shared between some Elaphomyces species from Africa and South America, and that species of the stalked, volvate genus Pseudotulostoma may be nested in Elaphomyces.

Morphological and molecular characterization of Isospora manorinae n. sp. in a yellow-throated miner (Manorina flavigula wayensis) (Gould, 1840)

A new Isospora (Apicomplexa:Eimeriidae) species is described from a single yellow-throated miner bird (Manorina flavigula) (subspecies M. f. wayensis) in Western Australia. Sporulated oocysts (n = 32) of this isolate are spherical to subspherical, 22.8 (20.3–23.8) × 18.3 (17.7–18.7) μm, with a shape index (length/width) of 1.25 (1.2–1.3); and a smooth and bilayered oocyst wall, 1.3 μm thick (outer layer 0.9 μm, inner 0.4 μm). A polar granule is present, but the micropyle and oocyst residuum are absent. The sporocysts are lemon-shaped, 15.5 (14.6–15.8) × 9.5 (9.5–10.2) μm, with a shape index of 1.6. Stieda and substieda bodies are present, the Stieda body being knob-like and the substieda body being subspherical-shaped. A sporocyst residuum is present and composed of numerous granules of different size scattered among the sporozoites, a spheroid or subspheroid refractile body is present in the sporozoite. Morphologically, the oocysts from this isolate are different from those of all known valid Isospora spp. Molecular analysis was conducted at 3 loci; the 18S and 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) gene. At the 18S locus, this new isolate exhibited 99.2% similarity to Isospora gryphoni and three other Isospora spp. Further analysis of a subgroup of 300 bp long 18S sequences (8), including Isospora anthochaerae was conducted. This new isolate grouped in a clade with I. anthochaerae and exhibited 99.3% similarity. At the 28S locus, this new isolate grouped with I. anthochaerae with which it shared 99.1% similarity. At the COI locus, this new isolate exhibited 96.8% similarity to Isospora sp. JCI-2015 from a spectacled warbler (Sylvia conspicillata) in Spain. Further analysis from a subgroup of shorter COI sequences (n = 13) was performed and this new isolate exhibited 99.1% similarity to I. anthochaerae. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora manorinae n. sp. after its host, the yellow-throated miner (Manorina flavigula wayensis).

Isospora serinuse n. sp. (Apicomplexa: Eimeriidae) from a domestic canary (Serinus canaria forma domestica) (Passeriformes: Fringillidae) in Western Australia

A new species, Isospora serinuse n. sp., (Apicomplexa:Eimeriidae) is described from a single domestic canary (Serinus canaria forma domestica) (subspecies S. c. domestica) in Western Australia. Sporulated oocysts of Isospora serinuse n. sp. are spherical or subspherical, 25.5 (24.4–27.0) × 23.5 (22.0–24.8) μm, with a shape index (length/width) of 1.09; and a smooth bilayered oocyst wall, 1.2 μm thick (outer layer 0.9 μm, inner 0.3 μm). A polar granule is present, but a micropyle and oocyst residuum are absent. The sporocysts are lemon-shaped, 18.9 (17.8–20.2) × 11.8 (10.6–13.0) μm, with a shape index of 1.6. Stieda and substieda bodies are present, the Stieda body being a small crescent shape and the substieda being indistinct. Each sporocyst with four vermiform sporozoites arranged head to tail. A sporocyst residuum is present and composed of numerous granules of different sizes that are scattered among the sporozoites. Morphologically, the oocysts of Isospora serinuse n. sp. were different from those of all known valid Isospora spp. Molecular analysis was conducted at 3 loci: the 18S and 28S ribosomal RNA and two separate regions of subunit I of the mitochondrial cytochrome oxidase (COI) gene (designated COIa and COIb). At the 18S locus, Isospora serinuse n. sp. exhibited 97.5% similarity to Isospora sp. Tokyo from a domestic pigeon (Columba livia domestica) in Japan. At the 28S locus, I. serinuse n. sp. exhibited 94.9% similarity to Isospora anthochaerae n. sp. from a red wattlebird (Anthochaera carunculata) in Australia. At the COIa locus, I. serinuse n. sp. exhibited 95.7% similarity to Isospora sospora sp. ex Apodemus flavicollis from a yellow-necked mouse and Isospora gryphoni from an American goldfinch (Carduelis tristis) respectively. At the COIb locus, I. serinuse n. sp. exhibited 96.7% similarity to an Isospora (iSAT4) from a European pied flycatcher (Ficedula hypoleuca). Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora serinuse n. sp. after its host, the domestic canary (S. canaria forma domestica).

Isospora streperae n. sp. (Apicomplexa: Eimeriidae) from a grey currawong (Strepera versicolour plumbea) (Passeriformes: Artamidae) in Western Australia

A new species, Isospora streperae n. sp., (Apicomplexa: Eimeriidae) is described from a single grey currawong bird (Strepera versicolour) (subspecies S. v. plumbea) in Western Australia. Sporulated oocysts (n = 32) are spherical to subspherical, with smooth colourless bilayered oocyst wall, 1.0 µm thick (outer layer 0⋅8 µm, inner 0.2 µm thick). Oocyst with a polar granule, an oocyst residuum and two spheroidal to subspheroidal sporocysts. Oocyst length, 23.8 (20.4–25.0) µm; oocyst width, 22.5 (20.0–24.6) µm; a shape index of 1.06, with Stieda, substieda bodies. Micropyle is absent. Sporocysts with compressed sporocyst residuum and four sporozoites. Sporocyst length, 14.4 (12.5–15.2) µm; sporocyst width, 11.2 (10.6–14.0) µm, sporocyst L/W ratio, 1.29. Necropsy of the bird identified haemorrhaging along the ileum and jejunum, which is where Isospora oocysts were also mostly detected. Molecular analysis was conducted at three loci; the 18S, 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) gene. At the 18S locus, I. streperae n. sp. exhibited 99.5% and 99.4% similarity respectively to an Isospora sp. (MS-2003) from a Southern cape sparrow (Passer melanurus melanurus) and Isospora dovati from a domestic pigeon (Columba livia domestica). At the 28S locus, I. streperae n. sp. exhibited 96.9% similarity to an Isospora sp. (MS-2003) from a grosbeak starling (Scissirostrum dubium) and 95.8% similarity with the Isospora sp. (MS-2003) from a Southern cape sparrow. At the COI locus, I. streperae n. sp. exhibited 95.0% similarity to Isospora sp. from a yellow-necked mouse (Apodemus flavicollis) from the Czech Republic. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora streperae n. sp. after its host, the grey currawong (Strepera versicolour plumbea).

Morphological and molecular characterization of Eimeria paludosa coccidian parasite (Apicomplexa:Eimeriidae) in a dusky moorhen (Gallinula tenebrosa, Gould, 1846) in Australia

An Eimeria species is described from a dusky moorhen (Gallinula tenebrosa). Sporulated oocysts (n = 40) are ovoid, with a pitted single-layered oocyst wall in young oocysts and a relatively smooth wall in the mature oocysts. Oocyst wall was 1.0 µm thick, oocysts measured 17.3 × 13.3 (16.3–17.9 × 12.7–13.9) µm, oocyst length/width (L/W) ratio, 1.3. Oocyst residuum was absent. A large polar granule was always observed in the centre of the micropyle and many small polar granules were observed when the focus was on the wall. Sporocysts are elongate-ovoid, 8.4 × 5.1 (8.0–8.9 × 4.9–5.5) µm, sporocyst L/W ratio, 1.6 (1.5–1.8), sporocyst residuum was present, composed of numerous granules in a spherical or ovoid mass. Each sporocyst contained 2 elongate sporozoites, 7.7 × 2.6 (7–10 × 2.2–3) µm. A spherical-ellipsoid posterior refractile body was found in the sporozoites. A nucleus is located immediately anterior to the posterior refractile body. When the oocyst measurements and features were compared with valid Eimeria species from hosts in the Rallidae family, this Eimeria species was identified as E. paludosa. This is the first report of E. paludosa in Australia and the dusky moorhen (Gallinula tenebrosa) in a new host for this species. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the mitochondrial cytochrome oxidase gene (COI). At the18S locus, E. paludosa shared 97.3% genetic similarity with Eimeria gruis (GenBank accession number: AB544336). It also shared 99.2% genetic similarity with Eimeria crecis (GenBank accession numbers: HE653904 and HE653905) and 98.5% similarity with Eimeria nenei (GenBank accession numbers: HE653906), both of which were identified from a corncrake (Crex crex) in the United Kingdom. At the 28S locus, E. paludosa shared 91.4% similarity with E. papillata from a chicken (Gallus gallus) in the USA. At COI locus, E. paludosa was in a clade by itself and shared 87.2% similarity with E. irresidua, from a European rabbit (Oryctolagus cuniculus) from the Czech Republic. This is the first molecular characterization of E. paludosa.

DNA barcoding in the rust genus Chrysomyxa and its implications for the phylogeny of the genus

Chrysomyxa rusts are fungal pathogens widely present in the boreal forest. Taxonomic delimitation and precise species identification are difficult within this genus because several species display similar morphological features. We applied a DNA barcode system based on the ribosomal internal transcribed spacer region (ITS), large subunit (28S) ribosomal RNA gene, mitochondrial cytochrome oxidase 1 (CO1) and mitochondrial NADH dehydrogenase subunit 6 (NAD6) in 86 strains from 16 different Chrysomyxa species, including members of the Chrysomyxa ledi species complex. The nuclear ITS and 28S loci revealed higher resolving power than the mitochondrial genes. Amplification of the full CO1 barcode region failed due to the presence of introns limiting the dataset obtained with this barcode. In most cases the ITS barcodes were in agreement with taxonomic species based on phenotypic characters. Nevertheless we observed genetically distinct (different DNA barcodes) lineages within Chrysomyxa pyrolae and Chrysomyxa rhododendri, providing some evidence for allopatric speciation within these morphologically defined species. This finding, together with the observed pattern of host specificities of the studied rust fungi, suggest that species diversification within the C. ledi species complex might be governed by a set of factors such as specialisation to certain Ericaceae species as telial hosts and to a lesser extent specialization to different spruce species as aecial hosts. Moreover allopatric speciation by geographic disruption of species also seems to take place. When our data were integrated into a broader phylogenetic framework the Chrysomyxa genus unexpectedly was not resolved as a monophyletic group. Indeed the spruce cone rusts C. pyrolae and C. monesis coalesced with the pine needle rusts belonging to the genus Coleosporium, whereas the microcyclic species Chrysomyxa weirii was embedded within a clade comprising the genus Melampsora.

Molecular Variation and Distribution ofAnopheles fluviatilis(Diptera: Culicidae) Complex in Iran

Anopheles fluviatilis James (Diptera: Culicidae) is one of the known malaria vectors in south and southeastern Iran. Earlier ITS2 sequences analysis of specimens from Iran demonstrated only a single genotype that was identical to species Y in India, which is also the same as species T. We identified 2 haplotypes in the An. fluviatilis populations of Iran based on differences in nucleotide sequences of D3 domain of the 28S locus of ribosomal DNA (rDNA). Comparison of sequence data from 44 Iranian specimens with those publicly available in the Genbank database showed that all of the 28S-D3 sequences from Kazeroun and Khesht regions in Fars Province were identical to the database entry representing species U in India. In other regions, all the individuals showed heterozygosity at the single nucleotide position, which identifies species U and T. It is argued that the 2 species may co-occur in some regions and hybridize; however, the heterozygosity in the 28S-D3 locus was not reflected in ITS2 sequences and this locus for all individuals was identical to species T. This study shows that in a newly diverged species, like members of An. fluviatilis complex, a single molecular marker may not be sufficiently discriminatory to identify all the taxa over a vast geographical area. In addition, other molecular markers may provide more reliable information for species discrimination.

Gene mapping of 28S and 5S rDNA sites in the spined loach Cobitis taenia (Pisces, Cobitidae) from a diploid population and a diploid–tetraploid population

We compare the chromosomal 28S and 5S rDNA patterns of the spined loach C. taenia (2n = 48) from an exclusively diploid population and from a diploid-polyploid population using 28S and 5S rDNA probe preparation and labelling, and fluorescence in situ hybridization (FISH). The 5S rDNA was located in two to three chromosome pairs, and separated from the 28S loci for the males and one female (F1) from the diploid population. Loaches from a diploid-polyploid population, and one female (F2) from the diploid population were characterized by at least one chromosome pair with 5S and 28S overlapping signals. The fishes differed mainly in their number of 28S rDNA loci, located on 3-6 chromosomes. All individuals from both populations were characterized by one acrocentric chromosome bearing a 28S rDNA signal on the telomeres of its long arm. The number of major ribosomal DNA in the karyotype of C. taenia by FISH was always higher than the number of Ag-NORs. Our data confirm the extensive polymorphism of NORs in both populations, as already has been observed in closely related Cobitis species, and less polymorphic 5S rDNA pattern. However, this preliminary result highlights the need for a wider scale study.

A DNA‐sequence based phylogeny for triculine snails (Gastropoda: Pomatiopsidae: Triculinae), intermediate hosts for Schistosoma (Trematoda: Digenea): phylogeography and the origin of Neotricula

AbstractPartial (DNA) sequences were examined for one nuclear (28S rRNA gene) and one mitochondrial (16S rRNA) locus for nine species of pomatiopsid snail (Gastropoda: Rissooidea: Pomatiopsidae) from south‐east Asia and south‐west China. Fresh field samples were collected for the following taxa: Delavaya dianchiensis (Triculinae: Triculini) from Dianchi lake, Yunnan Province, China; Neotricula aperta (Triculinae: Pachydrobiini) from north‐east Thailand; Neotricula burchi from northern Thailand; Oncomelania hupensis robertsoni (Pomatiopsinae: Pomatiopsini) from south‐west China; Tricula bambooensis (Triculinae: Triculini) from Dianchi lake; Tricula bollingi from northern Thailand; Tricula hortensis from Sichuan Province, China; Tricula ludongbini from Dianchi lake; and Tricula xiaolongmenensis from Dianchi lake. This work represents the first published DNA‐sequence data for the Dianchi lake taxa and the first 28S sequence data for all nine taxa. All of these taxa with the exception of N. burchi and the Dianchi taxa transmit Schistosoma in nature; N. aperta and O. h. robertsoni transmit Schistosoma to humans. The data were used to estimate phylogenies using the maximum likelihood method, a Bayesian method, and the maximum parsimony method. The paper aims to examine the relationships between N.aperta, N. burchi and T. bollingi and the relationship between the Chinese taxa and the south‐east Asian taxa; these relationships being important in evaluating certain historical biogeographical hypotheses. Good congruence was found between the phylogenies estimated by the three methods for both the 16S and 28S loci. However, poor congruence was found between the phylogenies based on the 16S and 28S data when the maximum likelihood and Bayesian methods were used. The lack of congruence is explained as a consequence of a rapid, recent, endemic radiation of the Yunnanese Tricula spp.; this hypothesis is consistent with current historical biogeographical models for the Triculinae. The paper puts forward dispersal hypotheses, based on palaeogeographical changes, as possible explanations for the phylogenetic relationships estimated here and for the current biogeography of these taxa.