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1.
Proc Biol Sci ; 290(2010): 20231458, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37909081

RESUMO

Parental care is considered crucial for the enhanced survival of offspring and evolutionary success of many metazoan groups. Most bryozoans incubate their young in brood chambers or intracoelomically. Based on the drastic morphological differences in incubation chambers across members of the order Cheilostomatida (class Gymnolaemata), multiple origins of incubation were predicted in this group. This hypothesis was tested by constructing a molecular phylogeny based on mitogenome data and nuclear rRNA genes 18S and 28S with the most complete sampling of taxa with various incubation devices to date. Ancestral character estimation suggested that distinct types of brood chambers evolved at least 10 times in Cheilostomatida. In Eucratea loricata and Aetea spp. brooding evolved unambiguously from a zygote-spawning ancestral state, as it probably did in Tendra zostericola, Neocheilostomata, and 'Carbasea' indivisa. In two further instances, brooders with different incubation chamber types, skeletal and non-skeletal, formed clades (Scruparia spp., Leiosalpinx australis) and (Catenicula corbulifera (Steginoporella spp. (Labioporella spp., Thalamoporella californica))), each also probably evolved from a zygote-spawning ancestral state. The modular nature of bryozoans probably contributed to the evolution of such a diverse array of embryonic incubation chambers, which included complex constructions made of polymorphic heterozooids, and maternal zooidal invaginations and outgrowths.


Assuntos
Briozoários , Invertebrados , Animais , Filogenia , Reprodução/genética
2.
Mol Phylogenet Evol ; 163: 107262, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34273503

RESUMO

Broad tapeworms (Diphyllobothriidea) are parasites whose adults are capable of infecting a wide range of freshwater, marine and terrestrial tetrapods including humans. Previous works examining the evolution of habitat and host use in this group have been hampered by the lack of a well-resolved phylogeny. In order to produce a robust phylogenetic framework for diphyllobothriideans, we sequenced the complete mitochondrial genome of 13 representatives, carefully chosen to cover the major clades, and two outgroup species representing the Spathebothriidea and Haplobothriidea. In addition, complementary data from the nuclear ribosomal operon was sequenced for 10 representative taxa. Mitogenomes and ssrDNA and lsrDNA were used towards elucidating the phylogenetic framework for the Diphyllobothriidea. The Cephalochlamydidae is confirmed as the earliest diverging diphyllobothriidean lineage, and Solenophoridae and Diphyllobothriidae are sister groups. We infer a probable freshwater origin of the diphyllobothriideans. The ancestral condition for life cycle complexity could not be unambiguously resolved. However, we infer exclusive use of a three-host life cycle following the origin of the Solenophoridae + Diphyllobothriidae. Regarding definitive host use, although we infer reptiles as the most likely ancestral condition, this result should be revisited with a more densely sampled phylogeny in future studies. Freshwater habitat is used by the early diverging lineages within the Solenophoridae + Diphyllobothriidae clade. For the latter, habitat use shifts between freshwater and marine environments, and definitive host use includes marine and terrestrial mammals and birds. We use mitochondrial genomes to distinguish Schistocephalus species occurring in different species of sticklebacks and demonstrate conspecificity of Ligula cf. intestinalis specimens collected from two Fennoscandian ringed seal subspecies.


Assuntos
Cestoides , Genoma Mitocondrial , Animais , Cestoides/genética , Humanos , Óperon , Filogenia
3.
Zoolog Sci ; 37(3): 217-231, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32549536

RESUMO

Viable populations of the cheilostome bryozoan Cribrilina mutabilis Ito, Onishi & Dick exist in the NW Pacific (Russian Far East and northern Japan), NE Atlantic (Scandinavia and Scotland), and NW Atlantic (Maine, USA). The first NE and NW Atlantic records are from Norway (2008) and Casco Bay, Maine, USA (2018), respectively, indicating a relatively recent introduction to the region. Mitochondrial COI gene sequences from North Atlantic populations (Sweden, Norway, and Maine) showed two haplotypes differing by one substitution, but differed from two haplotypes from Akkeshi, northern Japan, by 6-8 substitutions. North Atlantic populations differed morphologically from the Akkeshi population in that some zooids formed a suboral projection, and frontal zooids were more common. While C. mutabilis in northern Japan has been found only on natural or artificial eelgrass (Zostera marina), across its range it has been found on several species of algae, plastic panels and strips, several species of Zostera, and mollusc shells. Similar frequencies of heteromorphic zooids with differing degree of frontal wall calcification, i.e., R (rib)-, I (intermediate)-, and S (shield)-type zooids, in colonies on eelgrass at comparable times of the season and across populations suggest an innate response to seasonal environmental fluctuations, although zooid frequencies were different on non-eelgrass substrates. The increase in trans-Arctic shipping along the Northern Sea Route in recent decades, and previous documentation of C. mutabilis on ship hulls in the Sea of Japan, indicate a clear mechanism for anthropogenic introduction from the Far East to Europe in recent decades.


Assuntos
Distribuição Animal , Briozoários/fisiologia , Espécies Introduzidas , Animais , Briozoários/genética , Complexo IV da Cadeia de Transporte de Elétrons/análise , Genes Mitocondriais , Variação Genética , Haplótipos , Características de História de Vida , Análise de Sequência de DNA
4.
Mar Drugs ; 18(4)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283669

RESUMO

Less than one percent of marine natural products characterized since 1963 have been obtained from the phylum Bryozoa which, therefore, still represents a huge reservoir for the discovery of bioactive metabolites with its ~6000 described species. The current review is designed to highlight how bryozoans use sophisticated chemical defenses against their numerous predators and competitors, and which can be harbored for medicinal uses. This review collates all currently available chemoecological data about bryozoans and lists potential applications/benefits for human health. The core of the current review relates to the potential of bryozoan metabolites in human diseases with particular attention to viral, brain, and parasitic diseases. It additionally weighs the pros and cons of total syntheses of some bryozoan metabolites versus the synthesis of non-natural analogues, and explores the hopes put into the development of biotechnological approaches to provide sustainable amounts of bryozoan metabolites without harming the natural environment.


Assuntos
Produtos Biológicos/farmacologia , Briozoários/química , Briozoários/metabolismo , Animais , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Biologia , Encefalopatias/tratamento farmacológico , Briozoários/classificação , Humanos , Estrutura Molecular , Doenças Parasitárias/tratamento farmacológico , Filogenia , Viroses/tratamento farmacológico
5.
Syst Parasitol ; 97(4): 321-334, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32495189

RESUMO

A new species of deep-sea digenean, Steringophorus merretti n. sp., is described from the bythitid fish Cataetyx laticeps in deep waters of the Goban Spur, Northeastern Atlantic. It is distinguishable from other described members of the genus by its tiny eggs and large cirrus-sac. A phylogenetic tree, based on 28S rDNA sequences, indicates that this species is embedded within a clade of deep-sea species and is sister to the eurybathic species S. thulini Bray & Gibson, 1980. Steringotrema robertpoulini Pérez-Ponce de León, Anglade & Randhawa, 2018 falls within the Steringophorus Odhner, 1905 clade. In view of this the morphological and biological characteristics of species of Steringophorus and Steringotrema are discussed.


Assuntos
Peixes/parasitologia , Trematódeos/classificação , Animais , Oceano Atlântico , Peixes/anatomia & histologia , Peixes/genética , Filogenia , RNA Ribossômico 28S/genética , Especificidade da Espécie
6.
Syst Parasitol ; 97(3): 285-296, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32328809

RESUMO

Chimaeras, or ratfishes, are the only extant group of holocephalan fishes and are the sole host group of gyrocotylidean cestodes, which represent a sister group of the true tapeworms (Eucestoda). These unique, non-segmented cestodes have been known since the 1850s and multiple species and genera have been erected despite a general agreement that the delineation of species on the basis of morphology is effectively impossible. Thus, in the absence of molecular studies, the validity of gyrocotylid taxa and their specific host associations has remained highly speculative. Here we report the presence of Gyrocotyle spp. from rarely-caught deep-sea chimaeras collected in the North-East Atlantic, and describe two new species: G. haffii n. sp. from the bent-nose chimaera, Harriota raleighana Goode & Bean, and G. discoveryi n. sp. from the large-eyed rabbit fish, Hydrolagus mirabilis (Collett). Nuclear ribosomal sequence data were generated for individual parasites taken from different host species collected on different dates and from different localities and were combined with previously published sequences. Phylogenetic analyses supported the recognition of independent lineages and clusters, indicative of species, but were indecisive in recovering the root of the tree in analyses that included non-gyrocotylid outgroup taxa. The molecular data reveal variation not reflected in morphology and point to a complex picture of genetic divergence shaped by both isolation and migration in the deep-sea environment.


Assuntos
Cestoides/classificação , Cestoides/genética , Peixes/parasitologia , Filogenia , Animais , Oceano Atlântico , DNA de Helmintos/genética , Variação Genética , Especificidade da Espécie
7.
BMC Evol Biol ; 19(1): 235, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881939

RESUMO

BACKGROUND: Understanding the phylogenetic relationships among species is one of the main goals of systematic biology. Simultaneously, credible phylogenetic hypotheses are often the first requirement for unveiling the evolutionary history of traits and for modelling macroevolutionary processes. However, many non-model taxa have not yet been sequenced to an extent such that statistically well-supported molecular phylogenies can be constructed for these purposes. Here, we use a genome-skimming approach to extract sequence information for 15 mitochondrial and 2 ribosomal operon genes from the cheilostome bryozoan family, Adeonidae, Busk, 1884, whose current systematics is based purely on morphological traits. The members of the Adeonidae are, like all cheilostome bryozoans, benthic, colonial, marine organisms. Adeonids are also geographically widely-distributed, often locally common, and are sometimes important habitat-builders. RESULTS: We successfully genome-skimmed 35 adeonid colonies representing 6 genera (Adeona, Adeonellopsis, Bracebridgia, Adeonella, Laminopora and Cucullipora). We also contributed 16 new, circularised mitochondrial genomes to the eight previously published for cheilostome bryozoans. Using the aforementioned mitochondrial and ribosomal genes, we inferred the relationships among these 35 samples. Contrary to some previous suggestions, the Adeonidae is a robustly supported monophyletic clade. However, the genera Adeonella and Laminopora are in need of revision: Adeonella is polyphyletic and Laminopora paraphyletically forms a clade with some Adeonella species. Additionally, we assign a sequence clustering identity using cox1 barcoding region of 99% at the species and 83% at the genus level. CONCLUSIONS: We provide sequence data, obtained via genome-skimming, that greatly increases the resolution of the phylogenetic relationships within the adeonids. We present a highly-supported topology based on 17 genes and substantially increase availability of circularised cheilostome mitochondrial genomes, and highlight how we can extend our pipeline to other bryozoans.


Assuntos
Briozoários/classificação , Briozoários/genética , Animais , Evolução Biológica , Evolução Molecular , Genoma Mitocondrial , Filogenia , Análise de Sequência de DNA , Óperon de RNAr
8.
Folia Parasitol (Praha) ; 632016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27189270

RESUMO

Large and small rDNA sequences of 41 species of the family Opecoelidae are utilised to produce phylogenetic inference trees, using brachycladioids and lepocreadioids as outgroups. Sequences were newly generated for 13 species. The resulting Bayesian trees show a monophyletic Opecoelidae. The earliest divergent group is the Stenakrinae, based on two species which are not of the type-genus. The next well-supported clade to diverge is constituted of three species of Helicometra Odhner, 1902. Based on this tree and the characters of the egg and uterus, a new subfamily, the Helicometrinae, is erected and defined to include the genera Helicometra, Helicometrina Linton, 1910 and Neohelicometra Siddiqi et Cable, 1960. The subfamily Opecoelinae is found to be monophyletic, but the Plagioporinae is paraphyletic. The single representative of the Opecoelininae (not of the type genus) is nested within a group of deep-sea 'plagioporines'. The two representatives of the Opistholebetidae are embedded within a group of shallow-water 'plagioporine' species. The Opistholebetidae is reduced to subfamily status pro tem as its morphological and biological characteristics are distinctive. This implies that as opecoelid systematics develops with more molecular evidence, several further subfamilies will be recognised. Many of the morphological characters were found to be homoplasious, but the characters defining the Helicometrinae and Opecoelinae, such as filamented eggs, reduced cirrus-sac and uterine seminal receptacle, are closely correlated with the inferred phylogeny.


Assuntos
Filogenia , Trematódeos/classificação , Animais , Teorema de Bayes , DNA Ribossômico/genética , Feminino , Variação Genética , Trematódeos/anatomia & histologia , Trematódeos/genética
10.
Mol Phylogenet Evol ; 92: 82-107, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26093054

RESUMO

The Macrostomorpha-an early branching and species-rich clade of free-living flatworms-is attracting interest because it contains Macrostomum lignano, a versatile model organism increasingly used in evolutionary, developmental, and molecular biology. We elucidate the macrostomorphan molecular phylogeny inferred from both nuclear (18S and 28S rDNA) and mitochondrial (16S rDNA and COI) marker genes from 40 representatives. Although our phylogeny does not recover the Macrostomorpha as a statistically supported monophyletic grouping, it (i) confirms many taxa previously proposed based on morphological evidence, (ii) permits the first placement of many families and genera, and (iii) reveals a number of unexpected placements. Specifically, Myozona and Bradynectes are outside the three classic families (Macrostomidae, Microstomidae and Dolichomacrostomidae) and the asexually fissioning Myomacrostomum belongs to a new subfamily, the Myozonariinae nov. subfam. (Dolichomacrostomidae), rather than diverging early. While this represents the first evidence for asexuality among the Dolichomacrostomidae, we show that fissioning also occurs in another Myozonariinae, Myozonaria fissipara nov. sp. Together with the placement of the (also fissioning) Microstomidae, namely as the sister taxon of Dolichomacrostomidae, this suggests that fissioning is not basal within the Macrostomorpha, but rather restricted to the new taxon Dolichomicrostomida (Dolichomacrostomidae+Microstomidae). Furthermore, our phylogeny allows new insights into the evolution of the reproductive system, as ancestral state reconstructions reveal convergent evolution of gonads, and male and female genitalia. Finally, the convergent evolution of sperm storage organs in the female genitalia appears to be linked to the widespread occurrence of hypodermic insemination among the Macrostomorpha.


Assuntos
Evolução Biológica , Filogenia , Platelmintos/genética , Platelmintos/fisiologia , Reprodução Assexuada/fisiologia , Animais , Núcleo Celular/genética , DNA Ribossômico/genética , Feminino , Genes Mitocondriais/genética , Masculino , Platelmintos/anatomia & histologia , Platelmintos/classificação , Reprodução Assexuada/genética
11.
Proc Natl Acad Sci U S A ; 108(4): 1490-5, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21220334

RESUMO

Sperm are the most diverse of all animal cell types, and much of the diversity in sperm design is thought to reflect adaptations to the highly variable conditions under which sperm function and compete to achieve fertilization. Recent work has shown that these conditions often evolve rapidly as a consequence of multiple mating, suggesting a role for sexual selection and sexual conflict in the evolution of sperm design. However, very little of the striking diversity in sperm design is understood functionally, particularly in internally fertilizing organisms. We use phylogenetic comparative analyses covering 16 species of the hermaphroditic flatworm genus Macrostomum to show that a complex sperm design is associated with reciprocal mating and that this complexity is lost secondarily when hypodermic insemination--sperm injection through the epidermis--evolves. Specifically, the complex sperm design, which includes stiff lateral bristles, is likely a male persistence trait associated with sexual conflicts over the fate of received ejaculates and linked to female resistance traits, namely an intriguing postcopulatory sucking behavior and a thickened epithelium of the sperm-receiving organ. Our results suggest that the interactions between sperm donor, sperm, and sperm recipient can change drastically when hypodermic insemination evolves, involving convergent evolution of a needle-like copulatory organ, a simpler sperm design, and a simpler female genital morphology. Our study documents that a shift in the mating behavior may alter fundamentally the conditions under which sperm compete and thereby lead to a drastic change in sperm design.


Assuntos
Evolução Biológica , Platelmintos/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Masculino , Dados de Sequência Molecular , Filogenia , Platelmintos/classificação , Platelmintos/genética , Reprodução , Análise de Sequência de DNA , Especificidade da Espécie , Espermatozoides/metabolismo
12.
Folia Parasitol (Praha) ; 61(5): 441-61, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25549500

RESUMO

Morphological examination of novel specimens of paruterinid cestodes from passerine birds from Brazil and Chile and of museum specimens from Paraguay revealed two new species: Anonchotaenia prolixa sp. n. from Elaenia albiceps chilensis Hellmayr from Chile, and Anonchotaenia vaslata sp. n. from Tyrannus melancholicus (Vieillot) (type host) and Myiodynastes maculatus (Statius Muller) from Paraguay. The generic diagnosis of Anonchotaenia Conn, 1900 is amended, prompted by the presence of the armed cirrus and the elongated cirrus sac of A. prolixa. Two species were redescribed: Anonchotaenia brasiliensis Fuhrmann, 1908 from Tachyphonus coronatus (Vieillot) and Thraupis cyanoptera (Vieillot) (new host records) from Brazil, and Thraupis sayaca (Linnaeus) and Volatinia jacarina (Linnaeus) from Paraguay (new host and geographic records); and Anonchotaenia macrocephala Fuhrmann, 1908 from Tachycineta leucorrhoa (Vieillot) (new host record) from Brazil, Tachycineta meyeni (Cabanis) from Chile (new host and geographic record) and Stelgidopteryx ruficollis (Vieillot) from Paraguay (new host and geographic record). Scanning electron microscopy of A. brasiliensis and A. macrocephala revealed less microthrix variation than has been reported for other cyclophyllidean taxa. Sequence data were generated for nuclear ssr- and lsr-DNA and mitochondrial rrnL and cox1 for A. prolixa, A. brasiliensis, and A. macrocephala. Maximum likelihood and Bayesian inference analyses supported each species as distinct, but revealed cryptic diversity among A. brasiliensis specimens from different host families. New host records of A. brasiliensis and A. macrocephala prompted a formal assessment of host specificity. Anonchotaenia prolixa was found to be oioxenous (HS(S) = 0), A. vaslata and A. macrocephala were found to be metastenoxenous (HS(S) = 3.000 and 3.302, respectively), whereas A. brasiliensis was found to be euryxenous (HS(S) = 5.876). Anonchotaenia brasiliensis has been found parasitising several species of different passerine families that participate in mixed-species foraging flocks in the Atlantic Forest. A diversity of species of other families join these flocks and are among the substantial number of South American passerine species yet to be examined for cestodes.


Assuntos
Doenças das Aves/parasitologia , Cestoides/classificação , Cestoides/ultraestrutura , Animais , Doenças das Aves/epidemiologia , Aves , Brasil/epidemiologia , Cestoides/genética , Chile/epidemiologia , Filogenia , Especificidade da Espécie
13.
Syst Parasitol ; 89(1): 15-21, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25079812

RESUMO

A re-examination of published lsrDNA sequence data of haploporid digeneans has shown that the genus Cadenatella Dollfus, 1946, hitherto considered a lepocreadioid, is correctly placed within the superfamily Haploporoidea Nicoll, 1914, although its relationships within the superfamily are not resolved. The morphological similarities and differences between Cadenatella and other haploporoids are discussed, and the subfamily Cadenatellinae Gibson & Bray, 1982 is considered the best repository for Cadenatella spp. at present.


Assuntos
Filogenia , Trematódeos/classificação , Trematódeos/genética , Animais , DNA Ribossômico/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Especificidade da Espécie
14.
J Comp Pathol ; 212: 32-41, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971022

RESUMO

White-tailed antsangies (Brachytarsomys albicauda) are Madagascan rodents uncommonly kept in captivity. Hymenolepis nana is a cestode with an unusual life cycle, incorporating direct, indirect and autoinfective stages. This case series represents the first reported outbreak of H. nana cestodiasis in white-tailed antsangies, summarizing macroscopic and histological findings in four cases. On post-mortem examination (PME), numerous cysticerci were detected consistently throughout the intestinal serosa, liver, mesenteric lymphatic vasculature and mesenteric lymph nodes. Pancreatic cysticerci were observed in one case. Adult tapeworms, larvae and eggs were found only in the small intestine, and faecal egg shedding was a feature. Histopathological examination identified adult, larval and encysted cestodes within the respective gross lesions, with pulmonary, pancreatic and splenic involvement detected in a single case. The cestodes sampled on PME were identified by polymerase chain reaction and DNA sequencing, with H. nana confirmed in all cases. Visceral larva migrans was consistent throughout all specimens, in contrast with the natural infections of standard rodent hosts, and may be considered a likely pathological feature of H. nana infection in white-tailed antsangies.

15.
Ecol Evol ; 14(4): e11276, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38638369

RESUMO

Ctenostomes are a group of gymnolaemate bryozoans with an uncalcified chitinous body wall having few external, skeletal characters. Hence, species identification is challenging and their systematics remain poorly understood, even more so when they exhibit an endolithic (boring) lifestyle. Currently, there are four Recent families of endolithic bryozoans that live inside mineralized substrates like mollusk shells. In particular, Penetrantiidae Silén, 1946 has received considerable attention and its systematic affinity to either cheilostomes or ctenostomes has been debated. Species delimitation of penetrantiids remains difficult, owing to a high degree of colonial and zooidal plasticity. Consequently, an additional molecular approach is essential to unravel the systematics of penetrantiids, their phylogenetic placement and their species diversity. We therefore sequenced the mitochondrial (mt) genomes and two nuclear markers of 27 ctenostome species including nine penetrantiids. Our phylogeny supports the Penetrantiidae as a monophyletic group placed as sister taxon to the remaining ctenostomes alongside paludicellids, arachnidioids and terebriporids. The boring family Terebriporidae d'Orbigny, 1847 were previously considered to be among vesicularioids, but our results suggest an arachnidioid affinity instead. Ctenostome paraphyly is supported by our data, as the cheilostomes nest within them. A Multiporata clade is also well supported, including the former victorelloid genus Sundanella. Altogether, this study provides new insights into ctenostome systematics, assists with species delimitation and contributes to our understanding of the bryozoan tree of life.

16.
Zootaxa ; 3640: 485-99, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26000432

RESUMO

The poorly known proteocephalidean cestode Macrobothriotaenia ficta (Meggitt, 1931) from the sunbeam snake Xenopeltis unicolor (Ophidia: Xenopeltidae) is redescribed on the basis of re-examination of its type specimens from Burma (Myanmar), and vouchers from Thailand and Vietnam. The peculiar morphology of the scolex, which is formed by four pedunculate lobe-bearing pincer-shaped suckers, is described for the first time using scanning electron microscopy. In scolex morphology, M. ficta closely resembles phyllobothriidean cestodes, parasites of elasmobranchs. However, this similarity does not reflect phylogenetic relatedness of these cestodes but instead presents an example of convergent morphological evolution of attachment organs of unrelated groups of cestodes that parasitize different groups of vertebrates. Besides scolex morphology, the genus is characterised by the possession of a very large cirrus-sac, which may reach up to the midline of proglottides, few testes (less than 60), vitelline follicles limited to the dorsal side of proglottides, a large vaginal sphincter, and eggs with a three-layered embryophore covered with rounded projections. Numerous errors in the diagnosis of M. ficta, which appeared in the literature as a result of uncritical compilation of data without examination of original material, are corrected. Multilocus phylogenetic analysis of nuclear ribosomal RNA genes ssr- and lsr-DNA and mitochondrial genes rrnL and cox1 place this species among other snake-parasitizing proteocephalideans of the genus Ophiotaenia. The convergent evolution of scolex morphology across distantly related taxa is discussed.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Serpentes/parasitologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Evolução Biológica , Cestoides/anatomia & histologia , Cestoides/genética , Cestoides/isolamento & purificação , Infecções por Cestoides/parasitologia , Mianmar , Filogenia , Serpentes/classificação , Vietnã
17.
Mol Phylogenet Evol ; 63(3): 834-47, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22406529

RESUMO

The construction of a stable phylogeny for the Cestoda, indicating the interrelationships of recognised orders and other major lineages, has proceeded iteratively since the group first received attention from phylogenetic systematists. Molecular analyses using nuclear ribosomal RNA gene fragments from the small (ssrDNA) and large (lsrDNA) subunits have been used to test competing evolutionary scenarios based on morphological data but could not arbitrate between some key conflicting hypotheses. To the ribosomal data, we have added a contiguous fragment of mitochondrial (mt) genome data (mtDNA) of partial nad1-trnN-trnP-trnI-trnK-nad3-trnS-trnW-cox1-trnT-rrnL-trnC-partial rrnS, spanning 4034-4447 bp, where new data for this region were generated for 18 species. Bayesian analysis of mtDNA and rDNA as nucleotides, and where appropriate as amino acids, demonstrated that these two classes of genes provide complementary signal across the phylogeny. In all analyses, except when using mt amino acids only, the Gyrocotylidea is sister group to all other Cestoda (Nephroposticophora), and Amphilinidea forms the sister group to the Eucestoda. However, an earliest-diverging position of Amphilinidea is strongly supported in the mt amino acid analysis. Amphilinidea exhibit a unique tRNA arrangement (nad1-trnI-trnL2-trnP-trnK-trnV-trnA-trnN-nad3), whereas Gyrocotylidea shares that of the derived lineages, providing additional evidence of the uniqueness of amphilinid genes and genomes. The addition of mtDNA to the rDNA genes supported the Caryophyllidea as the sister group to (Spathebothriidea+remaining Eucestoda), a hypothesis consistently supported by morphology. This relationship suggests a history of step-wise evolutionary transitions from simple monozoic, unsegmented tapeworms to the more familiar polyzoic, externally segmented (strobilate) forms. All our data partitions recovered Haplobothriidea as the sister group to Diphyllobothriidae. The sister-group relationship between Diphyllidea and Trypanorhyncha, as previously established using rDNA, is not supported by the mt data, although it is supported by the combined mt and rDNA analysis. With regards to the more derived taxa, in all except the mt amino acid analysis, the following topology is supported: (Bothriocephalidea (Litobothriidea (Lecanicephalidea (Rhinebothriidea (Tetraphyllidea, (Acanthobothrium, Proteocephalidea), (Nippotaeniidea, Mesocestoididae, Tetrabothriidea, Cyclophyllidea)))))), where the Tetraphyllidea are paraphyletic. Evidence from the mt data provides strong (nucleotides) to moderate (amino acids) support for Tetraphyllidea forming a group to the inclusion of Proteocephalidea, with the latter consistently forming the sister group to Acanthobothrium. The interrelationships among Nippotaeniidea, Mesocestoididae, Tetrabothriidea and Cyclophyllidea remain ambiguous and require further systematic attention. Mitochondrial and nuclear rDNA data provide conflicting signal for certain parts of the cestode tree. In some cases mt data offer results in line with morphological evidence, such as the interrelationships of the early divergent lineages. Also, Tetraphyllidea, although remaining paraphyletic with the inclusion of the Proteocephalidea, does not include the most derived cestodes; a result which has consistently been obtained with rDNA.


Assuntos
Cestoides/genética , DNA Mitocondrial/genética , Animais , Teorema de Bayes , Cestoides/anatomia & histologia , Cestoides/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Helminto/genética , Modelos Genéticos , Anotação de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , RNA de Helmintos/genética , RNA Ribossômico/genética
18.
Mol Phylogenet Evol ; 62(2): 718-35, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22126903

RESUMO

We present the most comprehensive molecular phylogeny of bryozoans to date. Our concatenated alignment of two nuclear ribosomal and five mitochondrial genes includes 95 taxa and 13,292 nucleotide sites, of which 8297 were included. The number of new sequences generated during this project are for each gene:ssrDNA (32), lsrDNA (22), rrnL (38), rrnS (35), cox1 (37), cox3 (34), and cytb (44). Our multi-gene analysis provides a largely stable topology across the phylum. The major groups were unambiguously resolved as (Phylactolaemata (Cyclostomata (Ctenostomata, Cheilostomata))), with Ctenostomata paraphyletic. Within Phylactolaemata, (Stephanellidae, Lophopodidae) form the earliest divergent clade. Fredericellidae is not resolved as a monophyletic family and forms a clade together with Plumatellidae, Cristatellidae and Pectinatellidae, with the latter two as sister taxa. Hyalinella and Gelatinella nest within the genus Plumatella. Cyclostome taxa fall into three major clades: i. (Favosipora (Plagioecia, Rectangulata)); ii. (Entalophoroecia ((Diplosolen, Cardioecia) (Frondipora, Cancellata))); and iii. (Articulata ((Annectocyma, Heteroporidae) (Tubulipora (Tennysonia, Idmidronea)))), with suborders Tubuliporina and Cerioporina, and family Plagioeciidae each being polyphyletic. Ctenostomata is composed of three paraphyletic clades to the inclusion of Cheilostomata: ((Alcyonidium, Flustrellidra) (Paludicella (Anguinella, Triticella)) (Hislopia (Bowerbankia, Amathia)) Cheilostomata); Flustrellidra nests within the genus Alcyonidium, and Amathia nests within the genus Bowerbankia. Suborders Carnosa and Stolonifera are not monophyletic. Within the cheilostomes, Malacostega is paraphyletic to the inclusion of all other cheilostomes. Conopeum is the most early divergent cheilostome, forming the sister group to ((Malacostega, Scrupariina, Inovicellina) ((Hippothoomorpha, Flustrina) (Lepraliomorpha, Umbonulomorpha))); Flustrina is paraphyletic to the inclusion of the hippothoomorphs; neither Lepraliomorpha nor Umbonulomorpha is monophyletic. Ascophorans are polyphyletic, with hippothoomorphs grouping separately from lepraliomorphs and umbonulomorphs; no cribrimorphs were included in the analysis. Results are discussed in the light of molecular and morphological evidence. Ancestral state reconstruction of larval strategy in Gymnolaemata revealed planktotrophy and lecithotrophy as equally parsimonious solutions for the ancestral condition. More comprehensive taxon sampling is expected to clarify this result. We discuss the extent of non-bryozoan contaminant sequences deposited in GenBank and their impact on the reconstruction of metazoan phylogenies and those of bryozoan interrelationships.


Assuntos
Briozoários/genética , Evolução Molecular , Genes Mitocondriais , Especiação Genética , Filogenia , Algoritmos , Animais , Sequência de Bases , Teorema de Bayes , Briozoários/classificação , Primers do DNA , Bases de Dados Genéticas , Larva/classificação , Larva/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
19.
Mol Biol Rep ; 39(9): 8601-14, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22714911

RESUMO

The bryozoan Celleporella has been shown to be composed of multiple, often cryptic, lineages. We sequenced two complete mitochondrial (mt) genomes of the Celleporella hyalina species complex from Wales, UK and Norway (i) to determine genetic divergence at the complete mt genome level, and (ii) to design new molecular markers for examining the interrelationships amongst the major lineages. In addressing (i), we estimated genetic divergence at three levels: (a) nucleotide diversity (π), (b) genome size, and (c) gene order. Genes nad4L, nad6, and atp8 showed the highest levels of divergence, and rrnL, rrnS, and cox1 showed the lowest levels. Inter-genome nucleotide divergence of protein-coding and ribosomal RNA genes, measured as π, was 0.21. The two genomes differed substantially in size, with the Norwegian genome being 2,573 base pairs (bp) longer than the Welsh genome, 17,265 and 14,692 bp, respectively. This difference in size is attributable to long non-coding regions present in the Norwegian genome. Both genomes exhibit similar gene orders, except for the translocation of one transfer RNA (trnA). Considering the high nucleotide diversity, genome size difference and change in gene order, these mt genomes are considered sufficiently divergent to have originated from two distinct species. In addressing (ii) we designed PCR primers that flank the most conserved regions of the genome: 1,300 bp of cox1 and a contiguous 2,000 bp fragment of rrnL + rrnS. The primers have yielded products for tissue from Wales, Norway, New Zealand, Alaska and Chile and should provide useful tools in establishing species- and population-level diversity within the Celleporella complex.


Assuntos
Briozoários/genética , Genoma Mitocondrial , Animais , Composição de Bases , Briozoários/classificação , Briozoários/ultraestrutura , Códon de Iniciação , Códon de Terminação , Feminino , Ordem dos Genes , Marcadores Genéticos , Masculino , Conformação de Ácido Nucleico , Filogenia , RNA de Transferência/química
20.
Parasitol Int ; 88: 102538, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35007763

RESUMO

A new species of proteocephalid cestodes, provisionally assigned to the polyphyletic genus Ophiotaenia La Rue, 1911 (Cestoda: Proteocephalidae), is described from Compsophis infralineatus (Günther) (Serpentes: Pseudoxyrhophiidae) endemic to Madagascar. Ophiotaenia oreae n. sp. differs from all African and Asian species of Ophiotaenia by possessing more uterine diverticula (68-82 on one side). It is also characterised by the absence of an apical organ, the relative sizes of the cirrus-sac and ovary, the almost equatorial position of the gonopore, the diameter of the embryophore, and other biometric characteristics. Phylogenetic relationships of the new species indicate its relatedness to Indomalayan and Australasian proteocephalids from reptiles. Ophiotaenia oreae n. sp. formed a well-supported clade composed of species of Australophiotaenia de Chambrier, Beveridge and Scholz, 2018 from Australian snakes, Macrobothriotaenia ficta (Meggitt, 1931) from Xenopeltis unicolor Reinwardt in Boie from Vietnam, Ophiotaenia sp. from Trimeresurus flavomaculatus (Gray) from the Philippines, and Ophiotaenia bungari de Chambrier, Binh and Scholz, 2012 from Bungarus fasciatus (Schneider) from Vietnam. The only proteocephalid from Madagascan snakes sequenced so far, Ophiotaenia lapata Rambeloson, Ranaivoson and de Chambrier, 2012 from Madagascarophis colubrinus (Schlegel), does not form a monophyletic group with the new species. The actual species diversity of reptilian cestodes in Madagascar is undoubtedly underestimated. Because of the assumed strict (oioxenous) host specificity of reptilian proteocephalids and rich fauna of snakes occurring in Madagascar, it is plausible to expect the existence of dozens new species of proteocephalids on this island.


Assuntos
Cestoides , Parasitos , Animais , Austrália , Cestoides/genética , Feminino , Madagáscar/epidemiologia , Filogenia , Serpentes/parasitologia
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