scholarly journals Hiding in the swamp: new capillariid nematode parasitizing New Zealand brown mudfish

2017 ◽  
Vol 92 (3) ◽  
pp. 379-386
Author(s):  
F. Jorge ◽  
R.S.A. White ◽  
R.A. Paterson

AbstractThe extent of New Zealand's freshwater fish-parasite diversity has yet to be fully revealed, with host–parasite relationships still to be described from nearly half the known fish community. While advances in the number of fish species examined and parasite taxa described are being made, some parasite groups, such as nematodes, remain poorly understood. In the present study we combined morphological and molecular analyses to characterize a capillariid nematode found infecting the swim bladder of the brown mudfish Neochanna apoda, an endemic New Zealand fish from peat-swamp-forests. Morphologically, the studied nematodes are distinct from other Capillariinae taxa by the features of the male posterior end, namely the shape of the bursa lobes, and shape of spicule distal end. Male specimens were classified into three different types according to differences in the shape of the bursa lobes at the posterior end, but only one was successfully characterized molecularly. Molecular analysis indicated that the studied capillariid is distinct from other genera. However, inferences about the phylogenetic position of the capillariid reported here will remain uncertain, due to the limited number of Capillariinae taxa characterized molecularly. The discovery of this new capillariid, which atypically infects the swim bladder of its host, which itself inhabits a very unique ecosystem, underlines the very interesting evolutionary history of this parasite, which for now will remain unresolved.

Author(s):  
Sergio A Muñoz-Gómez ◽  
Keira Durnin ◽  
Laura Eme ◽  
Christopher Paight ◽  
Christopher E Lane ◽  
...  

Abstract A most interesting exception within the parasitic Apicomplexa is Nephromyces, an extracellular, probably mutualistic, endosymbiont found living inside molgulid ascidian tunicates (i.e., sea squirts). Even though Nephromyces is now known to be an apicomplexan, many other questions about its nature remain unanswered. To gain further insights into the biology and evolutionary history of this unusual apicomplexan, we aimed to (1) find the precise phylogenetic position of Nephromyces within the Apicomplexa, (2) search for the apicoplast genome of Nephromyces, and (3) infer the major metabolic pathways in the apicoplast of Nephromyces. To do this, we sequenced a metagenome and a metatranscriptome from the molgulid renal sac, the specialized habitat where Nephromyces thrives. Our phylogenetic analyses of conserved nucleus-encoded genes robustly suggest that Nephromyces is a novel lineage sister to the Hematozoa, which comprises both the Haemosporidia (e.g., Plasmodium) and the Piroplasmida (e.g., Babesia and Theileria). Furthermore, a survey of the renal sac metagenome revealed 13 small contigs that closely resemble the genomes of the non-photosynthetic reduced plastids, or apicoplasts, of other apicomplexans. We show that these apicoplast genomes correspond to a diverse set of most closely related but genetically divergent Nephromyces lineages that co-inhabit a single tunicate host. In addition, the apicoplast of Nephromyces appears to have retained all biosynthetic pathways inferred to have been ancestral to parasitic apicomplexans. Our results shed light on the evolutionary history of the only probably mutualistic apicomplexan known, Nephromyces, and provide context for a better understanding of its life style and intricate symbiosis.


2013 ◽  
Vol 67 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Ryota Hayashi ◽  
Benny K.K. Chan ◽  
Noa Simon-Blecher ◽  
Hiromi Watanabe ◽  
Tamar Guy-Haim ◽  
...  

Genome ◽  
2011 ◽  
Vol 54 (12) ◽  
pp. 986-992 ◽  
Author(s):  
Huan Wang ◽  
Dongfa Sun ◽  
Genlou Sun

The phylogeny of diploid Hordeum species has been studied using both chloroplast and nuclear gene sequences. However, the studies of different nuclear datasets of Hordeum species often arrived at similar conclusions, whereas the studies of different chloroplast DNA data generally resulted in inconsistent conclusions. Although the monophyly of the genus is well supported by both morphological and molecular data, the intrageneric phylogeny is still a matter of controversy. To better understand the evolutionary history of Hordeum species, two chloroplast gene loci (trnD-trnT intergenic spacer and rps16 gene) and one nuclear marker (thioreoxin-like gene (HTL)) were used to explore the phylogeny of Hordeum species. Two obviously different types of trnD-trnT sequences were observed, with an approximately 210 base pair difference between these two types: one for American species, another for Eurasian species. The trnD-trnT data generally separated the diploid Hordeum species into Eurasian and American clades, with the exception of Hordeum marinum subsp. gussoneanum. The rps16 data also grouped most American species together and suggested that Hordeum flexuosum has a different plastid type from the remaining American species. The nuclear gene HTL data clearly divided Hordeum species into two clades: the Xu + H genome clade and the Xa + I genome clade. Within clades, H genome species were well separated from the Xu species, and the I genome species were well separated from the Xa genome species. The incongruence between chloroplast and nuclear datasets was found and discussed.


2007 ◽  
Vol 55 (2) ◽  
pp. 73 ◽  
Author(s):  
Amy Driskell ◽  
Les Christidis ◽  
B. J. Gill ◽  
Walter E. Boles ◽  
F. Keith Barker ◽  
...  

The results of phylogenetic analysis of two molecular datasets sampling all three endemic New Zealand ‘honeyeaters’ (Prosthemadera novaeseelandiae, Anthornis melanura and Notiomystis cincta) are reported. The undisputed relatedness of the first two species to other honeyeaters (Meliphagidae), and a close relationship between them, are demonstrated. However, our results confirm that Notiomystis is not a honeyeater, but is instead most closely related to the Callaeidae (New Zealand wattlebirds) represented by Philesturnus carunculatus in our study. An estimated divergence time for Notiomystis and Philesturnus of 33.8 mya (Oligocene) suggests a very long evolutionary history of this clade in New Zealand. As a taxonomic interpretation of these data we place Notiomystis in a new family of its own which takes the name Notiomystidae. We expect this new phylogenetic and taxonomic information to assist policy decisions for the conservation of this rare bird.


2021 ◽  
Author(s):  
Ixchel Gonzalez-Ramirez ◽  
Sergio RS Cevallos-Ferriz ◽  
Carl Rothfels

Premise of study: El Chango is a recently discovered quarry that contains extremely well preserved fossils. The Cenomanian age of the locality corresponds to a time when the global flora was transitioning from gymnosperm- to angiosperm-dominated, yet conifers predominate in this locality. These fossils thus provide a rare opportunity to understand the replacement of conifers by angiosperms as the dominant group of plants. Methods: We collected material from El Chango in annual expeditions (2010 to 2014). We selected the three most abundant and best preserved conifer morphotypes and conducted a total-evidence (i.e., including molecular and morphological data) phylogenetic analysis of a sample of 72 extant conifer species plus the three fossils. We use these results to inform our taxonomic decisions. Results: We obtained four equally most-parsimonious trees (consistency index = 44.1%, retention index = 78.8%). Despite ambiguous relationships among some extant taxa, the three fossil conifers had the same phylogenetic position in all four most parsimonious trees; we describe these species as new: Sequoiadendron helicalancifolium sp. nov. (Cupressaceae), and Microcachrys rhomboidea sp. nov. and Dacrydium bifoliosus sp. nov (Podocarpaceae). The ecosystem is interpreted as a coastal humid mixed forest. Conclusions: Our findings contribute to the understanding of Cenomanian equatorialregions, and support the hypothesis of a geographically and ecologically structured rise of angiosperms, with conifers remaining dominant in brackish-water and angiosperms becoming dominant in freshwater-ecosystems. These fossils fill in gaps in the evolutionary history of lineages like Microcachrys, which we demonstrate occurred in the Northern hemisphere before becoming restricted to its current range (Tasmania).


2014 ◽  
Vol 59 (2) ◽  
Author(s):  
Jacek Dabert

AbstractNeumannella skorackii, a new species of the feather mite family Dermoglyphidae (Acari, Astigmata) is described from the Red-winged Tinamou Rhynchotus rufescens (Temminck, 1815) (Aves, Tinamiformes) from Paraguay and a key to all known species of the genus is provided. The phylogenetic relationships (MP analysis of 25 morphological characters) between Neumannella species along with the evolutionary history of host-parasite associations revealed by Jungle reconciliation method are reconstructed. Relatively low cospeciation contribution to the recent host-parasite associations is discovered.


2018 ◽  
Vol 92 (5) ◽  
pp. 872-882 ◽  
Author(s):  
Tomasz K. Baumiller ◽  
R. Ewan Fordyce

AbstractWe describe a nearly complete, and thus extremely rare, feather star (Crinoidea, Comatulida) from Oligocene strata of North Otago/South Canterbury, New Zealand. A detailed analysis of this specimen, as well as newly recovered material and previously described fragmentary remains from nearby contemporaneous sedimentary units, in addition to relevant historical specimens, lead us to conclude that it cannot be placed in any currently established genus. A new genus,Rautangaroa,is proposed to accommodate it.This intact specimen ofRautangaroa aotearoa(Eagle, 2007), provides rare data on the morphology of arms and cirri. It represents the first example of arm autotomy and regeneration in a fossil feather star and thus has bearing on the importance of predation to the evolutionary history of this group.UUID:http://zoobank.org/c050dafd-93ba-4334-b11b-59209aabb588


2018 ◽  
Vol 5 (6) ◽  
pp. 863-869 ◽  
Author(s):  
Jianni Liu ◽  
Rudy Lerosey-Aubril ◽  
Michael Steiner ◽  
Jason A Dunlop ◽  
Degan Shu ◽  
...  

Abstract The rapid rise of arthropods during the Cambrian quickly established some clades, such as the euarthropod stem-group called Radiodonta, as the dominant and most diverse predators in marine ecosystems. Recent discoveries have shown that the size and dietary ecology of radiodontans are far more diverse than previously thought, but little is known about the feeding habits of juveniles. Here, we document a very small (∼18-mm-long), near-complete specimen of the radiodontan Lyrarapax unguispinus from the early Cambrian Chengjiang Biota of China. This specimen is the smallest radiodontan individual known, representing a juvenile instar. Its adult-like morphology—especially the fully developed spinose frontal appendages and tetraradial oral cone—indicates that L. unguispinus was a well-equipped predator at an early developmental stage, similar to modern raptorial euarthropods, such as mantises, mantis shrimps and arachnids. This evidence, coupled with the basal phylogenetic position of radiodontans, confirms that raptorial feeding habits in juvenile euarthropods appeared early in the evolutionary history of the group.


2019 ◽  
Vol 94 (2) ◽  
pp. 366-377 ◽  
Author(s):  
Bryan M. Gee ◽  
Robert R. Reisz

AbstractNanobamus macrorhinus Schoch and Milner, 2014 is a small amphibamiform temnospondyl from the early Permian Arroyo Formation of Texas. It is most readily characterized by an elongate and partially subdivided naris. This condition is superficially reminiscent of that seen in the coeval trematopids, the group to which N. macrorhinus was originally referred to under an interpretation of the holotype as a larval form. This was discounted by later workers, but the amphibamiform affinities of the specimen were not formalized until recently. The specimen has never been described in the context of its amphibamiform affinities and remains poorly characterized, never having been sampled in a phylogenetic analysis. Here we present a complete, updated osteological description of N. macrorhinus, including an improved characterization of its unique mosaic of plesiomorphic and apomorphic features and clarification of the taxon's autapomorphies. Our analysis of the taxon's phylogenetic position within Amphibamiformes shows that N. macrorhinus was recovered as diverging after basal amphibamiforms, e.g., the micropholids, and before derived amphibamiforms, e.g., the amphibamids. This is supported by the unique mixture of retained plesiomorphies, e.g., nonforeshortened postparietals and an oval choana, and apomorphies, e.g., a narrow interorbital region and slender palatal rami of the pterygoid. These results reflect the complexity of terrestrial amphibamiform diversity and provide further insight into the evolutionary history of the lissamphibian stem in terrestrial environments.


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