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1.
Ecol Appl ; 31(7): e02416, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34278627

RESUMEN

Rapid environmental change is reshaping ecosystems and driving species loss globally. Carnivore populations have declined and retracted rapidly and have been the target of numerous translocation projects. Success, however, is complicated when these efforts occur in novel ecosystems. Identifying refuges, locations that are resistant to environmental change, within a translocation framework should improve population recovery and persistence. American martens (Martes americana) are the most frequently translocated carnivore in North America. As elsewhere, martens were extirpated across much of the Great Lakes region by the 1930s and, despite multiple translocations beginning in the 1950s, martens remain of regional conservation concern. Surprisingly, martens were rediscovered in 2014 on the Apostle Islands of Lake Superior after a putative absence of >40 yr. To identify the source of martens to the islands and understand connectivity of the reintroduction network, we collected genetic data on martens from the archipelago and from all regional reintroduction sites. In total, we genotyped 483 individual martens, 43 of which inhabited the Apostle Islands (densities 0.42-1.46 km-2 ). Coalescent analyses supported the contemporary recolonization of the Apostle Islands with progenitors likely originating from Michigan, which were sourced from Ontario. We also identified movements by a first-order relative between the Apostle Islands and the recovery network. We detected some regional gene flow, but in an unexpected direction: individuals moving from the islands to the mainland. Our findings suggest that the Apostle Islands were naturally recolonized by progeny of translocated individuals and now act as a source back to the reintroduction sites on the mainland. We suggest that the Apostle Islands, given its protection from disturbance, complex forest structure, and reduced carnivore competition, will act as a potential refuge for marten along their trailing range boundary and a central node for regional recovery. Our work reveals that translocations, even those occurring along southern range boundaries, can create recovery networks that function like natural metapopulations. Identifying refuges, locations that are resistant to environmental change, within these recovery networks can further improve species recovery, even within novel environments. Future translocation planning should a priori identify potential refuges and sources to improve short-term recovery and long-term persistence.


Asunto(s)
Ecosistema , Mustelidae , Animales , Bosques , Flujo Génico , Genotipo , Humanos
2.
J Evol Biol ; 32(6): 580-591, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30860304

RESUMEN

Major habitat transitions, such as those from marine to freshwater habitats or from aquatic to terrestrial habitats, have occurred infrequently in animal evolution and may represent a barrier to diversification. Identifying genomic events associated with these transitions can help us better understand mechanisms that allow animals to cross these barriers and diversify in new habitats. Study of the Capitella telata and Helobdella robusta genomes allows examination of one such habitat transition (marine to freshwater) in Annelida. Initial examination of these genomes indicated that the freshwater leech H. robusta contains many more copies (12) of the sodium-potassium pump alpha-subunit (Na+ /K+ -ATPase) gene than does the marine polychaete C. telata (2). The sodium-potassium pump plays a key role in maintenance of cellular ionic balance and osmoregulation, and Na+ /K+ -ATPase duplications may have helped annelids invade and diversify in freshwater habitats. To assess whether the timing of Na+ /K+ -ATPase duplications coincided with the marine-to-freshwater transition in Clitellata, we used transcriptomic data from 18 annelid taxa, along with the two genomes, to infer a species phylogeny and identified Na+ /K+ -ATPase gene transcripts in order to infer the timing of gene duplication events using tree-based methods. The inferred timing of Na+ /K+ -ATPase duplication events is consistent with the timing of the initial marine-to-freshwater transition early in the history of clitellate annelids, supporting the hypothesis that gene duplications may have played a role in the annelid diversification into freshwater habitats.


Asunto(s)
Duplicación de Gen , Sanguijuelas/genética , Filogenia , ATPasa Intercambiadora de Sodio-Potasio/genética , Animales , Ecosistema , Genoma , Familia de Multigenes
3.
BMC Evol Biol ; 17(1): 123, 2017 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-28558722

RESUMEN

BACKGROUND: Earthworms (Crassiclitellata) are a diverse group of annelids of substantial ecological and economic importance. Earthworms are primarily terrestrial infaunal animals, and as such are probably rather poor natural dispersers. Therefore, the near global distribution of earthworms reflects an old and likely complex evolutionary history. Despite a long-standing interest in Crassiclitellata, relationships among and within major clades remain unresolved. METHODS: In this study, we evaluate crassiclitellate phylogenetic relationships using 38 new transcriptomes in combination with publicly available transcriptome data. Our data include representatives of nearly all extant earthworm families and a representative of Moniligastridae, another terrestrial annelid group thought to be closely related to Crassiclitellata. We use a series of differentially filtered data matrices and analyses to examine the effects of data partitioning, missing data, compositional and branch-length heterogeneity, and outgroup inclusion. RESULTS AND DISCUSSION: We recover a consistent, strongly supported ingroup topology irrespective of differences in methodology. The topology supports two major earthworm clades, each of which consists of a Northern Hemisphere subclade and a Southern Hemisphere subclade. Divergence time analysis results are concordant with the hypothesis that these north-south splits are the result of the breakup of the supercontinent Pangaea. CONCLUSIONS: These results support several recently proposed revisions to the classical understanding of earthworm phylogeny, reveal two major clades that seem to reflect Pangaean distributions, and raise new questions about earthworm evolutionary relationships.


Asunto(s)
Oligoquetos/clasificación , Oligoquetos/genética , Suelo , Animales , Evolución Biológica , Filogenia
4.
Mol Phylogenet Evol ; 66(1): 30-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22995849

RESUMEN

Branchiobdellidans, or crayfish worms, are ectosymbiotic clitellate annelids associated primarily with freshwater crayfishes. The main objectives of our study were to infer a molecular phylogeny for the North American Branchiobdellida, examine its congruence with morphology-based hypotheses of relationships at the subfamily and genus level, and use our dataset to assess consistency of GenBank-archived branchiobdellidan sequences. We used nucleotide sequence data from two mtDNA genes (COI and 16S rDNA) and three nuclear genes (28S rDNA, 18S rDNA, and ITS1) to estimate phylogenetic relationships among 47 described and one undescribed species of Branchiobdellida. We recovered a monophyletic branchiobdellidan clade with generally short branch lengths, suggesting that a large portion of the taxon has likely undergone a recent and rapid radiation in North America. Results from our phylogenetic analyses indicate that current taxonomic groupings are largely unsupported by the molecular data. All four subfamilies are either paraphyletic or polyphyletic, and only three of seven sampled non-monotypic genera were monophyletic. We found a high rate (49%) of inconsistency in GenBank-archived sequences, over 70% of which can be attributed to field- or laboratory-based error.


Asunto(s)
Anélidos/clasificación , Evolución Molecular , Filogenia , Animales , Anélidos/genética , Teorema de Bayes , Núcleo Celular/genética , ADN Mitocondrial/genética , ADN Espaciador Ribosómico/genética , América del Norte , ARN Ribosómico 16S/genética , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Análisis de Secuencia de ADN
5.
Zootaxa ; 5270(2): 207-230, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37518167

RESUMEN

Two new species of stream-dwelling crayfish, Cambarus lapidosus, the Stony Fork Crayfish, and Cambarus burchfielae, the Falls Crayfish, are described from the Yadkin River basin in western North Carolina, USA, using an integrative taxonomic approach consisting of morphological, genetic, and biogeographic data. Both species were previously considered to be members of the widely distributed Cambarus species C complex, which occurs throughout mid-Atlantic Slope river basins; however, they are in fact morphologically and genetically more similar to the Cambarus robustus species complex from interior basins in the south-central Appalachians, indicating Atlantic basin stream capture of an Interior basin faunal group has occurred in this region. Both new species described herein can be differentiated from these two complexes, and each other, by several morphological characteristics. Cambarus lapidosus and C. burchfielae are differentiated from C. species C by the absence of cervical spines and the presence of 1-2 subpalmar tubercles on the chelae in most specimens; both species are less-punctate across the areola than C. aff. robustus. Cambarus burchfielae is further differentiated from C. lapidosus, C. species C, and C. aff. robustus by the presence of a narrower and sparsely punctate areola, a single weak row of tubercles on the mesial margin of the palm, and the absence of tubercles on the dorsal surface of the dactyl. The newly described species are genetically sister taxa and together are most similar by genetic distance to undescribed members of the C. robustus species complex from the nearby (~30 km) Watauga River basin and most phylogenetically similar to C. aff. robustus from the adjacent New River basin; both are interior basin drainages. The newly-described species are endemic to the Blue Ridge Mountains of western North Carolina and have restricted distributions (<100 km2-150 km2) in small (<4th order) tributaries to the Yadkin River. Cambarus lapidosus is known only from the upper Stony Fork watershed and C. burchfielae is known only from the upper reaches of the adjacent Lewis Fork watershed; both species likely qualify for conservation status protections under narrow geographic range criteria.


Asunto(s)
Astacoidea , Ríos , Animales , North Carolina , Astacoidea/genética , Distribución Animal
6.
Zootaxa ; 5270(3): 437-470, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37518155

RESUMEN

Isoperla riverae sp. n. is described from the southeastern USA. The new species is proposed based on details of the adult habitus, male aedeagus, vesicle, female subgenital plate, ovum chorion, and larval habitus. Supporting data includes color images, scanning electron micrographs, genetic analysis of DNA barcodes, and comparative morphology of cognate species. The larva of Isoperla lenati Szczytko & Kondratieff, 2015 is also described supported by color images.


Asunto(s)
Insectos , Simpatría , Femenino , Masculino , Animales , Larva , Neoptera , Corion
8.
Zootaxa ; 5082(4): 322-340, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-35390961

RESUMEN

The Cataloochee Crayfish, Cambarus ectopistes sp. nov., is a large, stream-dwelling crayfish that occupies a narrow noncontiguous distribution within the Appalachian Mountain region running through the Upper Tennessee River basin, in the French Broad, Pigeon, and Nolichucky watersheds along the Tennessee and North Carolina border. It is split from the southernmost extent of the C. robustus species complex, and is morphologically and genetically most similar to a second undescribed member of the group endemic to the upper Nolichucky River watershed in North Carolina. Cambarus ectopistes sp. nov. can be distinguished from other members of the C. robustus complex and co-distributed congeners by a combination of characters, including body size, coloration, and morphology of the chela and rostrum. The new species is typically found in channel and edge habitats of moderate to large perennial streams with large cobbles and boulders.


Asunto(s)
Astacoidea , Ríos , Distribución Animal , Animales , Astacoidea/anatomía & histología , Columbidae , North Carolina , Tennessee
9.
Mol Ecol ; 19(2): 227-40, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20041991

RESUMEN

Reintroductions and translocations are increasingly used to repatriate or increase probabilities of persistence for animal and plant species. Genetic and demographic characteristics of founding individuals and suitability of habitat at release sites are commonly believed to affect the success of these conservation programs. Genetic divergence among multiple source populations of American martens (Martes americana) and well documented introduction histories permitted analyses of post-introduction dispersion from release sites and development of genetic clusters in the Upper Peninsula (UP) of Michigan <50 years following release. Location and size of spatial genetic clusters and measures of individual-based autocorrelation were inferred using 11 microsatellite loci. We identified three genetic clusters in geographic proximity to original release locations. Estimated distances of effective gene flow based on spatial autocorrelation varied greatly among genetic clusters (30-90 km). Spatial contiguity of genetic clusters has been largely maintained with evidence for admixture primarily in localized regions, suggesting recent contact or locally retarded rates of gene flow. Data provide guidance for future studies of the effects of permeabilities of different land-cover and land-use features to dispersal and of other biotic and environmental factors that may contribute to the colonization process and development of spatial genetic associations.


Asunto(s)
Flujo Génico , Genética de Población , Mustelidae/genética , Animales , Análisis por Conglomerados , Conservación de los Recursos Naturales , Desequilibrio de Ligamiento , Michigan , Repeticiones de Microsatélite , Modelos Genéticos , Dinámica Poblacional , Análisis de Secuencia de ADN
10.
Zootaxa ; 4565(2): zootaxa.4565.2.10, 2019 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-31716483

RESUMEN

Entocythere cambaria was described by William S. Marshall in 1903 as the first species in what would later become family Entocytheridae. Designated as the type species of Entocythere both by original designation and monotypy, E. cambaria is integral to understanding relationships within the genus. Yet, a type series for E. cambaria was not designated, and specimens used by Marshall to describe the species have since been deemed no longer extant. C.W. Hart Jr. and Dabney Hart assigned a neotype for E. cambaria in 1974, but this specimen was not catalogued into the Invertebrate Zoology Collection at the Smithsonian Institution's National Museum of Natural History, and subsequently disappeared. A specimen, which we believe to be Hart and Hart's intended neotype, was recently discovered, giving us the opportunity to clarify the neotype designation of E. cambaria, and provide a complete description based on modern standards for podocopid ostracods. In addition, based on careful scrutiny of numerous specimens, including the types, we synonymize Entocythere illinoisensis with E. cambaria, and describe in full for the time the adult female of the species.


Asunto(s)
Crustáceos , Animales , Femenino , Museos
11.
Zootaxa ; 4568(3): zootaxa.4568.3.6, 2019 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-31715847

RESUMEN

A new species of stream-dwelling crayfish, Cambarus franklini, the South Mountains crayfish, is described from the upper South Fork Catawba River basin in western North Carolina, USA using morphological and genetic data. Cambarus franklini was previously considered a member of the widespread and morphologically variable Cambarus species C complex and is morphologically most similar to an undiagnosed member of the group native to the upper Catawba River basin in NC. Cambarus franklini can be differentiated from this species group by several morphological characteristics including: lacking a well-defined double row of tubercles along the mesial margin of the palm, possessing a more weakly convergent and longer acumen, and conspicuous blue-green and red coloration, particularly throughout the telson and along the distal margins of the rami. This species is phylogenetically most similar to Cambarus johni, Cooper, 2006, another former member of the Cambarus species C group. Cambarus franklini has a limited geographic range (100 km2) and is currently known only from the Henry and Jacob Fork watersheds in the South Mountains region of the Eastern Blue Ridge foothills.


Asunto(s)
Astacoidea , Ríos , Distribución Animal , Animales , Color , North Carolina
12.
Zootaxa ; 4683(3): zootaxa.4683.3.3, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31715917

RESUMEN

The Jewel Mudbug, Lacunicambarus dalyae sp. nov., is a large, colorful primary burrowing crayfish found in Alabama, Florida, Georgia, Mississippi and Tennessee. This species is most similar in appearance to the Paintedhand Mudbug, L. polychromatus, a species found across the Midwestern United States. The ranges of the two species overlap minimally, and they can be distinguished from each other based on several characters, the most notable of which is the much longer central projection of the gonopod in Form I and II males of L. dalyae sp. nov. relative to L. polychromatus. Like its congeners, L. dalyae sp. nov. is commonly found in burrows in the banks and floodplains of streams and is resilient to a moderate amount of anthropogenic habitat degradation, being occasionally collected from burrows in roadside ditches and urban lawns.


Asunto(s)
Astacoidea , Animales , Masculino , Sudeste de Estados Unidos
13.
Zootaxa ; 4560(1): 40-50, 2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30790990

RESUMEN

Cambarus acuminatus was described by Walter Faxon in 1884 from three specimens collected from the Saluda River in northwestern South Carolina, USA. Cambarus acuminatus sensu lato has since been acknowledged to comprise a species complex. This complex, also known as Cambarus sp. C, spans a range across much of the Piedmont Plateau and Coastal Plain from central South Carolina north to Maryland and southeastern Pennsylvania. A primary impediment to a much-needed thorough taxonomic assessment and revision of C. sp. C is the absence of taxonomically useful type material of C. acuminatus coupled with the lack of a detailed description of the species. Here we provide a redescription of C. acuminatus based on modern standards for astacoidean crayfishes in the genus Cambarus and emend the circumscription of the species, thereby laying the groundwork necessary for future taxonomic and phylogenetic work within, and involving, the C. sp. C complex.


Asunto(s)
Astacoidea , Distribución Animal , Animales , Maryland , Filogenia , South Carolina
14.
Genome Biol Evol ; 11(11): 3082-3093, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31214691

RESUMEN

Leeches (Hirudinida) comprise a charismatic, yet often maligned group of organisms. Despite their ecological, economic, and medical importance, a general consensus on the phylogenetic relationships of major hirudinidan lineages is lacking. This absence of a consistent, robust phylogeny of early-diverging lineages has hindered our understanding of the underlying processes that enabled evolutionary diversification of this clade. Here, we used an anchored hybrid enrichment-based phylogenomic approach, capturing hundreds of loci to investigate phylogenetic relationships among major hirudinidan lineages and their closest living relatives. Our results suggest that a dramatic reinterpretation of early leech evolution is warranted. We recovered Branchiobdellida as sister to a clade that includes all major lineages of hirudinidans, but found Acanthobdella to be nested within Oceanobdelliformes. These results cast doubt on the utility of Acanthobdella as a "missing link" used to explain the origin of blood-feeding in hirudineans. Further, our results support a deep divergence between predominantly marine and freshwater lineages, while not supporting the reciprocal monophyly of jawed and proboscis-bearing leeches. To sum up, our phylogenomic resolution of early-diverging leeches provides a necessary foundation for illuminating the evolution of host-symbiont associations and key adaptations that have allowed leeches to colonize a wide diversity of habitats worldwide.


Asunto(s)
Sanguijuelas/genética , Animales , Filogenia , Análisis de Secuencia de ADN , Simbiosis/genética , Simbiosis/fisiología
15.
Zootaxa ; 4448(1): 1-129, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30313866

RESUMEN

Ostracods of the family Entocytheridae are obligate ectosymbionts of other crustaceans, including crayfishes, isopods, amphipods, and a species of freshwater crab. Entocytheridae, with five subfamilies, 35 genera, and 213 currently accepted species, represents one the most diverse groups of extant freshwater ostracods. Here, we present the results of an extensive literature review, documenting the often complex historical taxonomic activity and resulting classification of Entocytheridae. This overview highlights inconsistencies, errors, and additional sources of confusion that have been inadvertently introduced into the literature, a number of which have remained uncorrected for decades. Also provided is a comprehensive checklist of taxonomic nomenclature and a list of currently accepted names in Entocytheridae.


Asunto(s)
Astacoidea , Crustáceos , Anfípodos , Animales , Agua Dulce , Isópodos
16.
Zootaxa ; 4403(1): 171-185, 2018 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-29690251

RESUMEN

Cambarus polypilosus sp. nov. is a stream-dwelling crayfish endemic to tributaries in the Buffalo and lower Duck River drainage, and a reach of the lower Tennessee River in the Western Highland Rim of West-Central Tennessee, U.S.A. The new species is closely allied to the three members of the former subgenus Glareocola, but can be differentiated from each by a combination of characters, including body size, coloration, spination, setation, and form I male gonopod morphology. Several meristic measurements and ratios also differentiate C. polypilosus sp. nov. from Cambarus friaufi, to which it is morphologically most similar. Cambarus polypilosus sp. nov. appears to be common in cherty gravel and cobble habitats, where it is typically found in interstices at depths of 0.3 m or more below the substrate surface.


Asunto(s)
Astacoidea , Distribución Animal , Animales , Tamaño Corporal , Masculino , Ríos , Tennessee
17.
Zootaxa ; 4524(3): 329-350, 2018 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-30486112

RESUMEN

The obligately parthenogenetic marbled crayfish, Procambarus virginalis, is the first formally described asexual species of the Crustacea Decapoda. It is a triploid descendant of the sexually reproducing slough crayfish, Procambarus fallax. Here we describe the morphology of cultured and wild marbled crayfish of wide size ranges in detail and photodocument all taxonomically relevant characters. Some morphological traits and coloration showed considerable variation within populations despite the monoclonal nature of marbled crayfish. There were also significant differences between wild and laboratory populations with respect to body proportions, coloration and spination. Comparison with Procambarus fallax revealed no qualitative morphological characters that unambiguously identify the marbled crayfish. Analysis of the mitochondrial cytochrome c oxidase subunit I gene (COI) and nuclear microsatellites of marbled crayfish and Procambarus fallax from different sources indicated that the tri-allelic microsatellite PclG-02 is better suitable than COI to identify the marbled crayfish. A respective identification key is provided. The COI and microsatellites of Procambarus fallax from different areas of Florida and southern Georgia suggest that the parents of the first marbled crayfish may have come from northern Union County, northern Florida.


Asunto(s)
Astacoidea , Genotipo , Animales , Florida , Partenogénesis
18.
Zootaxa ; 4273(4): 576-586, 2017 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-28610233

RESUMEN

Targeted sampling efforts by the authors for the signal crayfish, Pacifastacus leniusculus, from its native range in the John Day River Basin, Oregon, U.S.A. yielded entocytherid ostracods with a male copulatory complex so clearly different from other entocytherines that a new genus, Aurumcythere gen. nov. is proposed to receive them. This newly proposed, apparently nonsclerotized, genus with hook and spur-like prominences of the posteroventral end of the peniferum is the first new genus of the subfamily Entocytherinae named since Hobbs & Peters described Aphelocythere (= Waltoncythere) in 1977. Aurumcythere gen. nov. represents only the second genus of entocytherid known from the Pacific Northwest. Lack of sclerotization in Aurumcythere gen. nov. provides new insight into poorly understood mating behaviors of entocytherid ostracods.


Asunto(s)
Astacoidea , Animales , Masculino , Oregon , Ríos
19.
PeerJ ; 4: e1915, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27114875

RESUMEN

Molecular genetic approaches are playing an increasing role in conservation science by identifying biodiversity that may not be evident by morphology-based taxonomy and systematics. So-called cryptic species are particularly prevalent in freshwater environments, where isolation of dispersal-limited species, such as crayfishes, within dendritic river networks often gives rise to high intra- and inter-specific genetic divergence. We apply here a multi-gene molecular approach to investigate relationships among extant species of the crayfish genus Pacifastacus, representing the first comprehensive phylogenetic study of this taxonomic group. Importantly, Pacifastacus includes both the widely invasive signal crayfish Pacifastacus leniusculus, as well as several species of conservation concern like the Shasta crayfish Pacifastacus fortis. Our analysis used 83 individuals sampled across the four extant Pacifastacus species (omitting the extinct Pacifastacus nigrescens), representing the known taxonomic diversity and geographic distributions within this genus as comprehensively as possible. We reconstructed phylogenetic trees from mitochondrial (16S, COI) and nuclear genes (GAPDH), both separately and using a combined or concatenated dataset, and performed several species delimitation analyses (PTP, ABGD, GMYC) on the COI phylogeny to propose Primary Species Hypotheses (PSHs) within the genus. All phylogenies recovered the genus Pacifastacus as monophyletic, within which we identified a range of six to 21 PSHs; more abundant PSHs delimitations from GMYC and ABGD were always nested within PSHs delimited by the more conservative PTP method. Pacifastacus leniusculus included the majority of PSHs and was not monophyletic relative to the other Pacifastacus species considered. Several of these highly distinct P. leniusculus PSHs likely require urgent conservation attention. Our results identify research needs and conservation priorities for Pacifastacus crayfishes in western North America, and may inform better understanding and management of P. leniusculus in regions where it is invasive, such as Europe and Japan.

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