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1.
Sci Data ; 10(1): 872, 2023 12 06.
Article in English | MEDLINE | ID: mdl-38057322

ABSTRACT

In the summer of 2012, two fires affected Mediterranean ecosystems in the eastern Iberian Peninsula. The size of these fires was at the extreme of the historical variability (megafires). Animals are traditionally assumed to recolonize from source populations outside of the burned area (exogenous regeneration) while plants recover from endogenous regeneration (resprouting and seeding). However, there is increasing evidence of in situ fire survival in animals. To evaluate the effect of large-scale fires on biodiversity and the mechanism of recovery, in 2013, we set up 12 plots per fire, covering burned vegetation at different distances from the fire perimeter and unburned vegetation. In each plot, we followed the postfire recovery of arthropods, reptiles (including some of their parasites), and plants for 2 to 5 years. Here we present the resulting database (POSTDIV) of taxon abundance. POSTDIV totals 19,906 records for 457 arthropod taxa (113,681 individuals), 12 reptile taxa (503 individuals), 4 reptile parasites (234 individuals), and 518 plant taxa (cover-abundance). We provide examples in the R language to query the database.


Subject(s)
Arthropods , Fires , Animals , Biodiversity , Ecosystem , Plants , Reptiles , Databases, Factual
2.
PLoS One ; 17(7): e0270032, 2022.
Article in English | MEDLINE | ID: mdl-35793291

ABSTRACT

Studying collection specimens is often the only way to unravel information about recent extinctions. These can reveal knowledge on threats and life traits related to extinction, and contribute, by extrapolation, to the conservation of extant species. However, high-throughput sequencing methods have rarely been applied to extinct species to reveal information on their ecology. Insular species are especially prone to extinction. We studied the gut contents of three specimens of the extinct giant skink Chioninia coctei of the Cabo Verde Islands using microscopy and DNA-metabarcoding. The presence of Tachygonetria adult nematodes suggests plants as important diet items. Our metabarcoding approach also identified plants and, additionally, invertebrates, supporting the hypothesis of C. coctei's generalist diet. The absence of vertebrates in the digestive contents may reflect the decline of seabirds on the Desertas Islands that could have contributed to the debilitation of the giant skink, already depleted by persecution and severe droughts. Even with a small sample size, this study contributes to shedding light on the trophic roles of this enigmatic extinct species and emphasizes the need to develop holistic conservation plans for island threatened taxa. Additionally, it illustrates the potential of integrating up-to-date molecular methods with traditional approaches to studying collection specimens to help to solve ecological puzzles in other ecosystems.


Subject(s)
Diet , Extinction, Biological , Specimen Handling , Animals , Cabo Verde , Diet/history , Diet/veterinary , Ecosystem , History, 20th Century
3.
Mol Ecol ; 27(2): 533-549, 2018 01.
Article in English | MEDLINE | ID: mdl-29219226

ABSTRACT

Episodes of expansion and isolation in geographic range over space and time, during which parasites have the opportunity to expand their host range, are linked to the development of host-parasite mosaic assemblages and parasite diversification. In this study, we investigated whether island colonization events lead to host range oscillations in a taxon of host-specific parasitic nematodes of the genus Spauligodon in the Canary Islands. We further investigated whether range oscillations also resulted in shifts in host breadth (i.e., specialization), as expected for parasites on islands. Parasite phylogeny and divergence time estimates were inferred from molecular data with Bayesian methods. Host divergence times were set as calibration priors after a priori evaluation with a global-fit method of which individual host-parasite associations likely represent cospeciation links. Parasite colonization history was reconstructed, followed by an estimation of oscillation events and specificity level. The results indicate the presence of four Spauligodon clades in the Canary Islands, which originated from at least three different colonization events. We found evidence of host range oscillations to truly novel hosts, which in one case led to higher diversification. Contemporary host-parasite associations show strong host specificity, suggesting that changes in host breadth were limited to the shift period. Lineages with more frequent and wider taxonomic host range oscillations prior to the initial colonization event showed wider range oscillations during colonization and diversification within the archipelago. Our results suggest that a lineage's evolutionary past may be the best indicator of a parasite's potential for future range expansions.


Subject(s)
Biological Evolution , DNA, Mitochondrial/genetics , Oxyuroidea/genetics , Phylogeny , Animals , Bayes Theorem , Host Specificity , Host-Parasite Interactions/genetics , Oxyuroidea/pathogenicity , Spain , Species Specificity
4.
Parasitol Res ; 113(3): 893-901, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24318748

ABSTRACT

Gnathostomatid nematodes identified morphologically as Spiroxys japonica Morishita, 1926 were collected from the dark-spotted frog Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae) in China. Light and scanning electron microscopy were used to study the morphology of this species in detail. Previously unreported morphological features are revealed and others corrected. In addition, adult nematodes of S. japonica collected from P. nigromaculatus and Spiroxys hanzaki Hasegawa, Miyata & Doi, 1998 collected from Andrias japonicus (Temminck) (Caudata: Cryptobranchidae) in China and Japan, respectively, and the third-stage larva of S. japonica collected from Lithobates catesbeianus (Shaw) (Anura: Ranidae) in Japan, were characterised using molecular methods by sequencing and analysing ribosomal [large ribosomal DNA (18S) and internal transcribed space] and mitochondrial [cytochrome c oxidase subunit 1] target regions, respectively. The new morphological and genetic data contributes to a more accurate diagnosis of this hitherto little known nematode genus.


Subject(s)
Ranidae/parasitology , Spirurida/genetics , Spirurida/ultrastructure , Animals , Base Sequence , China , DNA, Helminth/genetics , DNA, Mitochondrial/genetics , DNA, Ribosomal Spacer/genetics , Female , Japan , Male , Molecular Sequence Data , RNA, Ribosomal, 18S/genetics , Spirurida/classification , Urodela/parasitology
5.
Parasitol Res ; 112(12): 4001-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23999900

ABSTRACT

Parasitological analyses are often based on invasive methodologies, involving host sacrifice, raising ethical and conservation issues. However, alternative non-invasive approaches may not be always applicable due to the location of the parasite in the host tissue or the quality and reliability of the non-invasive sample per se. In this study, we compare the differences in detectability of intestinal parasites in reptiles using the classical invasive approach (intestine dissection), versus a non-invasive procedure (faecal examination), collected from the same individual host. Our results showed significantly lower detectability of helminths in faeces versus the intestine. Moreover, the number of parasites found in faeces was not explained either by the intensities found in the respective intestine or by the host identity. Several factors may explain the lack of association between the two types of samples, but more importantly, our results highlight the randomness of the presence of parasites in faeces. Even if it is not recommended that comparative studies of either parasite abundance or parasite communities be conducted on the basis of faecal samples, there are other types of studies (i.e. genetic) that can be performed with this source of information, thus avoiding the sacrifice of the host. Due to their wide spectrum of life stages and localization in the host tissue, parasites are challenging candidates for non-invasive sampling and consequently, parasitological methodologies should be carefully selected according to the objective of the study.


Subject(s)
Feces/parasitology , Helminths/isolation & purification , Intestinal Diseases, Parasitic/diagnosis , Reptiles/parasitology , Animals , Intestinal Diseases, Parasitic/veterinary , Lizards/parasitology , Reproducibility of Results
6.
J Parasitol ; 98(1): 160-6, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21942458

ABSTRACT

A new nematode species, Spauligodon nicolauensis n. sp., is described from geckos Tarentola bocagei and Tarentola nicolauensis on the island of São Nicolau, Cape Verde. The new nematode was found in the pellets obtained directly from the geckos in a non-invasive fashion, and its identity was assessed both at morphologic and genetic levels. The new species has morphological similarities with Spauligodon tarentolae Spaul, 1926, also parasitizing geckos from the Canary Islands. However, the male cloacal region in the new species is distinct, presenting a different shape of the caudal papillae. The overall resemblance probably resulted from colonization via descent from an ancestor of S. tarentolae carried by the ancestor of Cape Verde Tarentola. The analysis of nuclear DNA sequences confirms that the new species is phylogenetically distinct from all other Spauligodon species already analyzed, forming a group clearly separated from species parasitizing lacertid lizards. The COI genetic distance suggests that the S. nicolauensis n. sp. found in the 2 species of geckos in São Nicolau Island may have resulted from a host-switching event, when they came into contact after the unification of the island.


Subject(s)
Lizards/parasitology , Oxyuriasis/veterinary , Oxyuroidea/classification , Phylogeny , Animals , Base Sequence , Bayes Theorem , Cabo Verde/epidemiology , Cyclooxygenase 1/genetics , DNA, Helminth/chemistry , Feces/parasitology , Female , Male , Oxyuriasis/epidemiology , Oxyuriasis/parasitology , Oxyuroidea/anatomy & histology , Oxyuroidea/genetics , Prevalence , RNA, Ribosomal, 28S/chemistry , RNA, Ribosomal, 28S/genetics , Sequence Alignment/veterinary
7.
Syst Parasitol ; 80(1): 53-66, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21805391

ABSTRACT

Parasite taxonomy traditionally relies on morphometric and life-cycle characteristics which may not reflect complex phylogenetic relationships. However, genetic analyses can reveal cryptic species within morphologically described parasite taxa. We analysed the phylogenetic variation within the nematode Spauligodon atlanticus Astasio-Arbiza, Zapatero-Ramos, Ojeda-Rosas & Solera-Puertas, 1987, a parasite of the Canarian lizard genus Gallotia Boulenger, inferring the origin of their current association. We also attempted to determine its relationship with other Spauligodon spp. Three different markers, mitochondrial COI plus nuclear 18S and 28S ribosomal RNA, were used to estimate the evolutionary relationships between these nematodes. S. atlanticus was found to be paraphyletic, suggesting that Gallotia spp. were colonised by two independent lineages of Spauligodon. Additional analyses of other Spauligodon spp. are required for a more complete interpretation of the evolution of this genus from the Canarian archipelago and its closest taxa. Our results emphasise the importance of extensive sampling and phylogenetic studies at the intrageneric level, and highlight the limitations of a morphologically based taxonomy in these parasites.


Subject(s)
Lizards/parasitology , Oxyuroidea/classification , Phylogeny , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 28S/genetics , Animals , Base Sequence , Bayes Theorem , Biomarkers , Cecum/parasitology , Evolution, Molecular , Oxyuroidea/genetics , Oxyuroidea/isolation & purification , Sequence Alignment , Spain
8.
J Parasitol ; 90(2): 266-70, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15165048

ABSTRACT

A survey of gastrointestinal helminth communities of Gallotia caesaris caesaris (Lehrs, 1914) and G. c. gomerae (Boettger and MUller, 1914), from the islands of El Hierro and La Gomera, respectively, in the Canary Archipelago, Spain, was conducted to determine the prevalence, intensity, and diversity of intestinal parasites of these lacertid lizards. Larval forms of cestodes, nematodes, and acanthocephalans were found in the body cavity of G. c. caesaris; this lizard is the intermediate or paratenic host in the life cycle of these helminths. Pharyngodonid nematodes were the most common intestinal helminths in both hosts, 4 of them being Gallotia spp. specialists. Helminth infracommunities of both hosts were depauperate and isolationist, according to the low values of helminth diversity.


Subject(s)
Helminthiasis, Animal/parasitology , Helminths/classification , Intestinal Diseases, Parasitic/veterinary , Lizards/parasitology , Animals , Atlantic Islands/epidemiology , Helminthiasis, Animal/epidemiology , Helminths/growth & development , Helminths/isolation & purification , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/parasitology , Prevalence
9.
Rev. ortop. traumatol. (Madr., Ed. impr.) ; 46(1): 20-25, feb. 2002. tab, graf
Article in Es | IBECS | ID: ibc-11313

ABSTRACT

Para conocer la fiabilidad de las prótesis porosas a largo plazo, los autores realizan un estudio retrospectivo revisando una serie consecutiva y no seleccionada de 68 prótesis de cadera no cementadas con ambos componentes porosos (AML), que habían cumplido al menos una década desde su implantación. De ellas 9 no tenían datos actuales y 5 fallecieron por causas ajenas a la intervención. Los 54 pacientes restantes, operados con una edad media de 65 años, fueron seguidos durante más de 10 años (125 meses de media). En 8 ocasiones (14,8 por ciento) tuvieron que ser reintervenidos, 2 casos por aflojamiento del cótilo, 1 por aflojamiento del vástago y en 5 ocasiones por desgaste del componente de polietileno, alcanzando un resultado satisfactorio tras la intervención. Al superar los 10 años, el 85,2 por ciento de los pacientes mantienen los componentes originales con un resultado satisfactorio en el 84,9 por ciento de los casos. Sólo en 1 de ellos la puntuación fue de 12 y se consideró como mediocre. La probabilidad de supervivencia del implante fue de 0,89 ñ 0,01.A pesar de encontrar signos radiológicos de desfuncionalización metafisaria en el 35 por ciento de los casos, sin aumento en relación con la revisión a los 5 años, ninguno de ellos tuvo repercusión clínica.Las prótesis porosas no cementadas han demostrado unos resultados fiables a largo plazo en pacientes no seleccionados. Queda demostrada la eficacia de la fijación con un porcentaje de aflojamientos asépticos inferior al de las prótesis cementadas, quedando por mejorar en un futuro los problemas de desgaste (AU)


Subject(s)
Aged , Female , Male , Middle Aged , Humans , Arthroplasty, Replacement, Hip/methods , Bone Substitutes/analysis , Porosity , Osteoarthritis, Hip/surgery , Treatment Outcome , Retrospective Studies , Prosthesis Failure
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