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1.
J Parasitol ; 110(4): 300-310, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39034041

RESUMEN

Enteric parasites can have wide-ranging effects throughout an ecosystem, often driving coevolutionary and ecological processes. Parasites have long been overlooked in conservation efforts because of the negative impact inflicted on their hosts; however, parasites make up a significant component of Earth's biodiversity and host conservation efforts need to be parasite inclusive. The Vancouver Island marmot (VIM), Marmota vancouverensis, is an endangered alpine rodent endemic to Vancouver Island, British Columbia, Canada. Captive-bred VIMs are released to augment the wild population, but their susceptibility to parasites is unknown. The objectives of this study were to describe the diversity, prevalence, severity, and temporal variation of VIM enteric parasites. Noninvasive fecal samples were collected from wild and captive marmots and analyzed using a modified McMaster fecal egg floatation technique to indicate parasite prevalence and relative mean abundance. We identified oocysts and ova from 3 parasite taxa including a protozoan coccidium not previously described in the VIM (prevalence 68%), an ascarid nematode Baylisascaris laevis (prevalence 82%), and an anoplocephalid cestode Diandrya vancouverensis (prevalence 8%). Depending on the species, comparisons revealed variation in parasite infection by sex, by colony, and between wild and captive VIMs, but not among age classes or by female reproductive status. Finally, captive VIMs displayed significant monthly variation in parasite prevalence and mean egg abundance, suggesting a seasonal influence on parasite egg shedding. This information is critically important for future research investigating the influences of these trends on the health, ecology, and conservation of VIMs and their parasites.


Asunto(s)
Especies en Peligro de Extinción , Heces , Parasitosis Intestinales , Marmota , Dinámica Poblacional , Animales , Marmota/parasitología , Colombia Británica/epidemiología , Heces/parasitología , Femenino , Masculino , Prevalencia , Parasitosis Intestinales/veterinaria , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/epidemiología , Estaciones del Año , Animales Salvajes/parasitología
2.
Biodivers Data J ; 12: e115464, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38586529

RESUMEN

Background: With this publication, we contribute to the knowledge of the arachnofauna of Cabo Verde, focusing specifically on the Islands of Santo Antão and São Vicente. Data were obtained from samples collected as part of the project "Macaronesian Islands as a testing ground to assess biodiversity drivers at multiple scales" (FCT - MACDIV, 2015-2018). This project aimed to identify the factors influencing community assembly in Macaronesian islands. For the Cabo Verde Islands, we focused on dry habitats with the additional aim to revise the aracnofauna of this poorly-known fauna. We applied the COBRA (Conservation Oriented Biodiversity Rapid Assessment) sampling protocol in ten 50 m x 50 m dry shrub plots, with five on each of the two islands, using pitfall traps, sweep-netting and active search. Additional ad-hoc samples were also collected and reported. New information: Our sampling of spiders from Cabo Verde (Santo Antão and São Vicente) yielded a total of 3,368 specimens, of which 1300 (39%) were adults. The samples include 21 families, 87 species, 18 of which are morphospecies awaiting formal identification or description at species level. Species in the families Oxyopidae (2 spp.) and Araneidae (8 spp.) were the most abundant, making up 49% of the specimens. From the 68 named species, 14 are endemic to Cabo Verde, 40 are native non-endemic and 14 are introduced. The colonisation status of Cithaeronreimoseri Platnick, 1991 is unknown. Endemic species accounted for 24% (n = 818) of the specimens and native non-endemic for 63% (n = 2122). A total of 29 species were new records for Cabo Verde, with 15 for Santo Antão, seven for São Vicente and seven for both Islands.

3.
Biodivers Data J ; 10: e78457, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35437397

RESUMEN

Background: The extensive forests over limestone of the Samar Island Natural Park (SINP) on Samar Island, Philippines harbour a rich variety of unique species. In this contribution, we describe and illustrate a new Loranthaceous mistletoe, endemic to Samar Island named Decaisninatomentosa, representing the 12th member of the genus reported to the Philippines. New information: This new species is similar to D.confertiflora (Merr.) Barlow with respect to the presence of shortly and densely off-white tomentose inflorescence and 6-merous flowers. However, it is unique amongst congeners in having tomentose and partially fused bracteoles which cover almost or entirely the ovary of individual flowers in the triads. To date, D.tomentosa seems to be restricted to the SINP and is only known from a handful of individuals. More studies are needed to properly assess the demography, host range, conservation status and phylogenetic position of this distinctive species of mistletoe.

4.
J Anim Ecol ; 90(2): 460-470, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33080048

RESUMEN

A single adverse environment event can threaten the survival of small-ranged species while random fluctuations in population size increase the extinction risk of less-abundant species. The abundance-range-size relationship (ARR) is usually positive, which means that smaller-ranged species are often of low abundance and might face both problems simultaneously. The ARR has been reported to be negative on tropical islands, perhaps allowing endemic species in such environments to remain extant. But there is a need to understand how endemism and land-use interact to shape ARR. Using 41 highly replicated transects along the full elevational gradient of Sri Lanka, we determined the following: (a) the direction of ARR, (b) if endemism affects ARR and (c) if land-use (rainforest, buffer and agriculture) changes ARR differently for endemics and non-endemics. Additionally, (d) we identified endemics that had both lower abundances and smaller range sizes, and ranked them from most threatened (specific to rainforests) to least threatened using a weighted-interaction nestedness estimator. (a) We found a positive relationship between species abundances and range size. This positive ARR was maintained among endemic and non-endemic species, across land-use types and at local and regional scales. (b) The ARR interacted with endemicity and land-use. Endemics with smaller range sizes had higher abundances than non-endemics, and particularly higher in rainforests compared to agriculture. In contrast, species with larger range sizes had similar abundances across endemicity and land-use categories. Many endemics with smaller range sizes are globally threatened; therefore, higher abundances may buffer them from extinction risks. (c) Nine (29%) endemics had both below average abundance and elevational range size. The nestedness estimator ranked the endemics Sri Lanka Whistling Thrush Myophonus blighi, Red-faced Malkoha Phaenicophaeus pyrrhocephalus, Sri Lanka Thrush Zoothera imbricata and White-faced Starling Sturnornis albofrontus as the four most vulnerable species to local extinction risk, which corresponds to their global extinction risk. We demonstrate that ARR can be positive on tropical islands, but it is influenced by endemism and land-use. Examining shifts in ARR is not only important to understand community dynamics but can also act as a tool to inform managers about species that require monitoring programmes.


Asunto(s)
Biodiversidad , Aves , Animales , Ecosistema , Islas , Densidad de Población , Bosque Lluvioso
5.
PhytoKeys ; 152: 121-136, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32733137

RESUMEN

Several genera of Nyctaginaceae, currently merged under Pisonia, have been described for the Indo-Pacific region. Results from a recent molecular phylogenetic study of tribe Pisonieae showed that Pisonia is non-monophyletic and comprises three well-supported lineages: one including typical Pisonia and allies (Pisonia s.str.), a clade of species which corresponds to the original description of Ceodes and a third lineage whose single representative was formerly treated under the monotypic genus Rockia. Thus, as part of an effort to achieve a natural classification for tribe Pisonieae, this work proposes to re-establish Ceodes and Rockia to accommodate taxa with inconspicuous glands on anthocarps, recognising 21 species (20 for the former and one for the latter), of which 16 are new combinations: Ceodes amplifolia comb. nov., Ceodes artensis comb. nov., Ceodes austro-orientalis comb. nov., Ceodes brownii comb. nov., Ceodes cauliflora comb. nov., Ceodes coronata comb. nov., Ceodes diandra comb. nov., Ceodes gigantocarpa comb. nov., Ceodes gracilescens comb. nov., Ceodes lanceolata comb. nov., Ceodes merytifolia comb. nov., Ceodes muelleriana comb. nov., Ceodes rapaensis comb. nov., Ceodes sechellarum comb. nov., Ceodes taitensis comb. nov. and Ceodes wagneriana comb. nov. A general distribution of each species recognised in this work is also included, along with line drawings and colour pictures of representative species of Ceodes, Pisonia and Rockia and an updated dichotomous key based on reproductive characters for the nine genera (Ceodes, Cephalotomandra, Grajalesia, Guapira, Neea, Neeopsis, Pisonia, Pisoniella and Rockia) comprising the tribe Pisonieae. Résumé Plusieurs genres de Nyctaginaceae actuellement fusionnés sous Pisonia ont été décrits pour la région Indo-Pacifique. Les résultats d'une récente étude phylogénétique moléculaire de la tribu Pisonieae ont montré que Pisonia est non monophylétique et comprend trois lignées bien supportées: une comprenant Pisonia typique et ses alliés (Pisonia s.str.), un clade d'espèces qui correspond à la description originale de Ceodes et une troisième lignée dont l'unique représentant était auparavant traité sous le genre monotypique Rockia. Ainsi, dans le cadre d'un effort pour parvenir à une classification naturelle de la tribu Pisonieae, ce travail proposons de rétablir les Ceodes et Rockia pour accueillir des taxons avec des glandes discrètes sur les anthocarpes, reconnaissant 21 espèces (20 pour les premières et une pour les dernières), dont 16 sont de nouvelles combinaisons: Ceodes amplifolia comb. nov., Ceodes artensis comb. nov., Ceodes austro-orientalis comb. nov., Ceodes brownii comb. nov., Ceodes cauliflora comb. nov., Ceodes coronata comb. nov., Ceodes diandra comb. nov., Ceodes gigantocarpa comb. nov., Ceodes gracilescens comb. nov., Ceodes lanceolata comb. nov., Ceodes merytifolia comb. nov., Ceodes muelleriana comb. nov., Ceodes rapaensis comb. nov., Ceodes sechellarum comb. nov., Ceodes taitensis comb. nov. et Ceodes wagneriana comb. nov. Une distribution générale de chaque espèce reconnue dans ce travail est également incluse, ainsi que des dessins au trait et des images en couleur des espèces représentatives de Ceodes, Pisonia et Rockia, et préparé une clé dichotomique mise à jour basée sur les caractères reproductifs des neuf genres (Ceodes, Cephalotomandra, Grajalesia, Guapira, Neea, Neeopsis, Pisonia, Pisoniella et Rockia) comprenant la tribu Pisonieae.

6.
Am J Bot ; 106(2): 313-324, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30768870

RESUMEN

PREMISE OF THE STUDY: Over one-third of the native flowering plant species in the Hawaiian Islands are listed as federally threatened or endangered. Lack of sufficient pollination could contribute to reductions in populations, reproduction, and genetic diversity among these species but has been little studied. METHODS: We used systematic observations and manual flower treatments to quantify flower visitation and outcrossing dependency of eight native (including four endangered) plant species in a dryland ecosystem in Hawaii: Argemone glauca, Bidens menziesii, Dubautia linearis, Haplostachys haplostachya, Sida fallax, Silene lanceolata, Stenogyne angustifolia, and Tetramolopium arenarium. KEY RESULTS: During 576.36 h of flower observations, only insects visited the flowers. Out of all recorded flower visits, 85% were performed by non-native species, particularly the honeybee (Apis mellifera) and flies in the family Syrphidae. Some plant species received little visitation (e.g., S. angustifolia received one visit in 120 h of observation), whereas others were visited by a wide diversity of insects. The endangered plant species were visited by fewer visitor taxa than were the common native plant species. For six of the focal plant species, bagging of flowers to exclude pollinators resulted in significant reductions in seed set. CONCLUSIONS: The flower visitor community in this system, although heavily dominated by non-native insects, appears to be facilitating pollination for multiple plant species. Non-native insects may thus be sustaining biotic interactions otherwise threatened with disruption in this island ecosystem. This may be particularly important for the studied endangered plant species, which exhibit fewer partners than the more common plant species.


Asunto(s)
Insectos , Especies Introducidas , Magnoliopsida , Polinización , Animales , Hawaii
7.
AoB Plants ; 72015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25979965

RESUMEN

Conservation of plant diversity on islands relies on a good knowledge of the taxonomy, distribution and genetic diversity of species. In recent decades, a combination of morphology- and DNA-based approaches has become the standard for investigating island plant lineages and this has led, in some cases, to the discovery of previously overlooked diversity, including 'cryptic species'. The flora of the Cape Verde archipelago in the North Atlantic is currently thought to comprise ∼740 vascular plant species, 92 of them endemics. Despite the fact that it is considered relatively well known, there has been a 12 % increase in the number of endemics in the last two decades. Relatively few of the Cape Verde plant lineages have been included in genetic studies so far and little is known about the patterns of diversification in the archipelago. Here we present an updated list for the endemic Cape Verde flora and analyse diversity patterns for three endemic plant lineages (Cynanchum, Globularia and Umbilicus) based on one nuclear (ITS) and four plastid DNA regions. In all three lineages, we find genetic variation. In Cynanchum, we find two distinct haplotypes with no clear geographical pattern, possibly reflecting different ploidy levels. In Globularia and Umbilicus, differentiation is evident between populations from northern and southern islands. Isolation and drift resulting from the small and fragmented distributions, coupled with the significant distances separating the northern and southern islands, could explain this pattern. Overall, our study suggests that the diversity in the endemic vascular flora of Cape Verde is higher than previously thought and further work is necessary to characterize the flora.

8.
Proc Biol Sci ; 281(1788): 20140339, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-24943365

RESUMEN

Exotic predators have driven the extinction of many island species. We examined impacts of feral cats on the abundance and anti-predator behaviours of Aegean wall lizards in the Cyclades (Greece), where cats were introduced thousands of years ago. We compared populations with high and low cat density on Naxos Island and populations on surrounding islets with no cats. Cats reduced wall lizard populations by half. Lizards facing greater risk from cats stayed closer to refuges, were more likely to shed their tails in a standardized assay, and fled at greater distances when approached by either a person in the field or a mounted cat decoy in the laboratory. All populations showed phenotypic plasticity in flight initiation distance, suggesting that this feature is ancient and could have helped wall lizards survive the initial introduction of cats to the region. Lizards from islets sought shelter less frequently and often initially approached the cat decoy. These differences reflect changes since islet isolation and could render islet lizards strongly susceptible to cat predation.


Asunto(s)
Evolución Biológica , Gatos/fisiología , Reacción de Fuga , Lagartos/fisiología , Conducta Predatoria , Animales , Gatos/genética , Femenino , Cadena Alimentaria , Grecia , Especies Introducidas , Islas , Lagartos/genética , Masculino , Densidad de Población
9.
Biodivers Data J ; (2): e1051, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24855443

RESUMEN

Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported - Ceratinopsis n. sp. and Theridion n. sp. - and the first records of Poecilonetavariegata (Blackwall, 1841) and Tetragnathaintermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island.

10.
J Biol Res (Thessalon) ; 21(1): 16, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25984499

RESUMEN

BACKGROUND: Greece has two island archipelagos, the Aegean and the Ionian, which host a rich array of plants and wildlife, particularly endemic and threatened plant species. Despite the long history of island biogeographic studies in the Aegean, similar studies in the Ionian remain limited, with the two island archipelagos rarely being compared. RESULTS: The Aegean and Ionian archipelagos share many features, especially regarding total plant diversity, but exhibit different patterns of endemism. For instance, when considering similarly sized islands, those in the Ionian host as many as, if not more, species compared to the Aegean. In contrast, the Ionian Islands are poor in endemics (particularly narrow range endemics, such as single island or regional endemics) and threatened taxa, compared to the Aegean Islands. In the Ionian, endemics only persist on the largest islands, and form a very small proportion of the species pool, compared to the Aegean archipelago. CONCLUSIONS: The lack of endemism might be attributed to the more recent separation of the Ionian Islands from the mainland and the shorter distance separating them from the mainland. In addition, the Ionian Islands receive higher levels of precipitation and are typically covered by denser and higher vegetation than the Aegean Islands. These conditions favour greater total species richness, but tend to lead to higher numbers of common species compared to threatened and endemic taxa. This study demonstrates that both isolation and precipitation serve as biodiversity drivers, influencing plant species diversity and endemism patterns, of the two Greek archipelagos.

11.
Herpetologica ; 58(3): 303-312, 2002.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1063283

RESUMEN

We describe a new pitviper species, Bothrops alcatraz, of the Bothrops jararaca group, from Alcatrazes Island, off the coast of São Paulo, southeastern Brazil. It differs from the mainland coastal populations of B. jararaca in southeastern Brazil mostly by its darker coloration; smaller size; lower number of ventrals, subcaudals, and infralabials; number and shape of anterior cephalic scales; shape of hemipenis spines; intense coagulant activity of venom; and three specific venom proteins. From Bothrops insularis, another island species from southeastern Brazil, the new species differs mainly by its color pattern, smaller size, lower number of subcaudals in males, and absence of hemiclitoris in females. Bothrops alcatraz presents some features that may be viewed as paedomorphic within the B. jararaca group, such as small adult size, proportionally large eyes,intense coagulant venom activity, and diet composed of centipedes and lizards. We postulate that the dwarfism and characteristics of venom in B. alcatraz may be related to its diet (similar to thatof juveniles of the mainland B. jararaca). Bothrops alcatraz and B. insularis may have originatedthrough the isolation of populations of a B. jararaca-like ancestor on the Alcatrazes and Queimada Grande islands, respectively. The new species is regarded as critically endangered due to its very small area of occurrence and the declining quality of its habitat.


Asunto(s)
Animales , Bothrops/clasificación , Bothrops/crecimiento & desarrollo , Serpientes , Historia Natural
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