5,797 research outputs found

    Power Series Solutions of Non-Linear q-Difference Equations and the Newton-Puiseux Polygon

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    Adapting the Newton-Puiseux Polygon process to nonlinear q-difference equations of any order and degree, we compute their power series solutions, study the properties of the set of exponents of the solutions and give a bound for their qq-Gevrey order in terms of the order of the original equation

    Plusiotis ericsmithi (Coleoptera: Scarabaeidae) : a new metallic species from eastern Guatemala

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    Se describe Plusiotis ericsmithi sp. nov. de un bosque nuboso de baja altitud (1100 msnm) en la Sierra del Merend6n, Guatemala, cerca de la front era con Honduras. Ademas, se incluyen ilustraciones de los genitales masculinos y femeninos.Plusiotis ericsmithii n. sp. is described from a low altitude cloud forest (1100 m) in the Guatemalan Merend6n mountain chain near the Honduran border. Male and female genitalia are illustrated

    Colossendeis species (Pycnogonida: Colossendeidae) collected during the Italica XIX cruise to Victoria Land (Antarctica), with remarks on some taxonomic characters of the ovigers

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    The pycnogonid fauna of the genus Colossendeis collected during the Italica XIX cruise to Victoria Land (Ross Sea, Antarctica) was studied. A total of 19 specimens of six species were collected: Colossendeis australis (6), C. wilsoni (3), C. scotti (2), C. robusta (3), C. lilliei (2) and C. megalonyx (3). In the present contribution the observed variability of all collected Colossendeis species is described and illustrated. The previously synonymised C. lilliei is considered a different species from C. robusta. The observations made in this study lead us to discuss a controversy about the total number of oviger segments in this genus. Despite the currently established 10-segmented status, a short basal element is here considered to be a possible 11th segment. A detailed SEM study of the last oviger segment is carried out in all collected species, showing some intraspecific and the interspecific variability in the structures examined (shape and number of rows of compound spines, morphology of terminal claw, etc.). Finally, we discuss the taxonomic value of these characters of the last strigilis segment for distinguishing the Colossendeis species, and their possible utility in establishing internal phylogenetic relationships in future contributions

    New findings and a new species of the genus Ammothea (Pycnogonida, Ammotheidae), with an updated identification key to all Antarctic and sub-Antarctic species

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    Specimens of the pycnogonid genus Ammothea collected during the Polarstern cruise XXIII/8 (23 November 2006–30 January 2007) were studied. Nine species were recognized in this collection: Ammothea bentartica, A. bicorniculata, A. carolinensis, A. clausi, A. longispina, A. minor, A. spinosa, A. striata and A. tibialis. Three of them (A. bentartica, A. bicorniculata and A. tibialis) are reported for the second time, enlarging their known geographical and bathymetric range. In the present contribution, the observed morphological variability of all collected Ammothea species is described and discussed. For the identification and description of the material, different museum specimens were consulted. Among them, we have consulted part of the Discovery collection housed at the Natural History Museum in London. That material was initially identified by Isabella Gordon, a reputed author in the field of pycnogonid taxonomy. A new species, based on a museum specimen previously highly confused in the literature, is proposed in the present contribution as Ammothea isabellae n. sp. The new taxon is compared with its closest congeners, especially with A. longispina and A. stylirostris. Finally, we propose an updated dichotomous key to species covering all currently known Antarctic and sub-Antarctic Ammothea specie

    Two new species of Ammothea (Pycnogonida, Ammotheidae) from Antarctic waters

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    Two new species of the genus Ammothea are described from Elephant Island and the South Shetlands Islands, Antarctica. The material was captured during the Polarstern cruise XXIII/8 to the Antarctic Peninsula area. The main features of Ammothea pseudospinosa n. sp. are a proboscis distinctly trilobulated distally with a constriction at 2/3 of its length and dimorphism between the propodi of the anterior (first and second) and posterior (third and fourth) legs, and a trunk: proboscis length ratio of about 1.5. The main features of Ammothea childi n. sp. are a cylindrical proboscis, longer than trunk length, and adults with functional chelifores. These species are compared with their closest congeners from the Southern Ocean: A. pseudospinosa n. sp. with Ammothea spinosa and Ammothea allopodes;A. childi n. sp. withAmmothea gigantea, Ammothea bicorniculata and Ammothea hesperidensis

    Nuevo modo de desarrollo postembrionario en el género Ammothea (Pycnogonida: Ammotheidae) procedente de aguas Antárticas

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    In this paper the postembryonic development of Ammothea glacialis (family ammotheidae) is described. The studied material was collected during the Italica XIX cruise to Victoria land, ross sea, antarctica. The external morphology of three larval instars is described and illustrated. The development of A. glacialis has the following characteristics: (1) protonymphon hatch from the eggs; (2) the larvae have yolk reserves and relatively large size (0.7 mm in length); (3) the larvae remain on the ovigerous legs of males during several moults; (4) the larvae have reduced larval II-III appendages and the spinning apparatus is absent; (5) the development of walking legs is sequential. This development is compared with those previously known, especially with Propallene longiceps and Nymphon grossipes.Nuevo modo de desarrollo postembrionario en el género AmmotheA (Pycnogonida: Ammotheidae) procedente de aguas Antárticas. – En este trabajo se describe el desarrollo postembrionario de Ammothea glacialis (familia ammotheidae). El material estudiado fue recolectado durante el crucero Itálica XIX a Tierra Victoria, en el mar de ross, antártida. se describe e ilustra la morfología externa de tres estadios larvarios. El desarrollo de A. glacialis se caracteriza por: (1) la larva eclosiona como protonymphon; (2) la larva es de tamaño relativo grande (0.7 mm de longitud) y con reservas de vitelo; (3) la larva permanece en los ovígeros del macho durante varias mudas; (4) la larva presenta los apéndices larvarios II y III reducidos y el “spinning apparatus” está ausente; (5) el desarrollo de las patas es secuencial. Este desarrollo es comparado con otros desarrollos postembrionarios previamente conocidos, especialmente con los de Propallene longiceps and Nymphon grossipes

    Bioethics and health law: the living will. Proposal to create a living will record in Europe

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    In this piece of work, we present a proposal to create a living will record in Europe that will allow people to have the same rights wherever they are. Therefore, this article will be studied from the bioethics and health law theory

    Notes on Guatemalan Plusiotis (Coleoptera: Scarabaeidae; Rutelinae)

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    Dos especies nuevas de escarabajos del genero Plusiotis se describen de un bosque nuboso, 1560-1900 m en el departamento de San Marcos, Guatemala. Tambien se describen las hembras de P. turhheimi Ohaus, P. auropunctata Ohaus y P. quiche Moron. Ademas, se registra pOI' primera vez a P. turhheimi para Guatemala.Two new species of Plusiotis are described from a cloud forest between 1560-1900 m in the Department of San Marcos, Guatemala. Females of P. turhheimi Ohaus, P. auropunctata Ohaus and P. quiche Moron are described. Plusiotis turhheimi is reported from Guatemala for the first time
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