Sihler's Staining of the Thoracic Cutaneous Nerve and its Significance / Tinción de Sihler del Nervio Cutáneo Torácico y su Relevancia

SUMMARY: Our team has modified Sihler's intramuscular nerve staining method to allow for calculation of nerve density. Therefore, this study aimed to show the overall distribution pattern of the thoracic cutaneous nerves to provide a morphological basis for selecting and matching sensory reconstruction during skin flap transplantation. Twelve Chinese adult cadavers were dissected; the thoracic skin was removed, and the modified Sihler's staining method was performed. Centered around the nipple, the chest skin was divided into four regions: medial-superior, lateral-superior, lateral-inferior, and medial-inferior. The thoracic skin was not only innervated by the branches of the 1st to 7th intercostal and supraclavicular nerves, but also by a small number of nerves that directly reached the skin and passed through the pectoralis major muscle. There is a phenomenon of cross overlap between the branches of adjacent intercostal nerves. The branches of the 2nd to 7th intercostal nerves were distributed in the breast, and the branches of the lateral and anterior cutaneous branches were densely distributed around the nipple, forming a grid-like anastomosis. There was no cross-overlapping innervation between the anterior cutaneous branches on both sides. The density of nerve distribution in the four regions of the chest was in the order of the medial-superior, lateral-superior, lateral-inferior and medial-inferior region, respectively. These results may be used to map sensory regions when designing thoracic skin flaps for reconstruction surgery to obtain improved sensory recovery.

Nuestro equipo ha modificado el método de tinción nerviosa intramuscular de Sihler para permitir el cálculo de la densidad nerviosa. Por lo tanto, este estudio tuvo como objetivo mostrar el patrón de distribución general de los nervios cutáneos torácicos proporcionando una base morfológica para seleccionar y combinar la reconstrucción sensorial durante el trasplante de colgajo de piel. Se diseccionaron 12 cadáveres de individuos adultos chinos. Se eliminó la piel torácica y se realizó el método de tinción de Sihler modificado, centrada alrededor del pezón, la piel del pecho se dividió en cuatro regiones: medial- superior, lateral-superior, lateral-inferior y medial-inferior. La piel torácica no solo estaba inervada por los ramos de los nervios intercostal y supraclavicular 1º a 7º, sino también por un pequeño número de nervios que llegaban directamente a la piel y pasaban a través del músculo pectoral mayor. Existe un fenómeno de superposición cruzada entre los ramos de los nervios intercostales adyacentes. Los ramos de los nervios intercostales 2º a 7º se distribuyeron en la mama, y los ramos de los ramos cutáneos lateral y anterior se distribuyeron densamente alrededor del pezón, formando una anastomosis en forma de rejilla. No hubo inervación cruzada entre los ramos cutáneos anteriores en ambos lados. La densidad de la distribución nerviosa en las cuatro regiones del tórax estaba en el orden de región medial-superior, lateral-superior, lateral-inferior y medial-inferior, respectivamente. Estos resultados pueden ser útiles para mapear regiones sensoriales al diseñar colgajos de piel torácicos para utilizarlos en cirugía de reconstrucción y obtener así una mejor recuperación sensorial.

A new species of Dilophochila Bates, 1888 with comments on natural history and distribution of the genus (Coleoptera: Melolonthidae: Rutelinae)

A new species, Dilophochila glabrasp. nov. is described from the Sierra Norte, Oaxaca, Mexico. Diagnosis and im-ages (dorsal, lateral and ventral habitus, and genitalia) of the taxonomic characters are provided. Affinities with their clos-est congeners and the general distribution pattern of the genus are discussed, considering that it presents a typical Mountain Paleoamerican sub-pattern. The modifications in the mouthparts of this genus due to the specialization in the intake of pine needles are commented, as well as in two other different taxa within Anomalini.(AU)

Geographic distribution, conservation status and lectotypification of Pedersenia weberbaueri (Suess.) Holub (Amaranthaceae), an endemic and highly threatened shrub from the Marañón valley of Peru

The present study analyses the geographical distribution, conservation status, and nomenclature of Peruvian endemic Pedersenia weberbaueri. The species distribution was modelled using MaxEnt based on occurrence data and bioclimatic variables. The conservation status of the species was assessed against the categories and criteria of the IUCN Red List, and nomenclatural and typification issues were resolved. The potential distribution map of P. weberbaueri shows that the species is restricted to the seasonally dry tropical forests of the Marañón valley within a narrow latitudinal, longitudinal, and elevational range. Consequently, we propose to categorise the species as Endangered (EN) and provide the necessary information for its inclusion in the IUCN Red List. Finally, we resolve nomenclatural issues and designate a lectotype. The results contribute to the biological knowledge of P. weberbaueri and support subsequent conservation management plans.

El presente estudio analiza la distribución geográfica, el estado de conservación y la nomenclatura de la endémica peruana Pedersenia weberbaueri. La distribución de especies se modeló usando MaxEnt con base en datos de ocurrencia y variables bioclimáticas. Se evaluó el estado de conservación de la especie frente a las categorías y criterios de la Lista Roja de la UICN y se resolvieron cuestiones de nomenclatura y tipificación. El mapa de distribución potencial de P. weberbaueri muestra que la especie está restringida a los bosques tropicales estacionalmente secos del valle del Marañón dentro de un estrecho rango latitudinal, longitudinal y altitudinal. En consecuencia, proponemos categorizar a la especie como En Peligro (EN) y brindar la información necesaria para su inclusión en la Lista Roja de la UICN. Finalmente, resolvemos cuestiones de nomenclatura y designamos un lectotipo. Los resultados contribuyen al conocimiento biológico de P. weberbaueri y respaldan los planes de manejo de conservación posteriores.

Fishes from the Colombian Amazonia region: species composition from the river systems within the rainforest biome / Peces de la región de la Amazonía Colombiana: composición de especies de los sistemas fluviales del bioma de selva húmeda

Abstract The Colombian Amazon region is part of the Neotropical rainforest (humid forest biome) covering an area of 483,163 km2 and includes tributaries of both the Amazon and Orinoco River basins. The aquatic ecosystems found there include: rivers and alluvial plains originating in Andean headwaters, on eroded soils of tropical forests in the lowlands, and Guiana Shield formations, comprising a dense fluvial drainage network in the lowlands, with Paleogene/Neogene geological formations (terra firme streams in higher places that don't usually flood) and Paleozoic (shield streams); and Andean and Guiana Shield streams above 200-250 m a.s.l. We present here an exhaustive compilation of published information, supported by fish collections, consisting of a list of 1104 species distributed in 375 genera, 53 families, and 16 orders. We include occurrence data of these species in each sub-basin. The presence/absence species matrix was analyzed using a dendrogram and non-metric multidimensional scaling (NMDS) analysis to identify patterns of similarity between basins and sub-basins. We evaluated species composition between basins and among the different geological origins using PERMANOVA. The dendrogram shows co-occurrences of 404 species in the two basins. It also shows two clear groupings of the sub-basins of the Amazon (except Guainía-Negro drainages) and those of the Orinoco. Within the Amazon Basin, there are two nodes according to the geological origin: systems of Andean origin and those of the lowlands. The dendrogram results are consistent with the NMDS analysis, which shows a clear grouping according to the connectivity of the basins; the Guainía-Negro is included in the Amazon basin. Species distribution patterns were supported by the PERMANOVA, and differed significantly between basins (F = 4.3, R = 0.26, P = 0.003) and geological origin (F = 3.6, R = 0.23, P = 0.003). The number of species in this study represents almost a fifth of the ichthyofauna of the Neotropics and about a third of that of the Amazon River basin; clearly supporting Colombia's status among the countries with the greatest diversity of freshwater fish species of the planet. We include here a significant number of new records (75 spp), provide a first approximation of the distribution patterns, and a framework for future biogeographical studies.

Resumo La región de la Amazonía colombiana hace parte del bosque húmero neotropical (bioma de selva húmeda) abarcando un área de 483.163 km2 e incluye afluentes de las cuencas del Amazonas y Orinoco. Los ecosistemas acuáticos encontrados allí incluyen: ríos y llanuras aluviales, originándose en cabeceras andinas, en suelos erosionados de bosques tropicales en tierras bajas y en formaciones de escudos; conformando una densa red fluvial en tierras bajas con formaciones geológicas paleógenas-neógenas (arroyos de terra firme en sitios elevados que usualmente no se inundan) y paleozoicas (arroyos de escudo); y arroyos andinos y del escudo Guayanés por encima de 200-250 m s.n.m. Presentamos aquí una recopilación exhaustiva de información publicada, sustentada por colecciones ictiológicas, consistiendo en una lista de 1104 especies distribuidas en 375 géneros, 53 familias y 16 órdenes. Incluimos datos de estas especies en cada subcuenca. La matriz de presencia/ausencia de especies fue analizada usando un dendrograma y un análisis de escalamiento multidimensional no métrico (NMDS) para identificar patrones de similitud entre cuencas y subcuencas. Se evaluó la composición de especies entre cuencas y entre los diferentes orígenes geológicos usando PERMANOVA. El dendrograma refleja coocurrencia de 404 especies en las dos cuencas. También muestra dos agrupaciones claras de las subcuencas del Amazonas (excepto Guainía-Negro) y las del Orinoco. Dentro de la cuenca amazónica existen dos nodos según el origen geológico: los sistemas de origen andino y los de tierras bajas. Los resultados del dendrograma son consistentes con el análisis NMDS, el cual muestra una clara agrupación según la conectividad de las cuencas; el Guainía-Negro está incluido en la cuenca del Amazonas. Los patrones de distribución de especies fueron respaldados por el PERMANOVA y difirieron significativamente entre cuencas (F = 4.3, R = 0.26, P = 0.003) y origen geológico (F = 3.6, R = 0.23, P = 0.003). El número de especies en este estudio representa casi la quinta parte de la ictiofauna del Neotrópico y alrededor de un tercio de la de la cuenca del río Amazonas; soportando el estatus de Colombia entre los países con mayor diversidad de especies de peces de agua dulce del planeta. Incluimos aquí un número importante de nuevos registros (75 spp), brindamos una aproximación de los patrones de distribución y un marco para futuros estudios biogeográficos.

Overall distribution pattern of the intramuscular nerves of the extraocular muscles and its clinical implications / Patrón de distribución general de los nervios intramusculares de los músculos extraoculares y sus implicaciones clínicas

SUMMARY: The purpose of this study was to reveal the overall distribution pattern of the intramuscular nerves of each extraocular muscle and provide morphological guidance for the selection of the neuromuscular compartment during extraocular muscle transplantation and target localization of the botulinum toxin A injection to correct strabismus. We studied 12 Chinese head specimens that were fixed with formalin. The extraocular muscles from both sides of each head were removed, and a modified Sihler's staining technique was used to reveal the overall distribution pattern of the intramuscular nerves. We observed an intramuscular nerve-dense region formed by the intramuscular arborized branches in the semitransparent superior rectus, inferior rectus, medial rectus, lateral rectus, superior oblique, inferior oblique, and levator palpebrae superioris muscles with Sihler's staining technique. The seven extraocular muscles can each be divided into two neuromuscular compartments. The intramuscular nerve-dense regions of the superior, inferior, medial, and lateral rectus and the superior oblique, inferior oblique, and levator palpebrae superioris muscles were positioned at 33.50 % -72.72 %, 40.21 % - 66.79%, 37.92 % - 64.51 %, 31.69 % - 56.01 %, 26.35 % - 64.98 %, 40.46 % - 73.20 %, and 27.72 % - 66.07 % of the lengths of the muscle bellies, respectively, and the centers of intramuscular nerve dense regions were located at 59.50 %, 54.18 %, 51.68 %, 50.08 %, 48.38 %, 56.49 %, and 50.77 % of the length of each muscle belly, respectively. The aforementioned values are the means of the actual values. These results suggest that when the strabismus is corrected with muscle transplantation, the extraocular muscle should be transplanted based on the neuromuscular compartment, which would benefit the function of both donor and recipient muscles. The localization of these nerve dense regions is recommended as an optimal target for the injection of botulinum toxin A to treat strabismus.

RESUMEN: El objetivo de este estudio fue revelar el patrón de distribución de los nervios intramusculares de cada músculo extraocular y, proporcionar una guía morfológica para la selección del compartimento neuromuscular durante el trasplante de músculo extraocular, y la localización de la inyección de toxina botulínica A para corregir el estrabismo. Estudiamos 12 muestras de cabezas de individuos chinos fijadas en formalina. Se extrajeron los músculos extraoculares de ambos lados de cada cabeza y, se utilizó una técnica de tinción de Sihler modificada para revelar el patrón de distribución general de los nervios intramusculares. Observamos una región densa en nervios intramusculares formada por los ramos intramusculares en los músculos recto superior semitransparente, recto inferior, recto medial, recto lateral, oblicuo superior, oblicuo inferior y elevador del párpado superior con técnica de tinción de Sihler. Los siete músculos extraoculares se pueden dividir cada uno en dos compartimentos neuromusculares. Las regiones intramusculares densamente nerviosas de los músculos recto superior, inferior, medial y lateral y los músculos oblicuo superior, oblicuo inferior y elevador del párpado superior se colocaron en 33,50 % -72,72 %, 40,21 % -66,79 %, 37,92 % -64,51 % , 31,69 % -56,01 %, 26,35 % -64,98 %, 40,46 % -73,20 % y 27,72 % -66,07 % de las longitudes de los vientres musculares, respectivamente, y los centros de las regiones densamente nerviosas intramusculares se ubicaron en 59,50 %, 54,18 % , 51,68 %, 50,08 %, 48,38 %, 56,49 % y 50,77 % de la longitud de cada vientre muscular, respectivamente. Los valores antes mencionados son medios de los valores reales. Estos resultados sugieren que cuando el estrabismo se corrige con trasplante de músculo, el músculo extraocular debe trasplantarse en función del compartimento neuromuscular, lo que beneficiaría la función tanto de los músculos donantes como receptores. Se recomienda la localización de estas regiones densas en nervios, como un objetivo óptimo para la inyección de toxina botulínica A para tratar el estrabismo.

Prevalence, coincidence and distribution patterns of sesamoid bones of the hand / Patrones de prevalencia, coincidencia y distribución de los huesos sesamoideos de la mano

SUMMARY: The aim of this study is to identify the prevalence and distribution patterns of sesamoid bones at the metacarpophalangeal (MCP) and interphalangeal (IP) joints and to determine if there is an association between the distribution patterns and age, gender, and hand side. Patients who had a direct radiograph of the hand obtained between 2019-2020 were retrospectively evaluated. All radiographs were evaluated in terms of the prevalence, coincidence, and distribution patterns of sesamoid bones. Presence of an association between distribution patterns and age, sex and side was also assessed. A total of 1501 hand radiographs were included into the study. There were 12 different patterns of sesamoid bone distribution. The most common distribution pattern was the presence of sesamoid bone at the first MCP joint only (25.8 %). There was a positive correlation between the second and third MCP, second and fifth MCP, second and first IP, third and fourth MCP and fifth MCP and first IP joints. The pattern with a sesamoid bone at the first MCP joint only was more prevalent among males, whereas the pattern involving coincidence of sesamoid bones at the first, second, fifth MCP and first IP joints was more prevalent among females (p<0.001, p=0.031). A positive correlation was observed between age and the number of MCP joints with sesamoid bones (p<0.001). The number of MCP joints with sesamoid bones was found to be higher in females (p<0.001). This study is important in that it provided anatomical data that can be guiding for clinicians in terms of diagnosis and management of hand disorders.

RESUMEN: El objetivo de este estudio fue identificar la prevalencia y los patrones de distribución de los huesos sesamoideos en las articulaciones metacarpofalángicas (MCF) e interfalángicas (IF) y determinar si existe una asociación entre los patrones de distribución y la edad, el sexo y el lado de la mano; fueron evaluadas retrospectivamente radiografías de la mano obtenidas en 2019- 2020. Todas las radiografías se evaluaron en términos de prevalencia, coincidencia y patrones de distribución de los huesos sesamoideos. También se evaluó la presencia de una asociación entre los patrones de distribución y la edad, el sexo y el lado. Se incluyeron en el estudio un total de 1501 radiografías de mano. Se observaron 12 patrones diferentes de distribución de los huesos sesamoideos. El patrón de distribución más común fue la presencia de hueso sesamoideo solo en la primera articulación MCF (25,8 %). Hubo una correlación positiva entre la segunda y la tercera MCF, la segunda y la quinta MCP, la segunda y la primera IF, la tercera y cuarta MCF y la quinta MCF y las primeras articulaciones IF. El patrón con un hueso sesamoideo en la primera articulación MCF fue más prevalente entre los hombres, mientras que el patrón de coincidencia de los huesos sesamoideos en la primera, segunda, quinta articulación MCF y la primera articulación IF fue más prevalente entre las mujeres (p <0.001, p = 0,031). Se observó una correlación positiva entre la edad y el número de articulaciones MCF con huesos sesamoideos (p <0,001). El número de articulaciones MCF con huesos sesamoideos era mayor en las mujeres (p <0,001). Este estudio es importante debido a que proporcionó datos anatómicos que pueden ser una guía para los médicos en el diagnóstico y tratamiento de los trastornos de la mano.

The overall distribution pattern of the hand's cutaneous nerves and its clinical implications in sensory reconstruction / Patrón de distribución general de los nervios cutáneos de la mano y sus implicancias clínicas en la reconstrucción sensorial

SUMMARY: The objective of this study was to reveal the overall distribution pattern of the hand's cutaneous nerves to provide a morphological basis for the selection and matching of the hand skin for sensory reconstruction during flap transplantation. The hands of 12 adult cadavers were used for the study. Palmar region and dorsum of the hand were divided into regions I-VI. The skin of the hand containing subcutaneous fat was removed close to the muscle surface. The modified Sihler's staining method was used to visualize the overall distribution pattern of the cutaneous nerves and the areas they innervate. The median nerve, superficial branch of the ulnar nerve, and the superficial branch of the radial nerve innervated 59.27 % (containing 4.65 % of the palmar cutaneous branch of the median nerve), 36.91 %, and 3.82 % of the palm area, respectively. The superficial branch of the radial nerve, the dorsal branch of the ulnar nerve, and the median nerve innervated 45.16 %, 47.25 %, and 7.59 % of the hand's dorsal skin area, respectively. Communication was found between the arborized branches of these cutaneous nerves. Region III of the palm and region VI of the dorsum of the hand had relatively more dense nerve distribution. Except for region V, the density of the total nerve branches in each palm region was higher than that of the dorsum of the hand. The total number of nerve branches in the distal phalanx and dorsum decreased from the thumb to the digitus minimus. Our results provide morphological guidance when designing a reasonable matching flap to improve the hand's sensory function reconstruction.

RESUMEN: El objetivo de este estudio fue revelar el patrón de distribución general de los nervios cutáneos de la mano y proporcionar una base morfológica para la selección y adaptación de la piel de la mano, para la reconstrucción sensorial durante el trasplante de colgajo. Para el estudio se utilizaron 12 manos de cadáveres adultos. Las regiones palmar y dorsal se dividieron en regiones I-VI. La piel de la mano que contiene grasa subcutánea se eliminó cerca de la superficie del músculo. Para visualizar el patrón de distribución general de los nervios cutáneos y las áreas que inervan se utilizó el método de tinción de Sihler modificado. El nervio mediano, la rama superficial del nervio ulnar y la rama superficial del nervio radial inervaban el 59,27 % (que contenía el 4,65 % de la rama cutánea palmar del nervio mediano), el 36,91 % y el 3,82 % del área de la palma, respectivamente. La rama super-ficial del nervio radial, la rama dorsal del nervio ulnar y el nervio mediano inervaban el 45,16 %, el 47,25 % y el 7,59 % del área dorsal de la mano, respectivamente. Se observó comunicación entre las ramas arborizadas de estos nervios cutáneos. La región III de la palma y la región VI del dorso de la mano tenían una distribución nerviosa relativamente más densa. A excepción de la región V, la densidad de las ramas nerviosas totales en cada región de la palma fue mayor que el dorso de la mano. El número total de ramas nerviosas en la falange distal y el dorso disminuyó desde el pulgar hasta el dedo mínimo. Nuestros resultados proporcionan una guía morfológica al diseñar un colgajo compatible razonable para mejorar la reconstrucción de la función sensorial de la mano.

Megadiverse Ecuador: a review of Mysmenopsis (Araneae, Mysmenidae) of Ecuador, with the description of twenty-one new kleptoparasitic spider species.

The spider family Mysmenidae includes two genera in which kleptoparasitic species are known to occur, Isela and Mysmenopsis. Mysmenopsis is the most speciose with 31 species described so far. Herein, we describe twenty-one new species from Ecuador: M. alvaroi n. sp., M. amazonica n. sp., M. angamarca n. sp., M. awa n. sp., M. baerti n. sp., M. bartolozzii n. sp., M. choco n. sp., M. cube n. sp., M. corazon n. sp., M. guanza n. sp., M. guayaca n. sp., M. hunachi n. sp., M. junin n. sp., M. lasrocas n. sp., M. lloa n. sp., M. otokiki n. sp., M. pululahua n. sp., M. salazarae n. sp., M. shushufindi n. sp., M. tepuy n. sp. and M. tungurahua n. sp. We report for the first time the presence of four species of Mysmenopsis in the web of a Lycosidae, namely M. salazarae n. sp., M. shushufindi n. sp., M. bartolozzii n. sp. and M. amazonica n. sp. All new species described here were collected in spider webs either from the family Dipluridae (Linothele) or Lycosidae (Aglaoctenus) and therefore are assumed to be kleptoparasitic. New locality records are presented for M. otonga, M. fernandoi, M. atahualpa and M. penai, the female of M. penai is described for the first time. Maps of all Ecuadorian species are presented, kleptoparasitism, morphological characters and distribution of Mysmenopsis species are discussed.

Recommendation of the best site based on the distribution pattern of extramuscular and intramusular nerves for gluteal muscle injection / Recomendación del mejor sitio para la inyección del músculo glúteo basado en el patrón de distribución de los nervios extramusculares e intramusculares

To reveal the extra- and intramuscular nerve distribution patterns of the gluteus maximus, medius, and minimus, and to provide guidance for gluteal muscle injection in order to avoid nerve injury. Ten adult and 10 child cadavers were used. The superior and inferior gluteal nerves innervating the gluteus maximus, medius, and minimus were dissected, exposed, and sutured in-situ on the muscle. The three gluteal muscles were removed, and the distribution patterns of the intramuscular nerves were revealed by modified Sihler's nerve staining. The nerve distribution pattern was returned to the corresponding position in the body, and the patterns in the four quadrants of the buttock were analyzed. There were 3-12 extramuscular nerve branches of the gluteus maximus, medius, and minimus. After entering the muscle, these nerve branches arborized and anastomosed to form an arc-shaped, nerve-dense zone. The nerve distribution was most dense in the inferomedial region of the superolateral quadrant and the inferolateral region of the superomedial quadrant of the buttocks. The nerve distribution was relatively dense in the inferolateral region of the superolateral quadrant, and the medial region of the inferomedial quadrant. An arc-shaped, nerve-sparse zone in the superolateral and superomedial quadrants near the lower iliac crest accounted for about two-fifths of the two quadrants' limits. The arc-shaped, nerve-sparse zone in the superolateral quadrant is the preferred injection site, and the superomedial quadrant near the lower iliac crest is also recommended as a gluteal intramuscular injection region, free from nerve injury.

El objetivo de este trabajo fue revelar los patrones de distribución nerviosa extramusculat e intramuscular de los músculos glúteo máximo, medio y mínimo y proporcionar orientación para la inyección en la región glútea con el propósito de evitar lesiones nerviosas. Se utilizaron diez cadáveres adultos y diez niños. Los nervios glúteos superior e inferior que inervan a los músculos glúteo máximo, medio y mínimo fueron disecados, expuestos y suturados in situ en el músculo. Se extirparon los tres músculos glúteos y se revelaron los patrones de distribución de los nervios intramusculares mediante la tinción nerviosa de Sihler modificada. El patrón de distribución nerviosa se devolvió a la posición correspondiente en el cuerpo y se analizaron los patrones en los cuatro cuadrantes de la región glútea. Se encontraron 3 a 12 ramos nerviosos extramusculares de los músculos glúteo máximo, medio y mínimo. Después de ingresar al músculo, estas ramas nerviosas se arborizaron y anastomizaron para formar una zona densamente nerviosa en forma de arco. La distribución nerviosa fue de mayor densidad en la región inferomedial del cuadrante superolateral y en la región inferolateral del cuadrante superomedial de la región glútea. La distribución nerviosa era relativamente densa en la región inferolateral del cuadrante superolateral y en la región medial del cuadrante inferomedial. Una zona en forma de arco en los cuadrantes superolateral y superomedial y con escasa inervación, cerca de la cresta ilíaca representaba una parte de los límites de los dos cuadrantes. La zona de poca inervación en forma de arco en el cuadrante superolateral es el sitio de inyección preferido, y el cuadrante superomedial próximo a la cresta ilíaca también se recomienda como una región de inyección intramuscular glútea, libre de lesión nerviosa.

Atmospheric PM2.5 Mercury in the Metropolitan Area of Mexico City.

In this study, atmospheric mercury concentration in airborne particulate matter with an aerodynamic diameter ≤ 2.5 µm (PM2.5) was analyzed by ICP-MS. Samples were collected in the Mexico City Metropolitan Area (MCMA), during 2013, in five locations, Northwest, Northeast (NE), Central, Southwest and Southeast, along three seasons: dry warm, rainy, and dry cold (DC). It can be observed that NE shows the highest mercury concentration (p < 0.05), where pollution events were identified. The seasonal distribution shows that samples collected during DC present the highest concentration (p < 0.05). These results are in agreement with the distribution of important mercury industrial sources located in the northern urban area as well with the temperature and wind conditions during 2013. The comparison of data obtained in this work with those of similar previous studies clearly indicates a decrease, between 2006 and 2013, of mercury content in PM2.5 collected in MCMA.

Recognition of the importance of geogenic sources in the content of metals in PM2.5 collected in the Mexico City Metropolitan Area.

The study of airborne metals in urban areas is relevant due to their toxic effects on human health and organisms. In this study, we analyzed metals including rare earth elements (REE) in particles smaller than 2.5 µm (PM2.5), collected at five sites around the Mexico City Metropolitan Area (MCMA), during three periods in 2011: April (dry-warm season, DW), August (rainy season, R), and November (dry-cold season, DC). Principal component analysis allowed identifying factors related to geogenic sources and factors related to anthropogenic sources. The recognition of the high impact of geogenic sources in PM2.5 is in agreement with the REE distribution patterns, which show similar behavior as those shown by igneous rocks, confirming the influence of the regional geogenic material. Metals associated to geogenic sources showed higher concentration (p < 0.05) at NE of the MCMA and a significant correlation with prevalent winds. Geogenic metals show similar seasonal distribution, with the highest concentration during DW (p < 0.05), suggesting a possible metal resuspension effect which affects more significantly at lower relative humidity (RH). The metals associated with anthropogenic sources are in agreement with the urban complexity of the area, showing homogenous distribution throughout MCMA (p > 0.05) and no similar seasonal pattern among them. These unexpected results exposed outstanding information regarding the identification of different geogenic sources as the main contributors of metals in the atmospheric environment in the MCMA and highlighted the importance of meteorology in the spatial and seasonal metal patterns.

Predictors of Arbuscular Mycorrhizal Fungal Communities in the Brazilian Tropical Dry Forest.

Arbuscular mycorrhizal fungi (AMF) are symbiotic fungi with a broad distribution, and many taxa have physiological and ecological adaptations to specific environments, including semiarid ecosystems. Our aim was to address regional distribution patterns of AMF communities in such semiarid environments based on spore morphological techniques. We assessed AMF spores at the bottom and top of inselbergs distributed throughout the tropical dry forest in the Northeast region of Brazil. Across 10 replicate inselbergs and the surrounding area, spanning a range of altitude between 140 and 2000 m, we scored the AMF soil diversity and properties in 52 plots. We fitted parsimonious ordination analyses and variance partitioning models to determine the environmental factors which explained the variation in AMF community, based on morphological spore analysis. The diversity of AMF was similar at the bottom and top of inselbergs; however, we detected high variation in abundance and richness across sites. We formulated a parsimonious richness model that used physical soil factors as predictors. The AMF community structure could be best explained through the variables coarse and total sand, iron, organic matter, potassium, silt, and sodium which together accounted for 17.8% of total variance. Several AMF species were indicators of either deficiency or high values of specific soil properties. We demonstrated that habitat isolation of the inselbergs compared with surrounding areas did not trigger differences in AMF communities in semiarid regions of Brazil. At the regional scale, soil predictors across sites drove the distribution of symbiotic mycorrhizal fungi.

Large-scale migration of a school shark, Galeorhinus galeus, in the Southwestern Atlantic

Knowledge of the spatial and temporal distribution patterns of chondrichthyans is critical for their effective management. In this study we report and analyze a large-scale latitudinal migration (~ 1,425 km) of a female school shark in the Southwestern Atlantic shelf where it is currently classified as Critically Endangered. During the austral summer (February 15, 2015), ninety-four school sharks were captured (75 females and 19 males) and tagged with fin tags in Nuevo Gulf (~ 42°43'S, 64°53'W, Argentina). A female of 112 cm total length was recaptured in Uruguayan shelf waters in the austral winter (August 17, 2015). This long displacement represents the first direct evidence to support Vooren and Lucifora's hypothesis of a single transnational population of Galeorhinus galeus in the Southwestern Atlantic. The good agreement found between the school shark habitat conditions (salinity 33-34, temperature 12-17°C) and the warmer member of Subantarctic Shelf Waters suggests that the seasonal variation in school shark abundance within this region could be related to water masses movements.(AU)

El conocimiento sobre los patrones de distribución espacio-temporal de los condrictios es crítico para su manejo efectivo. En este trabajo presentamos y analizamos una migración latitudinal de gran escala (~ 1.425 km) de una hembra de cazón en la plataforma del Océano Atlántico Sudoccidental, donde está actualmente clasificada como Críticamente en Peligro. Durante el verano austral (15 de Febrero de 2015), 94 cazones fueron capturados (75 hembras y 19 machos) y señalados con marcas "rotatag" en el Golfo Nuevo (~ 42°43'S, 64°53'W, Argentina). Una hembra de 112 cm de longitud total fue recapturada en aguas de la plataforma uruguaya durante el invierno austral (17 de Agosto de 2015). Este gran desplazamiento representa la primera evidencia directa para apoyar la hipótesis de Vooren y Lucifora sobre una única población transnacional de Galeorhinus galeus en el Océano Atlántico Sudoccidental. La gran coincidencia encontrada entre las condiciones de hábitat para el cazón (salinidad 33-34, temperatura 12-17° C) y el integrante más cálido del Agua de Plataforma Subantártica sugiere que la variación estacional en la abundancia del cazón dentro de esta región podría estar relacionada con el movimiento de las masas de agua.(AU)

Large-scale migration of a school shark, Galeorhinus galeus, in the Southwestern Atlantic

Knowledge of the spatial and temporal distribution patterns of chondrichthyans is critical for their effective management. In this study we report and analyze a large-scale latitudinal migration (~ 1,425 km) of a female school shark in the Southwestern Atlantic shelf where it is currently classified as Critically Endangered. During the austral summer (February 15, 2015), ninety-four school sharks were captured (75 females and 19 males) and tagged with fin tags in Nuevo Gulf (~ 42°43'S, 64°53'W, Argentina). A female of 112 cm total length was recaptured in Uruguayan shelf waters in the austral winter (August 17, 2015). This long displacement represents the first direct evidence to support Vooren and Lucifora's hypothesis of a single transnational population of Galeorhinus galeus in the Southwestern Atlantic. The good agreement found between the school shark habitat conditions (salinity 33-34, temperature 12-17°C) and the warmer member of Subantarctic Shelf Waters suggests that the seasonal variation in school shark abundance within this region could be related to water masses movements.(AU)

El conocimiento sobre los patrones de distribución espacio-temporal de los condrictios es crítico para su manejo efectivo. En este trabajo presentamos y analizamos una migración latitudinal de gran escala (~ 1.425 km) de una hembra de cazón en la plataforma del Océano Atlántico Sudoccidental, donde está actualmente clasificada como Críticamente en Peligro. Durante el verano austral (15 de Febrero de 2015), 94 cazones fueron capturados (75 hembras y 19 machos) y señalados con marcas "rotatag" en el Golfo Nuevo (~ 42°43'S, 64°53'W, Argentina). Una hembra de 112 cm de longitud total fue recapturada en aguas de la plataforma uruguaya durante el invierno austral (17 de Agosto de 2015). Este gran desplazamiento representa la primera evidencia directa para apoyar la hipótesis de Vooren y Lucifora sobre una única población transnacional de Galeorhinus galeus en el Océano Atlántico Sudoccidental. La gran coincidencia encontrada entre las condiciones de hábitat para el cazón (salinidad 33-34, temperatura 12-17° C) y el integrante más cálido del Agua de Plataforma Subantártica sugiere que la variación estacional en la abundancia del cazón dentro de esta región podría estar relacionada con el movimiento de las masas de agua.(AU)

Determining Clostridium difficile intra-taxa diversity by mining multilocus sequence typing databases.

BACKGROUND: Multilocus sequence typing (MLST) is a highly discriminatory typing strategy; it is reproducible and scalable. There is a MLST scheme for Clostridium difficile (CD), a gram positive bacillus causing different pathologies of the gastrointestinal tract. This work was aimed at describing the frequency of sequence types (STs) and Clades (C) reported and evalute the intra-taxa diversity in the CD MLST database (CD-MLST-db) using an MLSA approach. RESULTS: Analysis of 1778 available isolates showed that clade 1 (C1) was the most frequent worldwide (57.7%), followed by C2 (29.1%). Regarding sequence types (STs), it was found that ST-1, belonging to C2, was the most frequent. The isolates analysed came from 17 countries, mostly from the United Kingdom (UK) (1541 STs, 87.0%). The diversity of the seven housekeeping genes in the MLST scheme was evaluated, and alleles from the profiles (STs), for identifying CD population structure. It was found that adk and atpA are conserved genes allowing a limited amount of clusters to be discriminated; however, different genes such as drx, glyA and particularly sodA showed high diversity indexes and grouped CD populations in many clusters, suggesting that these genes' contribution to CD typing should be revised. It was identified that CD STs reported to date have a mostly clonal population structure with foreseen events of recombination; however, one group of STs was not assigned to a clade being highly different containing at least nine well-supported clusters, suggesting a greater amount of clades for CD. CONCLUSIONS: This study shows the usefulness of CD-MLST-db as a tool for studying CD distribution and population structure, identifying the need for reviewing the usefulness of sodA as housekeeping gene within the MLST scheme and suggesting the existence of a greater amount of CD clades. The study also shows the plausible exchange of genetic material between STs, contributing towards intra-taxa genetic diversity.

Plant zonation in a tropical irregular estuary: can large occurrence zones be explained by a tradeoff model? / Zonação vegetal em um estuário tropical irregular: amplas zonas de ocorrência podem ser explicadas por um modelo tradeoff?

AbstractEstuaries present an environmental gradient that ranges from almost fresh water conditions to almost marine conditions. Salinity and flooding are the main abiotic drivers for plants. Therefore, plant zonation in estuaries is closely related to the tidal cycles. It is expected that the competitive abilities of plants would be inversely related to the tolerance toward environmental stress (tradeoff). Thus, in estuaries, plant zonation tends to be controlled by the environment near the sandbar and by competition away from it. This zonation pattern has been proposed for regular non-tropical estuaries. For tropical estuaries, the relative importance of rain is higher, and it is not clear to what extent this model can be extrapolated. We measured the tidal influence along the environmental gradient of a tropical irregular estuary and quantified the relative importance of the environment and the co-occurrence degree. Contrary to the narrow occurrence zone that would be expected for regular estuaries, plants presented large occurrence zones. However, the relative importance of the environment and competition followed the same patterns proposed for regular estuaries. The environmental conditions allow plants to occur in larger zones, but these zones arise from smaller and infrequent patches distributed across a larger area, and most species populations are concentrated in relatively narrow zones. Thus, we concluded that the zonation pattern in the Massaguaçu River estuary agrees with the tradeoff model.

ResumoEstuários apresentam um gradiente ambiental que varia de condições próximas a de água doce a condições quase marinhas. A salinidade e o alagamento são os principais fatores abióticos para as plantas. Por isso, a zonação vegetal em estuários está proximamente relacionada aos ciclos da maré. É esperado que as habilidades competitivas das plantas sejam inversamente relacionadas à tolerância ao estresse ambiental (tradeoff). Assim, em estuários, a zonação vegetal tende a ser controlada pelo ambiente, próximo à barra, e pela competição, longe da mesma. Esse padrão de zonação tem sido proposto para estuários regulares não tropicais. Para estuários tropicais, a importância relativa da chuva é maior, e não é claro até que ponto esse modelo pode ser extrapolado. Nós medimos a influência da maré ao longo do gradiente ambiental de um estuário tropical irregular e quantificamos a importância relativa do ambiente e o grau de correlação. Contrariamente à ocorrência estreita que seria esperada para estuários regulares, as plantas apresentaram amplas zonas de ocorrência. No entanto, a importância relativa do ambiente e da competição seguiram os mesmos padrões propostos para estuários regulares. As condições ambientais permitem às plantas ocorrerem em zonas mais amplas, mas estas zonas resultam de pontos ocasionais, e as populações da maioria das espécies estão concentradas em zonas relativamente estreitas. Desse modo, concluímos que o padrão de zonação no estuário do Rio Massaguaçu está de acordo com o modelo tradeoff.

Plant zonation in a tropical irregular estuary: can large occurrence zones be explained by a tradeoff model? / Zonação vegetal em um estuário tropical irregular: amplas zonas de ocorrência podem ser explicadas por um modelo tradeoff?

Estuaries present an environmental gradient that ranges from almost fresh water conditions to almost marine conditions. Salinity and flooding are the main abiotic drivers for plants. Therefore, plant zonation in estuaries is closely related to the tidal cycles. It is expected that the competitive abilities of plants would be inversely related to the tolerance toward environmental stress (tradeoff). Thus, in estuaries, plant zonation tends to be controlled by the environment near the sandbar and by competition away from it. This zonation pattern has been proposed for regular non-tropical estuaries. For tropical estuaries, the relative importance of rain is higher, and it is not clear to what extent this model can be extrapolated. We measured the tidal influence along the environmental gradient of a tropical irregular estuary and quantified the relative importance of the environment and the co-occurrence degree. Contrary to the narrow occurrence zone that would be expected for regular estuaries, plants presented large occurrence zones. However, the relative importance of the environment and competition followed the same patterns proposed for regular estuaries. The environmental conditions allow plants to occur in larger zones, but these zones arise from smaller and infrequent patches distributed across a larger area, and most species populations are concentrated in relatively narrow zones. Thus, we concluded that the zonation pattern in the Massaguaçu River estuary agrees with the tradeoff model.(AU)

Estuários apresentam um gradiente ambiental que varia de condições próximas a de água doce a condições quase marinhas. A salinidade e o alagamento são os principais fatores abióticos para as plantas. Por isso, a zonação vegetal em estuários está proximamente relacionada aos ciclos da maré. É esperado que as habilidades competitivas das plantas sejam inversamente relacionadas à tolerância ao estresse ambiental (tradeoff). Assim, em estuários, a zonação vegetal tende a ser controlada pelo ambiente, próximo à barra, e pela competição, longe da mesma. Esse padrão de zonação tem sido proposto para estuários regulares não tropicais. Para estuários tropicais, a importância relativa da chuva é maior, e não é claro até que ponto esse modelo pode ser extrapolado. Nós medimos a influência da maré ao longo do gradiente ambiental de um estuário tropical irregular e quantificamos a importância relativa do ambiente e o grau de correlação. Contrariamente à ocorrência estreita que seria esperada para estuários regulares, as plantas apresentaram amplas zonas de ocorrência. No entanto, a importância relativa do ambiente e da competição seguiram os mesmos padrões propostos para estuários regulares. As condições ambientais permitem às plantas ocorrerem em zonas mais amplas, mas estas zonas resultam de pontos ocasionais, e as populações da maioria das espécies estão concentradas em zonas relativamente estreitas. Desse modo, concluímos que o padrão de zonação no estuário do Rio Massaguaçu está de acordo com o modelo tradeoff.(AU)

Conservation of mayflies (Insecta, Ephemeroptera) in Espírito Santo, southeastern Brazil

Conservation of mayflies (Insecta, Ephemeroptera) in Espírito Santo, southeastern Brazil. Ephemeroptera exhibits great diversity among bodies of freshwater in the Atlantic Forest, a biome that is suffering from massive human impact. Within this context, the creation of conservation units using biological information is more recommended than economic, cultural, or political criteria. The distribution pattern of 76 Ephemeroptera species was analyzed using the biogeographical methods Parsimony Analysis of Endemicity and Network Analysis Method in order to infer relevant areas for conservation of the mayfly community in Espírito Santo. The results obtained from both analyses were largely congruent, and pointed out four relevant areas for conservation: two in the south of the state, where conservation units or priority areas for conservation are well established; and two in the north, a region in the state where little conservation efforts have been historically done. Therefore, based on our analyses on mayflies, we recommend the expansion of the existing APCs or the creation of new APCs on the north of Espírito Santo.

Seasonal pattern of Chrysomelidae (Coleoptera) in the state of Paraná, southern Brazil / Padrão sazonal de Chrysomelidae (Coleoptera) no estado do Paraná, sul do Brasil

The aim of this paper was to describe the seasonal patterns of Chrysomelidae and of its most abundant species at eight sites in different geomorphological and floristic regions in the state of Paraná, southern Brazil. Samples with Malaise traps, from August 1986 to July 1988 were performed. The Chrysomelidae showed seasonal patterns with the highest abundance in the spring and/or summer at all sites, but with variations in the months of highest captures. Photoperiod was the variable that most influenced the seasonality of Chrysomelidae, and along with temperature and relative humidity, determined most of the seasonal patterns of the family at the different sites. Some dominant species of Chrysomelidae showed different seasonal pattern compared to the family level. A better knowledge of the seasonal distribution patterns of these species will only be possible when their life history, such as host plants and behavior, was better understood.

O objetivo deste estudo foi descrever os padrões de sazonalidade de Chrysomelidae e de suas espécies dominantes, capturadas em oito locais de diferentes regiões geomorfológicas e florísticas do estado do Paraná, sul do Brasil. As coletas foram realizadas com armadilha Malaise de agosto/1986 a julho/1988. Chrysomelidae apresentou padrão sazonal com picos de abundância na primavera e/ou verão em todos os locais, mas com variações quanto aos meses de maior captura. O fotoperíodo foi a variável com maior influência na sazonalidade de Chrysomelidae e juntamente com a temperatura e umidade relativa, determinaram a maioria dos padrões sazonais da família nos diferentes locais. Algumas das espécies dominantes de Chrysomelidae apresentaram padrão sazonal distinto do observado para a família. O entendimento dos padrões de distribuição das espécies de Chrysomelidae somente será possível quando informações sobre a história de vida, como plantas hospedeiras e comportamento, forem melhor esclarecidas.

Lebiasina yepezi, a new Lebiasininae (Characiformes: Lebiasinidae) from the Serra Parima-Tapirapecó mountains

Lebiasina yepezi, a new Lebiasininae with a conspicuous color pattern, is described. The new species is endemic of the headwaters of the rio Negro, rio Branco, and rio Orinoco in the Serra Parima-Tapirapecó Mountains, at the border of Brazil and Venezuela. The new species is readily distinguished from all other Lebiasininae by the presence of four black longitudinal stripes on the trunk, and the triangular shaped dorsal surface of the mesethmoid, lacking lateral projections. The unusual color pattern is contrasted with those of other lebiasinin, as well as members of the pyrrhulinin genus Nannostomus. A close relationship between Lebiasina yepezi and the Gran Sabana (Venezuela) species is suggested based in color pattern features. The present contribution corresponds to a further refutation of the type locality of L. intermedia, as suggested on its description, since Lebiasinins, except L. bimaculata, L. boruca, and L. festae, do not occur in low land waters.

Lebiasina yepezi, um novo Lebiasininae com um conspícuo padrão de colorido, é descrito. A nova espécie é endêmica das cabeceiras do rio Negro, rio Branco e rio Orinoco, na Serra Parima-Tapirapecó, ao longo da fronteira entre Brasil e Venezuela. A nova espécie é prontamente diferenciada das demais espécies pela presença de quatro faixas longitudinais escuras ao longo do corpo, e a superfície dorsal do mesetmoide com o formato triangular, não apresentando projeções laterais. O padrão de colorido incomum é comparado com o dos demais Lebiasininae e também com o dos Pyrrhulininae do gênero Nannostomus. Uma próxima relação é proposta entre Lebiasina yepezi e as espécies da Gran Sabana (Venezuela) com base em caracteres de colorido. A presente contribuição corresponde a mais uma refutação da localidade-tipo de L. intermedia conforme sugerida na descrição daquela espécie, uma vez que os lebiasiníneos, com exceção de L. bimaculata, L. boruca e L. festae, não ocorrem em rios de terras baixas.