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Management, brood nest structure and factors associated with varroa mites infestation were studied in 60 apiaries of Africanized honey bees in the northwest region of the Central Valley of Costa Rica. Apiaries were monitored two times. The first monitoring was taken forward between May and November 2019 (rainy season) and the second one between February and March 2020 (dry season). Information about the beekeepers, apiaries and management was collected through a survey. Amount of open and capped brood, honey and pollen were registered. The infestation rate of varroa was measured using standard laboratory methods. A determination of multi-residue pesticides in bee bread was made through GC-MS/MS and LC-MS/MS techniques. According to the results, most of the beekeepers produce honey (96.7%), participate in training activities (82.2%), and change the bee queens annually (70.0%). The first monitoring was characterized by a lower amount of capped brood and honey reserves than the second one. Varroa mites infestation was significantly higher in the first monitoring (6.0 ± 0.4) in comparison with the second one (3.0 ± 0.3) (U Mann-Whitney p < 0.001). The maximum value for the first monitoring exceeds 40.0%, while this value was close to 25.0% in the second monitoring. Mite infestation had direct correlations with the distance of near apiaries and the presence of perforated capping brood, while it had inverse correlations with the nuclei formation and training activities. Furthermore, twenty-three bee bread samples presented one to five pesticide residues, being the most frequent antifungal agrochemicals.

Resumen Introducción. La Nosemosis es una enfermedad de las abejas melíferas, que se encuentra diseminada por todo el mundo y ocasiona pérdidas económicas. Es causada por 2 especies de hongos, Nosemaapis y Nosemaceranae. Objetivo. Se determinó la cantidad de esporas de Nosemaspp. en muestras grupales e individuales de abejas, y se relacionaron con la precipitación y humedad. Materiales y métodos. El estudio se realizó de julio a noviembre 2017, en 10 colmenas de abejas africanizadas en Atenas, Alajuela. De cada colmena, se colectaron 100 abejas, para examinarlas en el laboratorio de Patología Apícola-CINAT. Para el análisis grupal, se cortaron los abdómenes de 30 abejas y se maceraron con 30 ml de agua destilada. La muestra se revisó en el microscopio a 40x y se cuantificaron las esporas de Nosemaspp. mediante el hemocitómetro. Para el examen individual, se utilizó la misma técnica. La precipitación y humedad relativa durante el estudio, se relacionaron con el número de esporas. Resultados y conclusión. Se detectó el microsporidio Nosemaspp. en todas las colmenas analizadas. En julio, se cuantificó el mayor número de esporas, con un promedio de 20 360 000 ± 1 586 957 en el análisis grupal y 12 749 733 ± 867 232 en el individual. En los meses siguientes se observó un descenso en el conteo de esporas en ambos métodos, hasta contabilizar la menor cantidad en noviembre, con un promedio de 4 375 000 ± 874 132 y 2 087 708 ± 398 895 en el examen grupal e individual, respectivamente. Al relacionar la precipitación y humedad con la cantidad de esporas, setiembre presentó la mayor cantidad de lluvia y un alto porcentaje de humedad, sin embargo, no correspondió con el mayor nivel de Nosemosis, el cual se registró en julio. Mientras que noviembre fue el menos lluvioso y húmedo, y mostró la menor cantidad de esporas. Abstract Introduction. Nosemosis is the most wide spread of adult honeybee diseases that cause significant economic losses worlwide. Honeybees are parasitized by 2 fungus species, Nosemaapis and Nosemaceranae. Objective. The amount of spores of Nosema spp. in group and individual samples of adult bees was related with precipitation and relative humidity conditions.Materials and methods.This study was conducted from July to November 2017, in 10 africanized honeybees colonies in Atenas, Alajuela. A 100 foragers bees were collected per colony to examine them at the Bee Pathology Labof CINAT. For the group analysis, the abdomens of thirty adult bees were cut and macerated together in 30 ml of distilled water. Nosema spp. Spores were identified using a light microscopy at 40x magnification and counted with the hemocytometer. For the individual analysis, the same method was used. Precipitation and relative humidity conditions during the study period were related with the amount of Nosema spp. spores. Results and conclusion. The microsporidium Nosema spp. Was found in all colonies. In July, the highest number of Nosema spores were quantified, with anaverage of 20 360 000 ± 1 586 957 per bee in groupanalysis and 12 749 733 ± 867 232 in individual analysis. In thefollowingmonths a decrease in the number of spores was observed and the lowest amount of spores was recorded in November, with anaverage of 4 375 000 ± 874 132 and 2 087 708 ± 398 895 ofspores in group and individual exam, respectively. When relating the conditions of precipitation and humidity with the amount of spores, September presented the highest amount of rain and a high percentage of humidity, nevertheless, it did not correspond to the highest infection level of Nosema spp., which occurred in July. Meanwhile, November was the leastrainy and humid month and in turn presented the least amount of spores.

El primer reporte sobre la presencia del Pequeño Escarabajo de la Colmena (PEC), Aethina tumida, en Costa Rica, se realizó el 25 de agosto 2015, en La Cruz, Guanacaste; lo cual aumenta el riesgo de dispersión a otras zonas apícolas del país. Por tanto, para este estudio, se realizó un muestreo de mayo a octubre del 2019. Se analizó 305 colmenas, distribuidas en 61 apiarios, ubicados en San Ramón, Alajuela. Adicionalmente, se examinó muestras de escarabajos adultos provenientes de Ulloa, Heredia y de Potrerillos de Liberia, Guanacaste. En cada apiario se analizó, aleatoriamente, cinco colmenas. Se revisó la tapa, los marcos, las cajas y el piso, con el fin de identificar la presencia de huevos, larvas y/o adultos del escarabajo. También, para reconocer algún signo relacionado, como galerías en los panales, apariencia húmeda de las abejas, entre otros. Las muestras de escarabajos adultos se analizaron en el laboratorio de Patología Apícola del CINAT-UNA. Las 305 colmenas evaluadas, en San Ramón de Alajuela, resultaron negativas para el Pequeño Escarabajo. Por otra parte, se confirmó la presencia de A. tumida en una colonia establecida en una casa de habitación en Ulloa, Heredia; también, en un apiario ubicado en Potrerillos de Liberia, el cual se encuentra aproximadamente a 25 km del foco inicial en La Cruz, Guanacaste. Con base en lo expuesto, se puede indicar la presencia de A. tumida en colmenas de abejas africanizadas en diferentes zonas de Costa Rica, con una distribución limitada. Al considerar que el escarabajo adulto puede volar y desplazarse, junto a enjambres silvestres; además, la trashumancia de colmenas por parte del apicultor, se debe mantener una revisión periódica de los apiarios, dado que las condiciones actuales de ausencia, en la mayoría de colmenas analizadas en este estudio, pueden cambiar. The first report of Small Hive Beetles (SHB), Aethina tumida, in Costa Rica was made on August 25, 2015, in La Cruz, Guanacaste, which increased the risk of dispersal to other beekeeping areas in the country. Therefore, in this study 305 colonies belonging to 61 apiaries, located in San Ramón, Alajuela, Costa Rica, were sampled from May to October 2019. In addition, adult beetle samples were analyzed from Ulloa, Heredia and Potrerillos, Liberia, Guanacaste. Five colonies were randomly selected in every apiary. Broods, boxes, combs, and bottom boards were checked for beetle eggs, larvae and/or adults, and for any related signs such as galleries in the combs, and wet appearance of bees, among others. Adult beetles were analyzed at the Bee Pathology Lab of the Tropical Beekeeping Research Center (CINAT-UNA). The 305 colonies evaluated in San Ramón tested negative for SHBs. On the other hand, the presence of A. tumida was confirmed in a wild colony in a house located in Ulloa, Heredia and in an apiary in Potrerillos, Liberia, which is approximately 25 km from the initial beetle focus in La Cruz, Guanacaste. Based on the above, the presence of A. tumida can be confirmed in Africanized honey bee colonies in different beekeeping areas of Costa Rica, with a limited distribution. Given that adult SHB can fly and move with wild swarms and the transhumance of colonies by beekeepers, apiaries must be periodically checked because the current absence in most of the colonies analyzed in the present study can change. Universidad Nacional, Costa Rica Centro de Investigaciones Apícolas Tropicales

Se estudió la prevalencia del microsporidio Nosema spp. en un apiario de 10 colmenas de abejas africanizadas en Atenas-Alajuela, Costa Rica, durante julio a noviembre 2017. Además, se comparó el número de esporas y el nivel de infección en muestras grupales e individuales de abejas adultas provenientes de una misma colmena. Se muestreó el apiario con un intervalo de 30 días. De cada colmena se colectaron aproximadamente 100 abejas adultas de la piquera, de las cuales 30 se examinaron de manera grupal y 30 individualmente en el Laboratorio de Patología Apícola-CINAT. Para determinar las esporas de Nosema spp. las abejas se analizaron mediante el método de Cantwell. Para el análisis grupal, se tomaron 30 abejas y se procedió a cortar los abdómenes, los cuales se maceraron en un mortero, agregando 30 ml de agua destilada. En el examen individual, se utilizó la misma técnica y se analizó cada abeja por separado. La muestra se revisó en el microscopio a un aumento de 40x, se procedió a identificar y determinar el número de esporas mediante el hemocitómetro y a establecer el nivel de infección de cada colmena. Se determinó la presencia de Nosema spp. en todas las colmenas del apiario, pero con diferentes niveles de infección, variando desde leve hasta fuerte, tanto en el análisis grupal como en el individual. En julio se cuantificó el mayor número de esporas, con un promedio de 20,360,000 ± 1,586,957 por abeja en el examen grupal y 12,749,733 ± 867,232 por abeja en el individual. En los meses siguientes se observó un descenso considerable en el número de esporas, hasta contabilizar la menor cantidad en noviembre, con un promedio de 4,375,000 ± 874,132 y 2,087,708 ± 398,895 para los análisis grupal e individual, respectivamente. Al comparar el conteo de esporas y el nivel de infección de Nosema spp. en muestras grupales e individuales, se obtuvieron resultados similares. Además, al correlacionar la cantidad de esporas se estableció una alta proximidad en los valores, mostrando que mediante ambos métodos se obtiene un resultado semejante en el nivel de infección de la misma colmena. The prevalence of the microsporidium Nosema spp. was studied during the rainy months from July to November 2017 in 10 Africanized honeybees colonies in Atenas-Alajuela, Costa Rica. In addition, the number of spores and the infection level were compared in group and individual samples of adult bees from the same colony. The apiary was sampled once a month. Approximately 100 forager bees per colony were collected, of which 30 were examined for Nosema spp. in group analysis and 30 individually at the Bee Pathology Lab-CINAT. According to the Cantwell method, the abdomens of 30 adult bees were cut and macerated together with 30 ml of distilled water for the group test. For the individual analysis, the same method was used, but each bee was examined separately. Nosema spores were identified under the cover slip using a light microscopy at 40x magnification and were counted with a hemocytometer. The infection level was determined for every colony. The microsporidium Nosema spp. were found in all apiary colonies at different levels, ranging from low to severe infection in both group and individual exams. In July, the highest number of Nosema spores were quantified, with an average of 20,360,000 ± 1,586,957 per bee in the group analysis, and 12,749,733 ± 867,232 per bee in the individual analysis. In the following months, a considerable decrease in the number of spores was observed, and the lowest amount was recorded in November, with an average of 4,375,000 ± 874,132 and 2,087,708 ± 398,895 spores per bee in the group and individual exam, respectively. When comparing the spore count and the infection level of Nosema spp. in group and individual samples, similar results were obtained. Furthermore, by correlating the number of spores, high proximity in the values was found, showing that, by both methods, a similar result is obtained concerning the infection level of the same colony. A prevalência do microsporídio Nosema spp. foi estudado durante os meses de julho a novembro de 2017, em 10 colmeia de abelhas africanizadas em Atenas-Alajuela, Costa Rica. Além disso, o número de esporos e o nível de infecção foram comparados em grupos e amostras individuais de abelhas adultas da mesma colmeia. Realizaram-se amostragens do apiário com um intervalo de 30 dias. Em cada colmeia, foram coletadas aproximadamente 100 abelhas adultas, das quais 30 foram examinadas em análise de grupo e 30 individualmente, no Laboratório de Patologia Apícola-CINAT. Para determinar os esporos de Nosema spp. as abelhas foram analisadas pelo método de Cantwell. Para a análise do grupo, foram retiradas 30 abelhas cujos abdomens foram cortados e macerados, acrescentando-se 30 ml de água destilada. Para a análise individual, o mesmo método foi usado, mas cada abelha foi examinada separadamente. A amostra foi analisada ao microscópio com aumento de 40x. O número de esporos foi identificado e determinado com o hemocitômetro e o nível de infecção em cada colmeia foi estabelecido. O microsporídio Nosema spp. foi encontrado em todas as colmeias do apiário, em diferentes níveis de infeccção, variando de leve a forte, tanto nas análises grupais como nas individuais. Em julho, foi quantificado o maior número de esporos, com uma média de 20.360.000 ± 1.586.957 por abelha na análise de grupo e 12.749.733 ± 867.232 por abelha, no individual. Nos meses seguintes, observou-se uma diminuição considerável no número de esporos, sendo a menor quantidade registrada em novembro, com uma média de 4.375.000 ± 874.132 e 2.087.708 ± 398.895 esporos por abelha para análises grupais e individuais, respectivamente. Ao comparar a contagem de esporos e o nível de infecção de Nosema spp. em grupos e amostras individuais, resultados semelhantes foram obtidos. Além disso, ao correlacionar o número de esporos, encontrou-se uma alta proximidade nos valores, mostrando que, por ambos métodos, um resultado semelhante é obtido em relação ao nível de infecção da mesma colmeia. Universidad Nacional, Costa Rica Centro de Investigaciones Apícolas Tropicales

Dos especies nuevas de Phlegmariurus Holub, P. gracilis A. Rojas y P. nanus A. Rojas & R. Calderón, son descritas aquí. Ellas pertenecen al complejo P. reflexus. La primera se caracteriza por hojas en verticilos alternos de 4 o 5 y estas con el margen entero o dispersa y cortamente dentado. La segunda corresponde a un taxón con tallos bastante pequeños (6–11 cm de largo) y simples a 1–dicotomos, y las hojas con cilios largos y dispersos marginalmente.

On 26 September 1997, Varroa jacobsoni was detected in samples of brood and adult bees of three colonies from the Los Santos region of Costa Rica. Since no acaricides are registered for veterinary use in Costa Rica, the National University's Centre for Research on Tropical Bees (CINAT) and the Ministry of Agriculture are trying to fight the mite with formic acid.