Methods for collecting large numbers of exuviae from Coptotermes (Blattodea: Rhinotermitidae) termite colonies

The nutritional properties of subterranean termite exuviae (shed exoskeletons) are not well-known because obtaining the large quantities necessary for investigation is difficult. A method for collecting large numbers of exuviae is reported here for the Asian subterranean termite, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae), an invasive and economically important tropical termite species. In this study, groups of 1,000 C. gestroi workers from 4-yr-old laboratory colonies (n = 3) were allowed to feed on a media pad dyed with Nile Blue A for 2 d. Approximately 16% of the original 1,000 workers did not uptake dye. These individuals were then placed into a Petri dish with dyed filter paper and checked hourly (10:00 A.M. to 10:00 P.M.) for 7 d. Newly molted workers and those individuals that started turning blue were removed to prevent feeding on exuviae. An average of 14 workers molted per d that yielded an average of 12 exuviae with an overall mean of 86 exuviae collected over the 7 d study period. We also found the number of individuals that acquired dye during the study significantly decreased by d. However, variables such as the number of exuviae, newly molted individuals, and cadavers were not correlated with d of collection because termites molt asynchronously. Resumen Las propiedades nutricionales de las exuviae de termitas subterraneas (exoesqueletos desprendidos) no son bien conocidas porque es dificil de obtener las grandes cantidades necesarias para su investigacion. Aqui se informa un metodo para recolectar grandes cantidades de exuvias para la termita subterranea asiatica, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae), una especie de termita tropical invasora y economicamente importante. En este estudio, se permitio que grupos de 1,000 trabajadores de C. gestroi de colonias de laboratorio de 4 anos de edad (n = 3) se alimentaran de una almohadilla de medio tenida con Azul Nilo A durante 2 dias. Aproximadamente el 16% de los 1,000 trabajadores originales no tomaron tinte. A continuacion, estos individuos se colocaron en un plato Petri con papel de filtro tenido y se controlaron cada hora (10:00 A. M. a 10:00 P. M.) durante 7 dias. Los trabajadores recien mudados y los individuos que comenzaron a ponerse azules fueron retirados para evitar alimentarse de las exuvias. Un promedio de 14 trabajadores mudaron por dia, lo que produjo un promedio de 12 exuvias con una media general de 86 exuvias recolectadas durante el periodo de estudio de 7 dias. Tambien encontramos que el numero de individuos que adquirieron tinte durante el estudio disminuyo significativamente por dia. Sin embargo, las variables como el numero de exuvias, los individuos recien mudados y los cadaveres no se correlacionaron con los dias de recoleccion porque las termitas mudan asincronicamente. Key Words: Coptotermes gestroi; ecdysis; exoskeleton; molting; dye; histological stains View this article in BioOne