Observations on the Sphingidae (Lepidoptera) of Trinidad

Abstract

AbstractSpecies records of Sphingidae taken in Trinidad were kept from 1968 to 1979. Seventy–five species and one subspecies were taken, including several new records for the island. The numbers of sphingids taken in Robinson light–traps equipped with 125–watt mercury–arc lamps were recorded over a period of eight years at St. Augustine, Trinidad, and the data analysed. The species abundance distribution was found to be well–fitted by the log–normal series. Data were examined for trends and periodicities, and the variance was found to be largely accounted for by three principal factors. A long–term decline in catch was observed in one trap due to the growth of screening vegetation. Annual variation in catch was found to correlate with the annual pattern of precipitation, with higher catches during the rainy season, although some species differences were detectable. Monthly variation in catch was found to correspond with the cycle of lunar illumination, being significantly depressed with increasing brightness. Interspecific differences in the response to moonlight were also detected. The influence of screening effects on the observed periodicities is discussed in relation to the siting of the traps. Times of commencement of flight activity were recorded, and the relationship between time of capture and activity is discussed. Apart from one species, the sex ratio of captured sphingids was significantly male-biased. Data from three traps were compared with each other and with those from other tropical locations.