Notes on the Biology of Aspisoma Ignitum (L.) (Coleoptera: Lampyridae): A New Firefly Record for Puerto Rico

Abstract

During the early hours of clear nights of December 1983 and January 1984 one of us (JASB) noticed many firefly flashes over an old field at Bayam6n, Puerto Rico where the vegetation consisted mostly of Gramineae and Leguminosae bushes rarely higher than 1.5 m. Flashes had not been seen there in previous years. For several nights during January 1984 JASB and several neighborhood boys collected more than 30 fireflies in less than 90 minutes. Comparison with specimens in the collection of the University of Puerto Rico, Agricultural Experiment Station, Rio Piedras and perusal of pertinent literature (Maldonado-Capriles and Navarro 1967, Medina-Gaud and Garcia-Tuduri 1977, Medina-Gaud and Martorell 1973, Wolcott 1948) suggested that the species was a new record for the island. Dr. J. Ramos, (University of Puerto Rico, Mayagez) identified the firefly as Aspisoma ignitum (L.) (Fig. 1). This identification was confirmed by Dr. J. E. Lloyd (University of Florida, Gainesville, FL). The presence of this insect constitutes a new genus and species for the Puerto Rican entomofauna. With this firefly, a total of 12 lampyrids are known for Puerto Rico (Wolcott 1948). The total length of the collected specimens ranges from 11.5 to 15 mm making this one of the largest lampyrids known for the island. Females were slightly longer than males (Y ? X = 13.7 mm, sd = 0.8, n = 9; d d X = 12.8 mm, sd = 0.7 mm, n = 36). Aspisoma ignitum can be distinguished from all other known fireflies of Puerto Rico by its color pattern: dull green, pronotum with yellow areas; elytra with eight longitudinal yellow lines and a short yellow band (about 2-3 x 1 mm) close to the anteroretrolateral area. The sexes can be distinguished by the ventral coloration of abdominal segments V-VII: males are bright yellow (Fig. 2), females have wide brown areas (Fig. 3). In addition, there are morphological differences on the margin of abdominal segment VII: on males there is a wide terminal concavity (Fig. 4) while females have a deep indentation (Fig. 5). Flashing was first noticed at about 18:45 (30-60 minutes after sunset) and ceased about 19:30-20:00. Flying specimens seldom exceeded an altitude of about 3 m.; this observation agrees with that reported for San Andres Is. (West Indies) by Farnworth (1969). These fireflies are relatively easy to capture because of their slow flight. Most of the individuals collected during the night were males and undoubtedly in this species, as in others, flying males locate stationary females (Lloyd 1971).