Urbanus simplicius (Stoll, 1790) is a frequently encountered Neotropical skipper butterfly, ranging from northern Argentina through South and Central America to southern Texas, USA (Evans 1952; Rickard 1977), where it appears to be a non-established stray from Mexico (Neck 1996; a single record also exists for California, see Tilden 1976). Its distribution extends from South America into the Caribbean on Trinidad and Tobago, where the species is locally abundant (Evans 1952; Cock 1982, 1986; Smith et al. 1994), and a single record exists for the Windward Islands, from Grenada (Smith et al. 1994). Throughout its range, U. simplicius is commonly found in disturbed habitats of many types, as well as undisturbed tropical forest. The larval foodplants for U. simplicius are herbaceous legumes (Fabaceae), including Tipuana tipu (Benth.) Kuntze in Brazil (Silva et al. 1968), Phaseolus vulgaris L. in Argentina (Hayward 1969; also in California, see Tilden 1976), Glycine max (L.) Merr. in Uruguay (Biezanko et al. 1974), Puearia phaseoloides (Roxb.) Benth. on Trinidad (Cock 1986), and species of Arachis L., Calopogonium Desv., Centrosema (DC.) Benth., Desmodium Desv., Galactia P. Browne, Phaseolus L., Rhynchosia Lour., Teramnus P. Browne and Vigna Savi in Costa Rica (Janzen & Hallwachs 2011).
As reported by Smith et al. (1994), U. simplicius has been known from Grenada by a single female specimen collected in February 1986, at St. Paul, St. George Parish. They speculated that the individual was likely a stray from Trinidad or Tobago. Urbanus simplicius was not found on Grenada during a brief survey in 1995 (Cock 2002), and we are unaware of other captures of this species on Grenada before 2011.
On 20 September 2011, during field activities for a Lepidoptera Identification Workshop held 19–23 September 2011 at the Windward Islands Research and Education Foundation (WINDREF) on the campus of St. Georges University, St. Georges, Grenada, the first two authors collected seven males and two females of Urbanus simplicius at Progress Park in St. Andrew Parish (N12 08.033 W61 37.176), a disturbed habitat about forty feet above sea level (Figure 1). Progress Park is south of Pearls Airport and about 1 km west of the coastline of Great River Bay. The park is an agricultural area with small fields, some of which were overgrown with Guinea Grass, Panicum maximum Jacq., and some which were being used as cultivated plots with various vegetables. There were a few houses in the vicinity. The specimens of U. simplicius represent 35% (> 1/3) of the total number of hesperiid specimens collected that day. Given the local abundance of U. simplicius in St. Andrew Parish, we believe the species to be an established breeding resident on Grenada. We urge field workers on Grenada to monitor the distribution and abundance of this species on the island, and to determine local larval foodplants.
We thank the sponsors of the Lepidoptera Identification Workshop, the Florida Association for Volunteer Action in the Caribbean and the Americas (FAVACA), the Inter-American Institute for Cooperation in Agriculture (IICA), and the United States Department of Agriculture (USDA) for their assistance in making the workshop a success, and the participants for their assistance with collecting.