The Geography of a Southern Bug

Southeastern Geographer Vol. XIX, No. 2, November 1979, pp. 103-113 THE GEOGRAPHY OF A SOUTHERN RUG* Robert H. Fuson and Dewey M. Stowers,Jr. INTRODUCTION. Plecia nearctica Hardy (Díptera: Ribionidae) is a very small bug that lives in the southern United States. Its scientific name was given in 1940 by D. E. Hardy, who was the first to describe the insect. (J ) Refore Hardy's definitive work, P. nearctica was referred to as Plecia bicolor Rellardi, and was known colloquially as the "honeymoon fly." (2) Sometime after 1940, and perhaps as late as the 1960s, the insect acquired the name "lovebug" (Fig. 1). Unless you are an entomologist, or have lived or traveled in the Humid Subtropical Coastal Region, it is unlikely that you have ever seen the species. In May and September, however, the southern coastal lowlands from Texas to South Carolina are inundated by billions of lovebugs . It is during these months that the entomologists lose their exclusive claim to P. nearctica, for the little insect affects the economic system of the region, interferes with leisure activities, is attacked verbally by officials ofthe National Safety Council and the American Automobile Association, and has even stimulated political debates. ORIGIN AND HABITAT. Although a proper name has now been assigned , and "lovebug" has become a widely recognized nickname, there is still some doubt as to the origin of the insect. P. nearctica may or may not be a native Southerner. Ruschman (in 1975) stated that Hetrick (in 1970) said the bug was "native to the Southeast." (3) Hetrick, on the other hand, never made such a claim. (4) Part of the problem appears to arise because the lovebug (P. nearctica), known to have been in Loui- * The writers wish to thank the following entomologists for their assistance: Ron Anderson (Mississippi State University), H. R. Burke (Texas A&M University ), Joan Chapín (Louisiana State University), W. H. Darden (University of Alabama), J. C. Morse (Clemson University), G. J. Musick (University of Georgia ), and D. L. Stephan (North Carolina State University). Special thanks go to Skip Stowers for providing the photographs. Dr. Fuson is Professor and Chairman, and Dr. Stowers is Associate Professor , both in the Department ofGeography, University ofSouth Florida, Tampa, FL 33620. 104SOUTHEASTERN GEOGRAPHER Fig. 1. A male lovebug (left) and female lovebug (right) in copula. siana since 1911, is often confused with Plecia americana Hardy, and vice versa. (5) P. americana, which superficially resembles the lovebug, is clearly a native inhabitant of the southeastern woodlands and was collected in Florida as early as 1888. (6) Unlike the lovebug, however, P. americana emerges only once a year (spring), causes little concern because of its low population, and appears stabilized in a balanced ecosystem. The lovebug, in contrast to its woodland cousin, prefers a grassland habitat, emerges in the spring and fall (though it has been collected in every month except November), exhibits explosive population tendencies that impinge upon human activities, and is presently beyond any environmental controls. (7) All of the lovebug's behavioral patterns suggest that it is an invader to the coast east of Louisiana. It may have come to Louisiana and Texas from Mexico and Central America around the Vol. XIX, No. 2 105 Fig. 2. The migration ?? Plecia nearctica: 1911-1975. turn of the century, or it may have diffused west and south from Louisiana about that time. MIGRATION. The lovebug has an annual flight range ofapproximately 32 km. (8) Despite this extensive flight ability, humans may have contributed to its migration. (9) The eastward movement from Louisiana closely approximates the coming of the automobile to the Gulf coast. Today millions of the species hitch rides along southern highways; this practice probably began when the first gasoline-powered vehicle plowed through a lovebug swarm. Also, sod is frequently moved in the South, and this is a natural habitat of the larvae. Ry 1949 the lovebug had migrated or been transported to the western Florida panhandle (Fig. 2). (JO) Here the eastward trek stalled and P. nearctica settled down in the grassy lowlands between Pensacola and Panama City for a decade. The most likely reason for the sluggish advance during that time was a combination of...