Issue No. 338
G. B. Edwards
January, 1991
Introduction
Metaltella simoni (Keyserling) is a relatively recent introduction to the Florida spider fauna. Although it is generally inconspicuous, M. simoni may be a threat to extirpate the Florida population of our native amaurobiid species.
Originally known from Argentina, southern Brasil, and Uruguay, M. simoni was subsequently imported into the southern United States. The first known record for this species in the U.S. is 23-30 July 1944, from Harahan, Louisiana. The most recent revision of North American Amaurobiidae (Leech 1972) gives the following known U.S. records (by county): Florida (Bay County); Louisiana (East Baton Rouge, Orleans, and St. Tammany Parishes); and Mississippi (Jackson and Pearl River Counties). The published Florida record is from St. Andrews State Park, 28 March 1966, 2 females collected by J. A Beatty, under board in open sandy area at edge of woods. A second, previously unpublished, Florida record is from Liberty County, Torreya State Park, 7 June 1977, 1 male collected by J. A Beatty (personal communication, J. A Beatty).
The Florida State Collection of Arthropods (FSCA) presently has 30 separate collections of M. simoni from Florida. Most of these records are from Gainesville in Alachua County. The earliest such collection is 22 February 1981, 1 female taken by G. B. Edwards in a web under pine bark; the most recent collection is 28 August 1986, 1 male found by G. B. Edwards wandering inside a building. Many of the Gainesville records are from the Doyle Conner Building prior to the initiation of a regular fumigation program.
A few records exist in Florida south of Alachua County. A female M. simoni was collected in Orange County, Lake Buena Vista, 3 February 1982, by J. Atwood, in a shipment of Jacaranda acutifolia Humb. & Bonpl. plants from California. As no records of this spider are known from California, it is likely that the spider entered the shipment after it arrived in Florida. Three juvenile specimens which appear to be M. simoni have also been found. A penultimate male was captured in Volusia County, Samsula, 4 February 1980, by J. N. Pott, on Draceana sp. An immature female was collected in Brevard County, Titusville, 22 February 1986, by A Baker. Another penultimate male was found in Lee County, Alva, 28 August 1981, by C. Scharfenberg, on pothos, Epipremnum aureum (Linden & Andre) Bunt.
Recent surveys of arachnid populations from various Florida plant communities (e.g., Corey and Taylor, 1988, 1989; Corey et al. 1991) have been useful for recording the presence of particular species. Florida records for M. simoni collected by D. T. Corey are as follows: 1 female, Suwannee County, Suwannee River State Park, 1 May 1987; 1 female, Alachua County, Gainesville, 10 July 1987; 5 males, 1 female, Polk County, Lake Wales, 14 November 1986; 1 female, also from Lake Wales, 11 November 1987. All of these specimens were taken from pitfall traps.
Based on the above records, it appears that M. simoni has spread steadily eastward and southward into Florida since it was first collected in the state in 1966. Its synanthropic habits are well documented by its frequent occurrence in buildings and, to a lesser extent, on ornamental plants. However, several records of feral individuals indicate that it is equally at home away from human habitations. Leech (1972) noted that M. simoni is quite common in Mississippi and parts of Louisiana in the wild.