Scapteriscus vicinus

Abstract: The first successful inoculative releases of an entomopathogenic nematode, Steinernema scapterisci Nguyen and Smart, for the control of exotic pests, Scapteriscus spp. mole crickets, were made at three pasture sites in Alachua County, Florida in 1985. Based on the evaluation of field-collected crickets, the nematode was established at all sites and persisted for over 5 years. Mean yearly percentage of infected crickets ranged from 0 to 21.4% for individual release sites. Mean adult infection level for all years combined, 10.9%, was significantly greater than that for nymphs (2.5%) and infection levels for Scapteriscus borellii Giglio-Tos, 12.7%, was significantly greater than that for Scapteriscus vicinus Scudder (4.5%) for all years combined. Although 24 h trap catch results indicate mole cricket populations were significantly reduced, the nematode's effect on pest abundance could not be adequately assessed because of the variation in trap catch results and inadequate knowledge about the relationship bet...

Abstract: Neither of the mole crickets most damaging to turf, pastures, and crops in southeastern United States is taxonomically what it has been thought to be. Scapteriscus vicinus Scudder, also called “changa” or “Puerto Rican mole cricket,” is distinct in calling song and interdactyl distance from the species known by the same name in Puerto Rico. Therefore its introduction at Brunswick, GA, ca. 1899, was from some other source. By 1960 its U.S. distribution included all of Florida, southern Georgia, and southernmost South Carolina. No additional spread has been reported during the past 20 years. Scapteriscus acletus Rehn and Hebard, long believed native to southeastern United States, was introduced at Brunswick, Georgia, ca. 1904. It was apparently introduced anew at Charleston, SC (ca. 1915), Mobile, AL (ca. 1919), and Port Arthur, TX (ca. 1925). Variations in pronotal color patterns suggest that the Charleston and Port Arthur introductions had a different origin than the Brunswick and Mobile introductions. By 1960, acletus had spread throughout Florida and southern Georgia, as far north as southern North Carolina, and as far west as eastern Louisiana; it had also occupied a large disjunct area in western Louisiana and eastern Texas. It has since spread to central Louisiana and been collected at scattered localities northward. Neither S. vicinus nor S. acletus reached peninsular Florida prior to 1925, but Scapteriscus abbreviatus Scudder, a flightless species of minor pest status, was introduced at six coastal cities of peninsular Florida, as well as at Brunswick, Georgia, prior to 1925. The homelands of U.S. Scapteriscus spp. should be located and their pathogens, parasites, and predators studied as potential biological control agents.

Abstract: Greenhouse studies of mole cricket tunneling architecture were conducted with adult southern, Scapteriscus borellii Giglio-Tos and tawny, Scapteriscus vicinus Scudder, mole crickets exposed to Beauveria bassiana (Balsamo) Vuillemin. Three different strains of B. bassiana as well as the commercially available insecticide Talstar (bifenthrin) were evaluated for avoidance behaviors by examining tunneling characteristics. Each treated container was inspected 24 h after treatment for specific tunneling behaviors in association with the presence of a control agent and the cricket’s response to the conidia or chemical. One of the B. bassiana strains tested, DB-2, caused changes in mole cricket behavior, including significantly less new surface tunneling, fewer vertical tunnels descending into the soil, less tunneling along the perimeter of the containers, and significantly more occurrences of the crickets remaining in an area that reduced exposure to the conidia. Two of the other treatments, strain 10-2...

Abstract: The behavior of mole crickets, serious pests of turfgrass, is poorly understood and has been rarely studied, predominantly because these insects dwell deep in the soil and are highly mobile. To better understand how the tawny mole cricket, Scapteriscus vicinus Scudder, and the southern mole cricket, S. borellii Giglio-Tos, behave in the soil, we used nondestructive x-ray techniques and wax and fiberglass resin castings to study the tunneling patterns and interactions of these mole crickets with their environment. Both species typically constructed Y-shaped tunnels to facilitate feeding and escape routes. Herbivorous tawny mole crickets tended to have more extensive and deeper tunnel systems than predatory southern mole crickets. Mole crickets maintained Y-shaped tunnels when subsoil density increased but often bent or terminated tunnels to avoid compacted areas. Both species maintained separate tunnels in the presence of other individuals of the same species. However, southern mole crickets exhibited more extreme separation, suggesting an avoidance behavior that may have been mediated by chemical, vibrational, or auditory cues. Although tawny mole crickets did not alter the shape of their Y-shaped tunnels in the presence of southern mole crickets, they sometimes would wall-off a tunnel, presumably in defense. Tawny mole crickets avoided contact with the entomopathogenic fungi, Beauveria bassiana (Balsamo) and Metarhizium anisopliae (Melchnikoff). This behavior suggests the potential of finding biologically active compounds that inhibit soil insect movement and could be used in the management of soil insect pests.