Arizona: Xenopus laevis was intentionally introduced into man-made ponds in Arthur Park Golf Course, Tucson, Pima County, Arizona, in the 1960s (Tinsley and McCoid, 1996). Other X. laevis were released into man-made bodies of water in southern Arizona by the same individual (Tinsley and McCoid, 1996). D. Swann (personal communication 1997) also has observed X. laevis in golf course ponds in Tucson.
California: In California, X. laevis were first collected from several localities in Orange County (Westminster, East Garden Grove-Winterburg Channel, Slater Lake, Fountain Valley [Ocean View Channel and an associated lake], and Greenfield-Banning Channel southeast of the Santa Ana River) in the late 1960s through the early 1970s (Lenaker, 1972; St. Amant and Hoover, 1973; Bury and Luckenbach, 1976; Tinsley and McCoid, 1996). Additional specimens were collected in Irvine, Orange County, in 1989 (Tinsley and McCoid, 1996). Since it was first introduced to California, X. laevis has been found in the following counties: San Bernardino County (Prado Basin, Chino Hills State Park) (Stebbins, 2003; B. Goodman in Crayon 2005; Stebbins and McGinnis, 2012), San Diego County (Sweetwater [west Mt. Helix area], San Diego, Otay, Rancho Jamul, and Tijuana Rivers, Tecolote and Dulzura Creeks, and Spring Valley) (Bury and Luckenbach, 1976; Stebbins, 1985, 2003; Tinsley and McCoid, 1996; Kuperman et al., 2004; Stebbins and McGinnis, 2012; output from California Academy of Sciences), Santa Barbara County (Goleta Slough) (Stebbins, 2003; S. Sweet in Crayon, 2005; Stebbins and McGinnis, 2012), Los Angeles County (Santa Clara River, Munz Lake, Palmdale, Upper Rio Hondo, Compton Creek, Vasquez Rocks County Park, Edwards Air Force Base [Piute Ponds], and ponds and streams in Soledad, Agua Dulce and Placerita Canyons) (Bury and Luckenbach, 1976; Stebbins, 1985, 2003; Tinsley and McCoid, 1996; Stebbins and McGinnis, 2012; output from California Academy of Sciences), Riverside County (Arroyo Seco Creek and surrounding ponds, Santa Margarita River drainage, Santa Ana River, Vail Lake, and Riverside city) (McCoid and Fritts, 1980, 1989; Stebbins, 1985, 2003; Tinsley and McCoid, 1996; Kuperman et al., 2004), Imperial County (irrigation canals) (Stebbins, 1985; Stebbins and McGinnis, 2012), Kern County (Edwards Air Force Base) (Stebbins, 2003; Stebbins and McGinnis, 2012), San Francisco County (Lily Pond in Golden Gate Park, San Francisco) (E. Mills in Lagos, 2004), Ventura County (Santa Clara River and estuary, and Vern Freeman Diversion at Saticoy) (Lafferty and Page, 1997; output from California Academy of Sciences), and Yolo County (University of California Davis campus) (Tinsley and McCoid, 1996; Stebbins, 2003; Stebbins and McGinnis, 2012).
Colorado: In June 1990, a single X. laevis was found under a submerged log in a relic beaver pond associated with the North Fork of the Snake River, Summit County, Colorado (Bacchus et al., 1993; Tinsley and McCoid, 1996; Livo et al., 1998). The water was partially frozen and slushy (Bacchus et al., 1993).
Florida: In 1964, about 200 African Clawed Frogs were released into Hialeah (Red Road) Canal, Hialeah, Mimi-Dade County, Florida, by an animal importer (King and Krakauer, 1966). An additional Florida record includes a single X. laevis found near Tampa, Hillsborough County, with no date of collection or voucher recorded (Tinsley and McCoid, 1996), although S. Godley (personal communication 2014), M. McCoid (personal communication 2014), and R. McDiarmid (personal communication 2014) state the specimen was collected sometime during the mid-1970s and give the locality as Riverview, which is in the Tampa Bay area. This specimen has since been lost (R. McDiarmid, personal communication 2014; H. Mushinsky, personal communication 2014). In December 2013 and January 2014 two more X. laevis (UF-Herpetology 172054-55) were collected in Riverview, and a third from the same location on 10 June 2014 (UF-Herpetology 173050). On 27 June 2010 at 1430 h, an adult X. laevis was collected and vouchered (UF 158477, MorphoBank M88444) while dip-netting in a retention pond on Knox McRae Drive, 0.08 km east of Sussana Lane, Titusville, Brevard County, Florida (Krysko et al., 2011; Dodd, 2013). On 9 August 2014, an adult X. laevis (UF-Herpetology 173224 [FWC 47425]) was collected at 19251 SW 318 Terrace, Homestead, Miami-Dade County.
Massachusetts: Newly transformed X. laevis were collected from a small pond at the Acton Arboretum, Acton, Middlesex County, Massachusetts, in 1993 (Cardoza et al., 1993).
North Carolina: A population of X. laevis existed in fish hatchery ponds at an unknown locality in North Carolina during an unspecified period of time (Tinsley and McCoid, 1996). This is probably the same population cited by McCoid (in McCoid and Kleberg, 1995).
Virginia: A nonindigenous population of X. laevis was first observed in an artificial pond in a nature preserve (unnamed) in Virginia, "south of Washington, D.C.," in 1982 and sampled by R. Tinsley in 1987 (Tinsley and McCoid, 1996). Afterwards, local conservation personnel systematically collected hundreds of adults and juveniles (Tinsley and McCoid, 1996). Ernst et al. (1997) mention 30 recently transformed X. laevis collected from a pond at the Gulf Branch Nature Center, Arlington, Arlington County, between 15 May and 30 June 1984 (C. Ernst, personal communication 1997). These probably represent the same population mentioned by Tinsley and McCoid (1996).
Wisconsin: In 1972, a "large number" of late-stage larval X. laevis were collected from an artificial pond in Greenfield Park, Milwaukee, Milwaukee County, Wisconsin (Tinsley and McCoid, 1996).
Other U.S. western states: African Clawed Frogs are "rumored" to occur in Nevada, New Mexico, Utah, and Wyoming (Smith and Kohler, 1978). Perhaps these are the other unnamed states vaguely alluded to by Tinsley and McCoid (1996). Xenopus laevis has been collected from an undisclosed locality in Texas (Dixon, 2013).
Mexico: Nonindigenous X. laevis have spread into Baja California, Mexico, through the Tijuana River and intersecting irrigation canals from California (Murphy, 1983; Tinsley and McCoid, 1996; Peralta-García et al., 2014).
Chile: Nonindigenous African clawed frogs were first reported in Chile in 1985 (Tinsley and McCoid, 1996), although their original introduction may have taken place as early as 1973 (Jaksic, 1998). Additional specimens were captured on land with Sherman traps, in the Santiago area, in 2001 (Lobos and Garín, 2002). Xenopus laevis has since spread into IV Region (Limari River Basin), VI Region, and throughout Metropolitan Region, and V Region (Lobos and Jaksic, 2005).
Atlantic: Nonindigenous X. laevis were collected from Ascension Island in the southern Atlantic, in 1944 and 1958, near the summit of Green Mountain (Loveridge, 1959). Additional X. laevis were observed in a mountaintop pond (probably from the same aforementioned population) in the early 1980s (Tinsley and McCoid, 1996).
Europe: Xenopus laevis specimens have been collected in the Hamburg area, Germany, and Gorichem and Utrecht, the Netherlands (Tinsley and McCoid, 1996; Rabitsch et al., 2013), France, Italy (Sicily) (Fouquet, 2001; Lillo et al., 2005; Eggert and Fouquet, 2006; Fouquet and Measey, 2006; Faraone et al., 2008; Kraus, 2009; Measey et al., 2012), Sweden, Portugal, and Spain (Rebelo et al., 2010; Mateo et al., 2011; Measey et al., 2012). Additional X. laevis were released in Germany by animal rights activists in the 1990s. In the United Kingdom, populations of X. laevis have been found on the Isle of Wight, southern Wales, London, Kent (East Sussex border), Humberside (Scunthorpe), and various southwestern waterways in England (Arnold, 1995; Tinsley and McCoid, 1996; Arnold and Ovenden, 2002; Measey et al., 2012; Tinsley et al., 2012).
Japan: African Clawed Frogs have been collected from various localities in Japan (Kraus, 2009; Measey et al., 2012).
Israel: A single individual was recorded in Emek Hefer, Israel, in 1996 (Measey et al., 2012).
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