Invasion

Invasion Description

1st Record: Philadelphia/PA/Delaware River (Richards 1929),

1st Record: Wilson Bridge (Prince Georges County)/MD/Potomac River (1960, Dundee 1974)

,

1st Record: Jones Point Lighthouse, Alexandria/Potomac River- Specimens were collected at Jones Point Lighthouse, Alexandria VA, 1960 (United States National Museum of Natural History Collection) and from '1/4 mile below Woodrow Wilson Bridge' (Academy of Natural Sciences of Philadelphia collection, no date, Dundee 1974)

Geographic Extent

Philadelphia/PA/Delaware River (Richards 1929),

; Susquehanna River State Park (Havre de Grace)/MD/Susquehanna River (tidal) ((2000, Fofonoff, personal observations); Wilson Bridge (Prince Georges County)/MD/Potomac River (1960, Dundee 1974); Jones Point (Alexandria)/VA/Potomac River (Dundee 1974);; Dyke Marsh (Alexandria)/VA/Potomac River (1997, Fofonoff, personal observations); Richmond/VA/Westhampton Lake, James River tributary (10/31/2017, USGS Nonindigenous Aquatic Species Program 2017). Not found in recent collections from the Ptomac River Ryan 2015; (Bocxlaer and Strong 2016; Fowler et 2022).

,

Jones Point Lighthouse, Alexandria/Potomac River- Specimens were collected at Jones Point Lighthouse, Alexandria VA, 1960 (United States National Museum of Natural History Collection) and from '1/4 mile below Woodrow Wilson Bridge' (Academy of Natural Sciences of Philadelphia collection, no date, Dundee 1974). Several dead shells were found at Dyke Marsh, Alexandria VA, 1997-2000 (Fofonoff personal observation). Live snails were found on blocks anchoring settling plates near a powerplant in Alexandria in 1999. (Ruiz et al., unpublished data). In an informal collection of shells but C. chinensis and Heterogen. aponica were found (Fofonoff, personal observation), but a detailed study of the snails would be needed to determine the relative abundance and distribution of the two species.  However, recent genetic surveys could not distinguish two species (Ryan 2015), or found only H. japonica japonica (Fowler et al. 2023)

James River- Bellamya chinensis was collected in 2017 in Westhampton Lake, Richmond VA, near the James River (USGS Nonindigenous Aquatic Species Program 2017).