|  | site | site # (info) | collection date | kind | depth | substrate | salin | comments | reference | 
| A | Black Sea (Chernoe More, Chernoye More, Euxine Sea, Schwarzes Meer, Schwarzen Meeres) | 83 
  map | 1906 or earlier | default type |  |  |  |  | Bohmig L (1906): abstract | 
| B | Mediterranean Sea  (Mittelmeer) | 82 
  map | 1989 or earlier |  |  |  |  | Mittelmeer, Schwarzes Meer, Ostatlantik (Plymouth, England).  'P. plebeia occurs in brackish water springs or in otherwise brackish habitats' (Sluys 1989b, p. 288) | Sluys R (1989): from Ax 2008 (citation)- 295 | 
| C | Black Sea (Chernoe More, Chernoye More, Euxine Sea, Schwarzes Meer, Schwarzen Meeres) | 83 
  map | 1989 or earlier |  |  |  |  | Mittelmeer, Schwarzes Meer, Ostatlantik (Plymouth, England).  'P. plebeia occurs in brackish water springs or in otherwise brackish habitats' (Sluys 1989b, p. 288) | Sluys R (1989): from Ax 2008 (citation)- 295 | 
| D | Plymouth, England (English Channel) | 255 
  map | 1989 or earlier |  |  |  |  | Mittelmeer, Schwarzes Meer, Ostatlantik (Plymouth, England).  'P. plebeia occurs in brackish water springs or in otherwise brackish habitats' (Sluys 1989b, p. 288) | Sluys R (1989): from Ax 2008 (citation)- 295 | 
| E | Sandgerdhi, Reykjanes Peninsula, Iceland | 6313 
  map | Aug 1999 |  |  |  |  |  | Sluys R, Kawakatsu M (2005): 462 | 
| F | Plymouth, England (English Channel) | 255 
  map | 1968 or earlier | default type |  |  |  |  | den Hartog C (1968): from Ball & Reynoldson 1981 (citation)- p. 46 |