|  | site | site # (info) | collection date | kind | depth | substrate | salin | comments | reference | 
| A | Capo Posillipo (Cap Posilipo), Bay of Naples, Italy | 4364 
  map | Mar-Apr 1958 |  | 3 m | shell, sand |  | Neapel: Capo Posilipo; grober Bruchschill ohne Sand. | Ax P, Weidemann E, Ehlers B (1978): 115 | 
| B | Helgoland, Germany | 4234 
  map | 1938 or earlier | default type | 2-4 m | shell |  | Helgoland: südlich der Nordspitze der Insel; mittelgrober Schill. | Meixner J (1938): ; from Ax, Weidemann & Ehlers (citation)- p. 120 | 
| C | Helgoland, Germany | 4234 
  map | Aug 1964 | default type | 2-4 m | shell |  | Helgoland: südlich der Nordspitze der Insel; mittelgrober Schill. | Ax P, Weidemann E, Ehlers B (1978): 120 |