50 Differentiation L. obtusata/L. fabalis.

50 Differentiation L. obtusata/L. fabalis.

Citrina juvenile Littorina fabalis from semi exposed shore (Ballantine 4). No adult L. obtusata found on beach. Has thin shell, typical of juvenile. Assumed to be L. fabalis; has pure white intial “spirorbid” whorls usually confined to some L. fabalis. But no adults found had citrina shell with well developed “spirorbid” whorls.
Shell height 5mm. Llŷn, North Wales. September 2015.
Full account at: 02 Differentiation L. obtusata/L. fabalis

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