1: Severn Estuary, Gloucestershire, England. 2: Dee Estuary, Cheshire, England. 3: Menai Strait, Wales. 4: illustration by A. Hancock (in Eliot, 1910). 5: Orkney.
No large, pale, dorsal mark or significant pale metapodium (‘tail’).
No digitiform tentacles but most have a raised rim around the pale eye patches which Alder & Hancock (1862) in their original species description refer to as ‘lateral crests’. Most subsequent authors omit or deny the existence of the rim/crests on L. depressa (Barrett & Yonge, 1958; Gascoigne, 1975; Thompson,1976; Hayward & Ryland, 1998; Marine Species Identification Portal). Consequently the rim is often mistaken for head crests of L. capitata. The rim varies in how much it is erected, being low when a specimen is not in good condition (2), and it may be difficult to discern in dorsal view of very dark specimens (5).
On tidal saltings in Britain in brackish (1, 2 & 5) or full marine salinity (3). Sublittoral in low salinity of inner Baltic Sea; specimen near Helsinki misidentified (when accessed in June 2021) as L. capitata at www.youtube.com/watch?v=6TBqOdGHmmI .

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