GS3 juveniles in different microhabitats are similar in most respects, except that those in holdfasts have coarser growth lines, and they, and those in depressions on stipes, usually have the rim curved up at the ends (1) so it fits the contour of the inhabited bowl. The apex is lost and the anterior progressively removed, probably by resorption (2) . Growth is greatest at the posterior where the growth lines are most widely spaced (3) . Growth lines form a horseshoe shape, open at the anterior, in plan view. In side view, they slope downwards to where they end in the anterior quarter of the shell (4). The exterior surface is very smooth with no sculpture other than fine growth lines, except those in holdfasts, like on this one, are a little rougher with coarse growth lines. Juveniles rarely, if ever, have any epizoic growths.
Concise
Part 1, SHELL FORMS: 02 Patella pellucida. Growth Stage 2 (GS2). July 2012. Littoral. North Yorkshire, England. © P. Lightfoot.
Part 2, BODY & ANATOMY: 03 Patella pellucida. Growth Stage 3 (GS3). 2009. Sublittoral, Farne Islands, Northumberland, England. © P.Lightfoot.
Part, 3 HABITS & ECOLOGY: 04 Patella pellucida. Length 4.6mm. Growth Stage 3 (GS3). September 2016. Yorkshire, England. © P.Lightfoot.