Pandora pinna, (MONTAGU, 1803)

Machado, Fabrizio Marcondes, Passos, Flávio Dias & Giribet, Gonzalo, 2019, The use of micro-computed tomography as a minimally invasive tool for anatomical study of bivalves (Mollusca: Bivalvia), Zoological Journal of the Linnean Society 186, pp. 46-75 : 50

PANDORA PINNA (MONTAGU, 1803)

( FIGS 2, 3)

Description

Shell: Subquadrate to subovate,robust,very compressed, strongly inaequivalve with left valve inflated and right valve flat or slightly concave; lithodesma absent.

Mantle: Mantle margin fused forming a short anterior pedal aperture and posteriorly with two short and very similar siphons; fourth pallial aperture absent.

Siphons: Inhalant and exhalant siphons similar in size and outline, simple tube-shaped, fused almost until the tip but not covered with periostracum; apertures of the inhalant and exhalant siphons fringed with a ring of, respectively, ~18 and ~16 short tentacles.

Ctenidia: Eulamellibranch and plicate; complete with a large inner demibranch and a much reduced outer demibranch consisting only of reflected descending lamellae; presence of a marginal food groove on the inner demibranch.

Labial palps: Large, wide, lamellate with sorting ridges, complete and symmetrical (typically bivalve plan).

M u s c u l a t u r e: A d d u c t o r m u s cl e s p r e s e n t, w e l l developed, posterior slightly larger than anterior; presence of poorly developed posterior and anterior pedal retractor muscles.