*Images in development
Cuspidariidae
Radial riblets on part or all of the body of the shell
Body of shell with commarginal sculpture only
Anterior with commarginal ridges abruptly separated from posterior ribbed area
Myonera demistriata
Radial riblets over the whole body, fading anteriorly
Rostrum long, body oval, median area with riblets
With 20 primary radial riblets without or with few secondary riblets
Rostrum very short, truncate
Rostrum short to very long, roundly pointed
Rostrum smooth with 2 weak radial keels
We have only examined the single valve collected by the Porcupine Expedition. It shows no sign of cardinal teeth so does not conform with the definition of Pseudoneaera given by Poutiers & Bernard (1995).
Pseudoneara truncata
Weak anterior tooth in each valve.
Poutiers & Bernard (1995) recognise with reservations the following species recorded from the NE Atlantic, P. atlantica, P. colpodes, P. ruginosa and P. verityi. We are unable to make definitive identifications within this group of species.
Protocuspidaria spp.
[Taxon under review]
Posterior set off by a sharp angulate ridge, rostrum broad, rounded and lacking radial sculpture
Tropidomya abbreviata
Posterior not set off by a sharp angulate ridge
With accessory shelf supporting the posterior adductor in both valves, This is not part of the hinge and should not be confused with posterior lateral teeth
Hinge with or without lateral teeth, posterior adductor scar with no supporting shelf.
Body deep (H=L), rostrum very short, sulcus weak, sculpture on body of well defined commarginal very fine ridges.
Halonympha inflata
Body of shell ovate (L>H). rostrum short defined by change in sculpture, rostrum wrinkled, body with commarginal lines but appears smooth.
Halonympha depressa
Posterior roundly pointed, rostrum very short not defined ventrally, anterior of body with widely spaced commarginal ridges, hinge with a single posterior lateral in the RV
Cuspidaria undata
Body with lamellar commarginal sculpture
Body with commarginal sculpture of incremental lines and growth stops only
Rostrum long, making posterior of shell longer than anterior, hinge lacking teeth
Myonera alleni
Hinge with at least a single posterior lateral in the RV
Rostrum set off by a weak rounded ridge and with 2-3 faint radial ridges along the rostrum.
Myonera sulcifera is said to have a weak posterior cardinal in the RV but we cannot discern this in the Porcupine shells
Myonera sulcifera
Rostrum defined by a shallow sulcus only, overall minutely granular more prominent on rostrum
Myonera sp.
Hinge with only a posterior lateral in RV
Rostrum not as long as body
With commarginal lines and growth stops only
Rostrum not twisted to one side
Dorsal margin of rostrum sloping gently some slightly up-curved, anterior dorsal margin high (bathyal)
Cuspidaria obesa
