Main Ref. | Sabelli, B. and H.S. Feinberg (eds.), 1879 |
Appearance refers to |
specialized organs | |
different appearance | |
different colors | |
remarks |
Striking features | |
Body shape lateral | |
Cross section | |
Dorsal head profile | |
Type of eyes | |
Type of mouth/snout | |
Position of mouth | |
Diagnosis | Shell: moderately swollen, thick and robust valves, almost circular, equivalved and inequilateral; has a thick dark brown to blackish periostracum; sculpture consists of thin concentric grooves; well-developed external ligament, reaching the end of the posterior margin of the valve, posterior to the umbones; hinge is heterodont, right and left valves each has three cardinal teeth, anterior and posterior lateral teeth; inside the valves are two slightly different muscle scars (dimyarian, anisomyarian), linked by a continuous pallial line (integropalliate), without a sinus; crossed-lamellae structure. Body: pair of gills each consists of two series of lamellae extensively linked by interlamellar junctions (eulamellibranch); foot is large and the two mantle lobes fuse to form two stout siphons. |
Ease of Identification |
Lateral Lines | Interrupted: No |
Scales on lateral line | |
Pored lateral line scales | |
Scales in lateral series | |
Scale rows above lateral line | |
Scale rows below lateral line | |
Scales around caudal peduncle | |
Barbels | |
Gill clefts (sharks/rays only) | |
Gill rakers | |
on lower limb | |
on upper limb | |
total | |
Vertebrae | |
preanal | |
total |
Attributes | |
Fins number | |
Finlets No. | Dorsal |
Ventral | |
Spines total | |
Soft-rays total | |
Adipose fin |
Attributes |
Fins number | |
Spines total | |
Soft-rays total |
Pectoral | Attributes |
spines | |
soft-rays | |
Pelvics | Attributes |
Position | |
spines | |
soft-rays |