Main Ref.	Sabelli, B. and H.S. Feinberg (eds.), 1879
Appearance refers to

Sex attributes

specialized organs
different appearance
different colors
remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Diagnosis	Shell: delicate, moderately swollen, equivalve and inequilateral, yellowish-whitish in color; sculpture has thin pink concentric lamellae, well-spaced, curve, grooved on the outer surface, prolonged posteriorly to form a spoutlike process; in between lamellae are thin growth lines; very longe ligament deeply set in the dorsal margin runs from the umbones to the end of the hinge which is heterodont with only three cardinal teeth on each valve; muscle scars almost equal (dimyarian, isomyarian); Pallial line has a shallow sinus (sinopalliate). Body: pair of gills each has two series of lamellae extensively fused in interlamellar junctions (eulamellabranch); foot and siphon moderately developed.
Ease of Identification

Meristic characteristics of Circomphalus disjectus

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

Fins

Dorsal fin(s)

Attributes
Fins number
Finlets No.	Dorsal
	Ventral
Spines total
Soft-rays total
Adipose fin

Caudal fin

Attributes

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral	Attributes
	spines
	soft-rays
Pelvics	Attributes
	Position
	spines
	soft-rays