Main Ref.	Wells, F.E., 1985
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 high, with 10 to whorls, flat sided. Two channels and an impressed suture can be found on the upper whorls, and about 10 channels on the body whorl are crossed by axial ribs, producing squarish beads. Beads on each whorl are all of similar size. Outer lip is flared in aduls, and thickened with both anterior and posterior canals. Columella is smooth, and thickened along full height. Shell is dark brown. Aperture is whitish. Operculum is light brown and horny.
Ease of Identification

Meristic characteristics of Pirenella alata

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