Morphology Data of Petromyzon marinus
Identification keys
Abnormalities
Main Ref. Maitland, P.S. and R.N. Campbell, 1992
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features striking type of mouth
Body shape lateral eel-like
Cross section circular
Dorsal head profile clearly convex
Type of eyes more or less normal
Type of mouth/snout sucker-like
Position of mouth sub-terminal/inferior
Type of scales scales embedded or partly/completely absent
Diagnosis

Anguilliform body (Ref. 51442). Jawless with a round sucker-like mouth and sharp teeth arranged in many consecutive circular rows (Ref. 88171). Presence of 7 branchial openings behind the eye (Ref. 51442, 88171). Lacks paired fins (Ref. 88171). Number of myomeres: 67-74 (Ref. 6258, 89241). Olive or brown-yellow on the dorsal and lateral part of the body, with black marblings; becomes lighter ventrally (Ref. 35388, 51442, 58137). Back, side and fins with prominent black mottling; oral disc as wide or wider than head (Ref. 86798). Adults: 11.4-120.0 cm TL. Body wet weight of the 120 cm TL individual was 2.3 kg. Maximum size attained by landlocked populations in the Laurentian Great Lakes, 60 cm TL. Body proportions, as percentage of TL (based on a variable number of specimens and sizes as indicated after the ranges): prebranchial length, 9.2-16.0 (in 46 specimens 19.2-82.75 cm TL); branchial length, 8.1-16.0 (in 46 specimens 19.2-82.75 cm TL); trunk length, 45.6-58.5 (in 42 specimens 25.6-82.75 cm TL); tail length, 22.0-42.2 (in 46 specimens 19.2-82.75 cm TL); eye length, 0.8-3.6 (in 49 specimens 13.5-82.75 cm TL); disc length, 4.5-9.3 (in 58 specimens 13.5-83.5 cm TL); snout length, 6.5-10.9 (in 41 specimens 25.6-82.75 cm TL). Urogenital papilla length, as a percentage of branchial length, in seven spawning males measuring 38.5-49.2 cm TL, 9.5-13.0. Spawning males develop a rope-like dorsal ridge ahead of the first dorsal fin and extending to the level of the posterior part of the branchial region, and hence, are sometimes called corded males. Dentition: supraoral lamina, 1 bicuspid tooth; infraoral lamina, 6-10 unicuspid teeth, the lateralmost sometimes bicuspid; 4 endolaterals on each side; endolateral formula, typically 2-2-2-2; 3 rows of anterials; first row of anterials, 1 unicuspid tooth; 5-7 rows of exolaterals on each side; 3 rows of posterials; first row of posterials, 10 unicuspid teeth; transverse lingual lamina strongly w-shaped, with 12-14 cusps, the median one not enlarged; longitudinal lingual laminae j-shaped, each with 12-14 cusps. Moderately well-developed marginal membrane. Velar tentacles, 2-3, smooth. Body coloration (preserved), newly-transformed individuals 13.5-17.5 cm TL have their colour grading from gray-bluish dorsally to silvery white ventrally while in individuals 45 cm TL or more the dorsal and lateral aspects become mottled and the ventral aspect remains uniformly pale. The iris is golden yellow. Lateral line neuromasts unpigmented or darkly pigmented. Extent of caudal fin pigmentation, 75% or more. Caudal fin shape, spade-like. Oral fimbriae, 114-150. Oral papillae, 24-33 (Ref. 89241).

Ease of Identification likely to be confused with closely related species.

Meristic characteristics of Petromyzon marinus

Lateral Lines Interrupted: No
Scales on lateral line 0 - 0
Pored lateral line scales 0 - 0
Scales in lateral series 0 - 0
Scale rows above lateral line 0 - 0
Scale rows below lateral line 0 - 0
Scales around caudal peduncle 0 - 0
Barbels
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal 0 - 0
total 0 - 0

Fins

Dorsal fin(s)

Attributes
Fins number 2
Finlets No. Dorsal   
Ventral  
Spines total
Soft-rays total
Adipose fin absent

Caudal fin

Attributes more or less truncate; confluent

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  absent
Spines     0
Soft-rays   0 - 0
Pelvics Attributes  suppressed/absent
Position    absent
Spines     0
Soft-rays   0 - 0
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Comments & Corrections
Back to Search
cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17