Morphology Data of Malapterurus occidentalis
Identification keys
Abnormalities
Main Ref. Norris, S.M., 2002
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral fusiform / normal
Cross section circular
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales
Diagnosis

Diagnosis: tooth patches narrow; vertically based pectoral fin positioned near body mid-depth; 7-8 branched caudal-fin rays; eye relatively large; interorbital space relatively narrow; 8-9 pectoral-fin rays; 36-38 vertebrae; young tan or brown; caudal saddle and bar pattern present in juveniles but poorly developed in adults; flank and dorsum marked with small spots but no large blotches; caudal fin not heavily marked with spots or blotches (Ref. 44050).

Description: body and head cylindrical; 15-17 abdominal vertebrae; 21 caudal vertebrae; 19 caudal-fin rays (arrangement: ii-7-8-ii) (Ref. 44050, 57130).

Coloration: head and body bicolored in shades of tan or grey; flank and dorsum marked with scattered small spots, which generally do not continue onto rayed fins; adipose fin pigmented as the dorsum; pectoral and pelvic fins may be dusky in adults; anal fin usually darkly pigmented with a pale distal margin; caudal fin with pale basal crescent in younger specimens; large adults may show a hint of a caudal bar and pale interspace; juveniles show the caudal saddle and bar pattern: caudal bar dark, saddle well defined but faint; caudal fin darkly pigmented (little darker than flank base color) with pale distal margin and broad pale basal crescent (Ref. 44050).

Ease of Identification

Meristic characteristics of Malapterurus occidentalis

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 12 - 19
on upper limb 2 - 3
total 14 - 22
Vertebrae
preanal
total 36 - 38

Fins

Dorsal fin(s)

Attributes greatly reduced or absent
Fins number
Finlets No. Dorsal   0
Ventral  0
Spines total 0
Soft-rays total 0
Adipose fin present

Caudal fin

Attributes more or less normal

Anal fin(s)

Fins number 1
Spines total 0
Soft-rays total 9 - 11

Paired fins

Pectoral Attributes  more or less normal
Spines     0
Soft-rays   8 - 9
Pelvics Attributes  more or less normal
Position    abdominal
Spines     0
Soft-rays   6 - 7
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