Morphology Data of Chrysichthys nyongensis
Identification keys
Abnormalities
Main Ref. Geerinckx, T., L. Risch, E.J. Vreven, D. Adriaens and G.G. Teugels, 2007
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
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales
Diagnosis

Diagnosis: width (as percentage of length) of occipital process) 67-93% (average 79%); depth (as percentage of width) of premaxillary tooth plate 29-43% (average 35%); vomerine dentition generally present as isolated teeth, exceptionally forming small tooth plates, palatine teeth mostly absent, but sometimes present (in mature males)(Ref. 81642).

Description: snout pointed; mouth rather small, with a premaxillary toothband width 12.5-20% (generally 16.6%) HL; occipital process broad (base length 6-8 times in HL); vomerine dentition present as small toothbands (in 47% of specimens), as a few isolated teeth (in 35% of specimens) or absent (in 18% of specimens); few individuals have 1-2 palatine teeth, but great majority lack a palatine dentition; dorsal fin of medium height (29-37% SL); anal fin with 4-5 soft unbranched rays and 7-9 branched rays; (only three) males (160-186 mm SL) with enlarged testes and a single gravid female (172 mm SL) are known; mature males do not exhibit inflated heads and widened mouths of Chrysichthys and Melanodactylus species, however their vomerine dentition is more pronounced and present as a small tooth plate, and all have teeth on palatine (Ref. 81642).

Coloration: preserved specimens with head and dorsum dark brown, creamy white ventrally (Ref. 81642).

Ease of Identification

Meristic characteristics of Chrysichthys nyongensis

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 14 - 15
on upper limb
total
Vertebrae
preanal
total

Fins

Dorsal fin(s)

Attributes
Fins number 1
Finlets No. Dorsal   0
Ventral  0
Spines total 2 - 2
Soft-rays total 6
Adipose fin present

Caudal fin

Attributes

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  
Spines     1
Soft-rays   9
Pelvics Attributes  
Position    
Spines     
Soft-rays   
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Comments & Corrections
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