Morphology Data of Hymenocephalus aterrimus
Identification keys
Abnormalities
Main Ref. Schwarzhans, W., 2014
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 elongated
Cross section angular
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales
Diagnosis

This species is distinguished by the following characters: a black-colored large-headed fish, with head size 21-25% TL; pelvic fin rays 13-14; pectoral fin rays 13-16; projecting snout, 20-24% HL; head bones are papery thin and often distorted; no barbel; small orbit diameter, 20-24% HL; interorbital width 60-70% HW; infraorbital width 20-25% HL; postorbital-preopercular interspace 10-14% HL; preopercular supporter is very small and forked; gill rakers 21-25; ventral striae reaching to about ? from pelvic fin bases to periproct; small otolith with rounded outline, no predorsal lobe developed; colliculi separated; otholith length to height (OL:OH), 1.0-1.2; total colliculum length to pseudocolliculum length (TCL:PCL) is 2.2-2.8 (Ref. 98298).

Ease of Identification

Meristic characteristics of Hymenocephalus aterrimus

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 21 - 25
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  more or less normal
Spines     
Soft-rays   13 - 16
Pelvics Attributes  more or less normal
Position    
Spines     
Soft-rays   13 - 14
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
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