Morphology Data of Fontitrygon margarita
Identification keys
Abnormalities
Main Ref. Compagno, L.J.V. and T.R. Roberts, 1984
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs claspers (m)
Different appearance
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral other
Cross section flattened
Dorsal head profile
Type of eyes more or less normal
Type of mouth/snout
Position of mouth sub-terminal/inferior
Type of scales placoid scales
Diagnosis

Diagnosis: A large Dasyatis species most closely related to the much smaller Dasyatis margaritella and to the extremely flat D. garouaensis (Ref. 26277). Pearl spines always present and very large; denticles on dorsal surface of disc smooth, restricted to middle portion (Ref. 26277).

Description: Disc oval, moderately flat, its medial lobe broad-based and moderately exserted, its anterolateral margin somewhat concave; disc depth 13.0-14.5% of disc width, disc width 0.9-1.1 times disc length (Ref. 26277). Snout moderately long, protruding but not pointed (Ref. 26277, 81259). Eyes rather small, spiracles slightly larger than eyes, nasal curtain posteriorly fringed and a deep groove extends from nasal flap to and around mouth corners (Ref. 81625). Jaws strongly undulate, with 24-32/28-36 tooth rows arranged in a pavement pattern, and five finger-like mouth papillae (Ref. 7397, 81259, 81625). Pelvic fins projecting slightly from posterior disc margin (Ref. 81625). Total number of pectoral radials 129-136 (Ref. 7367, 81625). Middle third of disc covered with small, circular, flat denticles and tail covered with small prickles; no enlarged thorns on disc or tail (Ref. 26277, 81259). Tail long, whip-like behind the sting, broad-based and oval in cross-section, with a dorsal ridge behind the sting and a moderately high ventral fold; tail whip covered with fine dermal denticles (Ref. 81259, 81625).

Colouration: Dorsal side uniformly brownish to greyish-brown, without spots or prominent markings; ventral side pale or whitish with more or less dark pectoral margins (Ref. 26277, 81259, 81625).

Ease of Identification

Meristic characteristics of Fontitrygon margarita

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) present
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal
total 130 - 130

Fins

Dorsal fin(s)

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

Caudal fin

Attributes

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  transformed to 'aerofoils'
Spines     
Soft-rays   
Pelvics Attributes  more or less normal
Position    abdominal
Spines     
Soft-rays   
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Entered by Boden, Gert
Modified by Bailly, Nicolas
Comments & Corrections
Sign our Guest Book
Back to Search
cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17