Morphology Data of Istiophorus platypterus
Identification keys
Abnormalities
Main Ref. Nakamura, I., 1985
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs no special organs
Different appearance males alike females
Different colors
Remarks

Descriptive characteristics of juvenile and adult

Striking features striking type of mouth
Body shape lateral elongated
Cross section compressed
Dorsal head profile clearly concave
Type of eyes more or less normal
Type of mouth/snout more or less normal
Position of mouth sub-terminal/inferior
Type of scales
Diagnosis

This species is distinguished by the following characters: slender elongate and fairly compressed with a high, sail-like first dorsal fin; upper jaw prolonged into a very long beak, slender and round in cross-section; jaws and palatines with villiform teeth; no gill rakers; two dorsal fins, the first very large (42-49 rays) the second small (6-7 rays); pectoral fins 18-20 rays; pelvic fins I, 2 soft rays fused together, very long and narrow, depressible into a groove; caudal peduncle with double keels on each side; body covered with small, embedded scales with 1 or 2 blunt points. Colour of back dark with about 20 bluish vertical bars; belly pale silver; membrane of first dorsal fin blue- black with numerous dark spots; bases of first and second anal fins often tinged with silvery white; remaining fins blackish brown or dark blue (Ref. 43, 26938).

Ease of Identification

Meristic characteristics of Istiophorus platypterus

Lateral Lines 1 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 0
Gill clefts (sharks/rays only) absent
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal
total

Fins

Dorsal fin(s)

Attributes extending over most of the back length
Fins number 2
Finlets No. Dorsal   0 - 0
Ventral  0 - 0
Spines total 0 - 0
Soft-rays total 47 - 53
Adipose fin absent

Caudal fin

Attributes forked; more or less normal

Anal fin(s)

Fins number 2
Spines total 2 - 2
Soft-rays total 12 - 15

Paired fins

Pectoral Attributes  more or less normal
Spines     0
Soft-rays   18 - 20
Pelvics Attributes  largely reduced to one ray
Position    thoracic  beneath origin of D1
Spines     0
Soft-rays   1
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Entered by Luna, Susan M.
Modified by Capuli, Estelita Emily
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cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17