Sea Horse Structure and Size

 
 

External Structure      Sea Horses have segmented bodies and tails encased in numerous joined bony rings.  They have lobate gills and a tubular snout with a small toothless mouth at the end.  They lack spinuous caudal and ventral fins (Bohlke and Chaplin 1968); however, they do have dorsal fins for forward movement  and pectoral fins for steering (Vincent 1999).  Like most other fish, the head and body of sea horses are in the same plane (Bohlke and Chaplin 1968).  Males differ from females in that males have a front brood pouch for carrying their unborn offspring (Hunter 1931).  On the head of the sea horse is a coronet that makes each sea horse unique, as a thumb print does for a human.  Also sea horses can camouflage themselves.  Since they are so slow moving, this helps them to escape from predators more easily (Vincent 1997).  The rigid bodies of sea horses also hinders their swimming speed.  They have a tough, transparent enamel-like skin covering the distinct plates that cover their bodies.  This makes then a primitive ganoid (Crowder 1928).

Size      The size of sea horses varies greatly between species.  Then smallest can be 1/4 of an inch while the largest are more than a foot in length (Vincent 1997).  Matlock's (1992) research off the Texas coast indicated a linear relationship in sea horse length in comparison to age for the lined sea horse, Hippocampus erectus.  The relationship he found was that:  Total Length = 21.4 + 0.107 A, where A is age in days of the sea horse.

 

If you have any questions, please contact Leslie Cook.