Manta birostris and alfredi

MANTA RAYS  

SCIENTIFIC CLASSIFICATION

CHONDRICHTHYES: Manta rays are related to sharks. Sharks and rays are cartilaginous fishes as opposed to bony fishes. Cartilaginous fishes are known as Chondrichthyes.

 

ELASMOBRANCHS: Rays and sharks are called Elasmobranchs. Loosely translated, elasmos means plate-like or beaten metal and branchia means gills in Latin. Unlike many shark species, manta rays do not have sharp teeth. They possess a sand-paper like tooth band along the lower jaw only.

 

MOBULIDAE: Manta rays belong to the family of rays referred to as devil rays, scientifically called Mobulidae. Devil rays share the common characteristic of cephalic or head fins. When unfurled, the fins help to funnel in food and water into the mouth. To make the fins more streamlined, devil rays can roll up these flexible appendages. When furled, these fins were thought to resemble a devil’s horns.

 

SPECIES: According to Marshall (2009), manta rays are divided into two different species: Manta birostris and Manta alfredi. Manta birostris are more oceanic and migratory. They are regularly sighted at offshore islands, oceanic seamounts, and submarine ridge systems. Manta birostris are located in the Atlantic, Indian and Pacific oceans. This species can reach up to 22’ across. Manta alfredi is a smaller species that has an average size of 11’ across. This species is commonly sighted near shore around coral or rocky reefs, often times in residential groups. The species is widespread in tropical waters and found in the Atlantic, Indian, and Pacific oceans. Manta birostris is occasionally sighted along the Kona Coast usually off the points. Manta alfredi is the species of manta ray sighted on the Kona Manta Ray Night Dive.

 

COLOR AND MARKINGS: Most often manta rays are black dorsally with white “shoulder bars”. While the dorsal coloration is relatively similar in mantas worldwide, their ventral side can be very different. Typically, Manta birostris has few spots ventrally with wide gray bands along the back edge of the wings. Manta alfredi has big blotchy spot patterns ventrally located. These spot patterns are unique to each manta and can be used for accurate identification. The most extreme difference in manta coloration comes with the “black manta”. These mantas are predominantly black on their ventral surface with small spots or patches of white. Both Manta birostris and Manta alfredi species have a black coloration. Both black and white mantas can be seen together in some locations.