Pacific Snake Eel, Ophichthus triserialis
The Pacific Snake Eel, Ophichthus triserialis, whose common Spanish name is tieso del Pacifico, is a species in the Snake Eel or Ophichthidae Family, known collectively as tiesos in Mexico. Globally, there are sixty-six species in the genus Ophichthus, nine of which are found in Mexican waters, three in the Atlantic and six in the Pacific.
The Pacific Snake Eels have robust cylindrical bodies. They have a tan coloration and a rounded cross section with two rows of large dark brown spots on their body, one along their dorsal fin and the other along their lateral line. Their dorsal fin is yellow with a series of dark oblong spots along its outer half. There are also smaller spots scattered along their belly and on their sides and top of their head. Their anal and pectoral fins are dusky. Their head has an overhanging snout with a large mouth and large eyes located above the middle of the mouth. Their rear nostril is located before the eyes and is covered with a long fleshy flap that extends below the top lip. They have pointed teeth with two rows on each jaw and one row on the roof of their mouth; they do not have canine teeth. Their dorsal fin originates over the rear of their well-developed pectoral fin. Their tail, which is blunt and ends in a hard finless point, is 53 to 58% of total length. They have no scales.
The Pacific Snake Eels are mostly found within burrows in sandy and muddy bottoms at depths up to 500 feet. They reach a maximum length of 1.13 meters (3 feet 8 inches). They are a poorly studied species and very little is known about their behavioral patterns.
In Mexican waters the Pacific Snake Eels are found in all waters of the Pacific.
The Pacific Snake Eel can be confused with the Longfin Spotted Snake Eel, Myrichthys aspetocheiros (throat and dorsal fin without spots), the Mustachioed Snake Eel, Herpetoichthys fossatus (tail less than one-half total length; minute pectoral fins), and the Tiger Snake Eel, Myrichthys tigrinus (pale dorsal fin margin; broad pectoral fin base; spots of uniform size).
The Pacific Snake Eels, although fairly abundant and of good size, are of limited interest to most and normally a “catch and release.”