Saddle Midshipman, Porichthys ephippiatus

Saddle Midshipman, Porichthys ephippiatus. Fish collected from coastal waters off Point Palmilla, Baja California Sur, October 2018. Length: 5.2 cm (2.0 inches). Identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, California.

Saddle Midshipman, Porichthys ephippiatus. Fish collected from coastal waters off Point Palmilla, Baja California Sur, September 2016. Length: 5.4 cm (2.1 inches).

Saddle Midshipman, Porichthys ephippiatus. Fish collected from coastal waters north of Puerto Los Cabos, Baja California Sur, June 2007. Length: 7.8 cm (3.1 inches). Identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, California.

The Saddle Midshipman, Porichthys ephippiatus, is a member of the Toadfish or Batrachoididae Family, and is known in Mexico as sapo enswillado. The species was discovered and introduced as recently as 1988 by Dr. Richard Rosenblatt and my good friend and scientific fish mentor H.J. Walker, Jr. Gobally, there are fourteen species in the genus Porichthys, seven of which are found in Mexican waters, one in the Atlantic and six in the Pacific Ocean.

The Saddle Midshipmen has an elongated body with an oval cross-section. They are brown in color with a golden sheen and have 4 to 6 dark saddles on their back (after which they are named), with occasional spots on their head. Their dorsal fin has up to 22 alternating light and dark blotches along the outer half.  Their anal and caudal fins are white with dark margins. Their pectoral fins are dusky. They have a large head with eyes on top, canine teeth, and a prominent non-venomous spine on their gill cover. Their anal fin has no spines and 26 to 30 rays. They have two stout dorsal spines followed by a separate second dorsal fin with 31 or 32 rays which has a long base. They have 4 conspicuous rows of light organs along their lateral lines. The lower line on their flank has approximately 5 pores behind the end of the light-organ row (a key to identification). They have 7 to 9 lower gill rakers. Their skin is smooth and they do not have scales.

The Saddle Midshipmen is a demersal species that is found over sandy and muddy bottoms at depths between 15 m (50 feet) and 230 m (750 feet). They reach a maximum of 13.5 cm (5.3 inches) in length. They consume crabs, echinoderms, fish, mollusks, and shrimp. The Saddle Midshipman is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Saddle Midshipmen is a resident of Mexican waters of the Pacific Ocean but has a limited range being found only around the southern tip of Baja in Baja California Sur and along the coast of the mainland from Mazatlán, Sinaloa, to Guatemala.

The Saddle Midshipman can be easily confused with the Pearlspot Midshipman, Porichthys margaritatus (white anal fin; predominantly white dorsal fin).

From a conservation perspective the Saddle Midshipmen is currently considered to be of Least Concern with stable, widely distributed populations. They are small in stature, seldom seen by humans, and of limited interest to most.