Shovelnose Guitarfish, Pseudobatos productus
Shovelnose Guitarfish, Pseudobatos productus. Fish caught from coastal waters within the Devil’s Curve section of Magdalena Bay, Baja California Sur, May 2019. Length: 76 cm (2 feet 6 inches). Photograph courtesy of Dr. Larry Overman, Newport Beach, California.
Shovelnose Guitarfish, Pseudobatos productus. Fish caught from coastal waters off Santa Catalina Island, California, September 2016. Length: 76 cm (2 feet 6 inches). Catch, photograph and identification courtesy of Chris Wheaton, Fullerton, California.
Shovelnose Guitarfish, Pseudobatos productus. Fish caught from coastal waters within the Devil’s Curve section of Magdalena Bay, Baja California Sur, January 2017. Length: 76 cm (2 feet 6 inches). Catch and photograph courtesy of Brad Murakami, Surrey, British Columbia, Canada.
Shovelnose Guitarfish, Pseudobatos productus. Fish caught in coastal waters off Bahía Santa Rosalillita, Baja California, August 2017. Catch and photograph courtesy of Barry Mastro, Escondido, California.
Shovelnose Guitarfish, Pseudobatos productus. Fish caught from coastal waters off San Diego, California, September 2011. Length: 1.09 m (3 feet 7 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
The Shovelnose Guitarfish, Pseudobatos productus, is a member of the Guitarfish or Rhionobatidae Family, and is known in Mexico as guitarra viola. There are eight global members of the genus Pseudobatos, two of which are found in Mexican waters of the Atlantic and five in Mexican waters of the Pacific Ocean.
The Shovelnose Guitarfish has a shark-like body and a large triangular head that tapers to a pointed blunt snout and incorporate the fused pectoral fins. Their discs are longer than they are wide. They are yellowish-brown in color with a slightly translucent snout. Their ventral side is off-white. In some fish, the snout tip is black. Most live fish have a series of paired and irregular dark blotches on their cheeks, on the rear of their head, along their upper flanks, and on their pectoral fins. Their head is relatively slender and their snout has 2 narrow cartilaginous ridges that are close together for the first half of their length. They have a large spiracle behind each eye (pictured below), with 2 skin folds, the outer fold being larger that the inner fold. Their body is covered with small denticles. They have 1 row of thorns along the mid-line of their back starting from behind their eyes to the origin of their first dorsal fin. They also have 2 spines on each shoulder and several around each eye and above each spiracle. Their caudal fin is asymmetrical and without a distinct lower lobe. They have 2 large triangular-shaped dorsal fins of equal size.
The Shovelnose Guitarfish is a demersal species that form large schools in shallow coastal waters over sandy and muddy bottoms in bays and estuaries at depths up to 91 m (300 feet). They reach a maximum of 1.56 m (5 feet 1 inch) in length and 18.4 kg (47 lbs) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 13.04 kg (28 lbs 12 oz) with the fish caught from coastal waters off Ensenada, Baja California, April 2021. They consume a wide variety of crustaceans and small fish. They are masters at camouflage and have the ability to rapidly change colors to match their substrate. Reproduction is via yolk sac with offspring born alive in litters of 1 to 16. The Shovenose Guitarfish 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 Shovelnose Guitarfish a resident of all Mexican waters of the Pacific Ocean with the exception that they are absent from of along the coast of the mainland south of Acapulco, Guerrero to Guatemala.
The Shovelnose Guitarfish is most likely confused with the Speckled Guitarfish, Pseudobatos glaucostigma (snout with 2 wide cartilaginous ridges; pectoral and pelvic fins with pale margins), the Spiny Guitarfish, Pseudobatos spinosus (body covered with spines), and the Whitesnout Guitarfish, Pseudobatos leucorhynchus (white or transparent snout).
From a conservation perspective the Shovelnose Guitarfish and currently considered to be Near Threatened with declines in their overall populations of 30% over the past 3 generations. They are heavily targeted by artisanal fishermen in all Mexican waters of the Pacific and also retained by bottom trawlers and gill net fishermen. They are also a favorite of recreational fishermen in California. Regulations have been implemented in the United States and in Mexico but have had limited impact as their populations continue to decline. They have been utilized as food by Native Americans for centuries although currently their food value is considered of very marginal. A small percentage of the catch is made into fish meal. They are considered harmless to humans.