Pacific Stargazer, Astroscopus zephyreus

Pacific Stargazer, Astroscopus zephyreus. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, February 2008. Length 56 cm (22 inches).

Pacific Stargazer, Astroscopus zephyreus. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, March 2012. Length: 41 cm (16 inches).

Pacific Stargazer, Astroscopus zephyreus. Underwater photographs taken in Zihuantanejo Bay, Guerrero, February 2023. Photographs courtesy of Ron Woheau, Zihuantanejo.

The Pacific Stargazer, Astroscopus zephyreus, is a member of the Stargazer or Uranoscopidae Family, and known n Mexico as miracielo perro. Globally, there are four species in the genus Astroscopus, of which two are found in Mexican waters, one in the Atlantic and one, this species, in the Pacific Ocean.

The Pacific Stargazer has a robust body that tapers from the mid-body to the tail. They are grayish-brown dorsally and transition to white ventrally. Their head and body are covered with numerous small white spots. Their anal, pectoral, and pelvic fins are white. Their caudal and dorsal fins are dark. Their head is flattened and disproportionately large. They have small eyes that point skyward and a large vertical mouth. They have a pair of electric organs located directly behind their eyes and a blunt spine on the corner of their gill covers. Their anal fin lacks spines; their first dorsal fin has 4 spines and 1 ray; their second dorsal fin has 12 rays and is set close to the first; and, their pectoral fins are simply ginormous. They are covered with small scales and their lateral line is continuous.

The Pacific Stargazer is a solitary benthic coastal species normally found submerged in substrate (beaches, sand bottoms, and soft bottom habitats in mangroves and estuaries) at depths between 8 m (25 feet) and 385 m (1,265 feet). They reach a maximum of 56 cm (22 inches) in length, which was established by the fish photographed above. They are ambush predators that lie in wait with only their eyes exposed; they consume small invertebrates and small fish. The Pacific Stargazer 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 Pacific Stargazer is a resident of all Mexican waters of the Pacific Ocean.

The Pacific Stargazer can be confused with the Smooth Stargazer, Kathetostoma averruncus (large eyes; first dorsal fin does not have spines; large white spots on body, caudal, and dorsal fins).

From a conservation perspective the Pacific Stargazer has not been formally evaluated. They are prone to habitat loss, including mangroves, from coastal development. They are a large fish but seldom seen by humans and of limited interest to most. They are consumed by locals on a limited basis and are reported to make good sushi but due to the venom present in this fish I do not recommend human consumption. A word of caution! The Pacific Stargazers have a pair of large poisonous spines, with a venom gland located immediately above their pectoral fins and behind their gill covers. Venom from these fish has been reported to cause death in humans, therefore handling of this species should be avoided. They are also capable of delivering electrical shocks of up to 50 volts.