Watanabei Angelfish Male

Genicanthus watanabei, also known as the blackedged angelfish or Watanabe’s angelfish, is a captivating marine ray-finned fish belonging to the family Pomacanthidae. This exquisite species is found in the Pacific Ocean and exhibits fascinating characteristics.

• Description:
  • Sexual Dichromatism: Like other angelfishes in the genus Genicanthus, males and females of G. watanabei display differences in color and pattern.
    • Males: Pale blue to bluish-grey on the upper third of their bodies, with the lower two-thirds adorned by eight horizontal, thin black stripes. The highest of these stripes culminates in a patch of yellow color.
    • Females: Overall light blue with wide black bars across their head and a black spot on the snout.
  • Both sexes exhibit a wide submarginal band on the dorsal and anal fins, as well as on the lobes of the caudal fin. Juveniles somewhat resemble females in color.
  • The forked tail narrows at its base, creating a distinctive “swallow tail.”

• Distribution:
  • G. watanabei is found across a wide range in the Pacific Ocean:
    • From Taiwan east to the Cook Islands and Tuamotu Archipelago.
    • North to the Ryukyu Islands.
    • South to New Caledonia and the Austral Islands.
    • It even occurs on the Great Barrier Reef, with juveniles reaching as far south as Sydney.

• Habitat and Biology:
  • Depth Range: 12 to 81 meters (39 to 266 feet).
  • Preferred Locations: Outward slopes of reefs and drop-offs with strong currents.
  • Diet: G. watanabei feeds on plankton in the water column.
  • Reproductive Strategy: Protogynous hermaphrodite (starting as female, dominant female may change into a male).
    • Lek Mating System: Large males control territories, and females move freely between these territories. Males display to receptive females by swimming on their sides and vibrating their fins. Dominant males prefer to breed with younger females.

• Systematics:
  • First formally described in 1970 by Japanese ichthyologists Fujio Yasuda and Yoshiaki Tominaga.
  • The specific name honors the Japanese ichthyologist Masao Watanabe of Waseda University, who originally collected this fish but initially identified it as Genicanthus caudovittatus.

Genicanthus watanabei is a sought-after reef aquarium species, known for its striking appearance.