Evansi Anthias

Evansi Anthias: The Yellowback Reef Dither

The Evansi Anthias (Pseudanthias evansi), often called the Yellowback Anthias or Yellowtail Anthias, is a stunning, active marine fish highly prized for its brilliant coloration. This species typically displays a beautiful cerise-pink to lavender body that contrasts sharply with a striking yellow or gold coloration along its back, dorsal fin, and caudal fin (tail). Males are slightly more vibrant and may develop elongated fin rays.

Native to the Indian Ocean, including the Maldives and Sri Lanka, the Evansi Anthias is a planktivore found schooling in large groups along outer reef slopes and drop-offs where currents deliver a constant supply of food. It is a smaller species, reaching a maximum adult length of around 4 to 5 inches (10-12 cm).

While peaceful and reef-safe, the Evansi Anthias is considered an intermediate to expert-level fish. Its small mouth and high metabolism demand a strict and frequent feeding regimen, making it susceptible to starvation in tanks where it must compete with faster-feeding fish.

Diet & Compatibility:

• Diet: This is a dedicated Planktivore/Carnivore. In the wild, it feeds constantly on zooplankton. In captivity, it requires multiple small feedings (3 to 5 times) per day. The diet must be varied and planktonic in size, including vitamin-enriched frozen foods such as mysis shrimp, cyclop-eeze, capelin roe, and enriched brine shrimp. Newly introduced specimens often require live foods (copepods, enriched artemia) to initiate feeding.
• Feeding: Due to its constant feeding requirement, a well-established tank with an abundant supply of live copepods and amphipods (often cultivated in an attached refugium) is highly beneficial. Skip any day's feeding, and this fish risks decline.
• Reef Compatibility: It is Reef Safe. The Evansi Anthias will not harm corals, clams, or other sessile invertebrates. It is an excellent dither fish, bringing activity to the mid-water column and helping shyer fish feel secure.
• Temperament: It is Peaceful. It should only be housed with similarly docile tankmates. Aggressive or fast-swimming fish will outcompete the Anthias for food and cause it chronic stress, leading to illness. Avoid housing with triggerfish, large aggressive angels, or puffers.
• Social Structure: Like most Pseudanthias species, the Evansi Anthias is a protogynous hermaphrodite, living in harems of one male and several females. They do best kept in a small group of 3 to 7 individuals in a large aquarium (100+ gallons) to allow for a proper social hierarchy. If the dominant male dies, the largest female in the group will typically transition to a male.

Quick Facts

• Scientific Name: Pseudanthias evansi
• Primary Common Name: Evansi Anthias
• Other Common Names: Yellowback Anthias, Yellowtail Anthias
• Origin: Indian Ocean (Maldives, Sri Lanka, Andaman Sea)
• Max Size: 4-5 inches (10-12 cm)
• Temperament: Peaceful / Social (Schooling/Harem)
• Diet: Planktivore (Requires 3-5 small feedings daily)
• Minimum Tank Size: 75 gallons (single), 100+ gallons (harem)
• Reef Compatibility: Yes (Excellent Reef Fish)
• Care Level: Intermediate to Expert