[Ebook] Encyclopedia of Aquarium & Pond Fish – Directory of Marine Fish – Squirrelfish

Directory of Marine Fish

Squirrelfish

The red color, large eyes, and fitful movements of these attractive fish are reminiscent of terrestrial squirrels. The eye size is an adaptation for nocturnal living in sheltered areas near the base of coral reefs, where it is vital to gather as much light as possible from the gloomy surroundings. Certain species are known as soldierfish, and this name is often used interchangeably with squirrelfish, but in zoological terms, only the subfamily Myripristinae can be correctly described as soldierfish.

Bigeye Soldierfish (Myripristis bernelti)

• ORIGINS: Found on reefs over a wide area from East Africa across the Pacific to Tahiti and Hawaii.
• SIZE: 10 in (25 cm).
• DIET: Animal-based foods.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Social with its own kind.

The large eyes and the mottled appearance caused by the dark-edged scales are the most distinctive features of this species. It will adapt to daylight feeding. Soldierfish are fairly easy to keep, but they should be housed in groups; otherwise, they remain nervous in aquarium surroundings. This means that a relatively large tank is required.

Whitetip Soldierfish (Myripristis vittata)

• ORIGINS: Indo-Pacific; range includes the Maldives, Australia’s Great Barrier Reef, and Samoa.
• SIZE: 15 cm (6 in).
• DIET: Fresh or thawed invertebrates, such as mussels.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Social with its own kind.

The white tips on the front dorsal fin help to identify the Whitetip Soldierfish. Like other soldierfish, it can vocalize, making a grunting sound by contracting the muscles surrounding its swim bladder and grinding its pharyngeal teeth (located at the back of the throat). Grunting is most likely to be heard if the fish feels threatened. This species usually swims in the lower part of the aquarium, although, like other soldierfish, it prefers to feed in the upper levels, rather than from the substrate.

Tailspot Squirrelfish (Sargocentron caudimaculatum)

• ORIGINS: Ranges from East Africa, through the IndoPacific, to the Maldives, Vanuatu, and Samoa.
• SIZE: Up to 10 in (25 cm).
• DIET: Fresh or prepared meat-based foods.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Shy, but social with its own kind.

The large scales that characterize this group of fish are clearly visible in the Tailspot Squirrelfish, where they are emphasized by their silvery outlines. These squirrelfish are shy by nature, so the aquarium needs to incorporate the equivalent of rocky ledges, where the fish can hide away. In addition, the lighting must not be too bright, or it may deter the fish from feeding.

Violet Squirrelfish (Sargocentron violaceum)

• ORIGINS: Reefs throughout the Indo-Pacific region, including the Maldives, Vanuatu, and Samoa.
• SIZE: 9 in (23 cm).
• DIET: Likes crustaceans, such as shrimp.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Not suitable for a reef aquarium.

Squirrelfish generally have a divided dorsal fin, with the taller part located close to the caudal fin. In this species, the fins as well as the body are suffused with violet. Found at greater depths than many other reef fish, Violet Squirrelfish will tolerate lower water temperatures. They will not thrive if the water in the aquarium is too warm, and often become reluctant to feed.

Crown Squirrelfish (Sargocentron diadema)

• ORIGINS: Ranges widely from the Red Sea to the Hawaiian islands.
• SIZE: 8 in (20 cm).
• DIET: Shellfish and fish.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Not suitable for mixing with smaller fish

The white stripes running along the sides of the body help to distinguish the Crown Squirrelfish from related species. The stripes extend across the gill covers and around the mouth. These are lively, active fish and, like other members of the group, are best kept as a small shoal in a single-species setup. Relatively subdued lighting above the aquarium is recommended. A blue fluorescent night-light will allow you to watch the fish as they become active after dark.

Blackfin Squirrelfish (Neoniphon opercularis)

• ORIGINS: Found throughout the Indo-Pacific region, including the Maldives and Samoa.
• SIZE: Up to 14 in (36 cm).
• DIET: Fresh and thawed invertebrates.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Highly social with its own kind.

Like other squirrelfish, the Blackfin lives in shoals. Although a group of squirrelfish in a tank is likely to contain both males and females, it has not yet been possible to breed squirrelfish in home aquariums.They probably need the stimulus of large numbers of their own kind to trigger spawning. Space is likely to be restricted in the tank, so there will almost certainly be too few fish in the shoal. Only when the females swell with eggs is any difference evident between the sexes.

Longspine Squirrelfish (Holocentrus rufus)

• ORIGINS: Tropical western Atlantic, including the vicinity of the Bahamas.
• SIZE: 6 in (15 cm).
• DIET: Meat-based foods.
• WATER: Temperature 72–79°F (22–26°C); alkaline (pH 8.0–8.3) with SG 1.022–1.025.
• TEMPERAMENT: Kills invertebrates and small companions.

A distinctive feature of this species is the long rear part of the dorsal fin. All squirrelfish are well protected against would-be predators by the sharp spines incorporated into their fins. In this particular genus, additional protection is afforded by similar projections on the gill covers. This means that they need to be caught with care. It is preferable to steer them into a suitable container, rather than using a net and risking injuring the fish.

WHEN RED BECOMES BLACK

The vivid red colors of squirrelfish make them highly sought after by aquarists, but the real function of the intense color is to camouflage the fish in their natural habitat. Red light does not penetrate well through water, while blue light passes down to the greater depths inhabited by squirrelfish. The absence of red light results in the red fish appearing black, which makes them difficult to spot in the dim water around the reef base. Squirrelfish and soldierfish tend to be more active after dark, so they will not thrive in a brightly lit tank.