Page 296 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

294 MARINE INVERTEBRATES DIRECTORY

MOLLUSKS AND ANNELIDS

There are few more diverse invertebrate groups than
the mollusks. Marine gastropod mollusks possess a
protective shell and a “foot” for locomotion, just like
the land snails. Bivalves, such as clams, have a two-part,
hinged shell and a more sedentary lifestyle. The
shell-less sea slugs can be difficult to maintain in
aquariums, because their dietary requirements
are so specific. Cephalopods, which include
squid and octopuses, can also be problematic,
since they require large tanks and are extremely
sensitive to water conditions. Annelids, in
contrast, are a group of segmented worms.
The Spanish Dancer (Hexabranchus imperialis) is the
largest and also one of the most attractive of all sea slugs,
thanks to its vivid red-and-white coloration. Originating
from the Indo-Pacific, it has a graceful swimming motion.

Limaria scabra Tridacna crocea
Flame Scallop Crocus Clam High-intensity lighting is vital for the well-being
of this clam. The blue coloring is produced by
ORIGINS Widely distributed throughout the Caribbean ORIGINS Southeast Asia, originating from the coastal algae living in the mantle (the inner lining of the
region, and in parts of the western Atlantic. waters around Singapore and parts of Indonesia. shell), and these microorganisms need bright light
SIZE 2 ⁄2 in (6 cm) in diameter. SIZE 8 in (20 cm). in order to be able to carry out photosynthesis,
1
DIET Filter-feeding. Provide a prepared food or a blend DIET Filter-feeding and symbiosis. Needs fine particulate which provides the clam with most of its nutrients.
of puréed shellfish and seawater. food and good lighting to maintain its internal algae. A healthy clam will not only be well colored, but
WATER Temperature 77–79°F (25–26°C); alkaline WATER Temperature 77–79°F (25–26°C); alkaline will also be able to close rapidly when touched
(pH 8.1–8.3) with SG 1.020–1.024. (pH 8.1–8.3) with SG 1.020–1.024. gently with a finger. Crocus Clams obtain some of
their food by filtering tiny creatures from seawater,
The true beauty of this scallop is only apparent Its stunning blue interior, emphasized by the which is drawn into the body via an opening called
when it opens its shell and exposes the scarlet-red external fluting, makes this small, slow-growing an inlet siphon. Prepared foods for filter-feeders
interior and tentacles. (One closely related form bivalve a popular choice for the invertebrate tank. enable Crocus Clams to feed well in aquariums.
has off-white tentacles.) Flame Scallops anchor
themselves to rockwork, so place them near the
front of the tank where they will be clearly visible.
They may breed successfully in the tank, giving
rise to small groups of young.

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