Invertebrate-Sponges

Porifera
Sponges are the most primitive of the multicellular invertebrates. Their bodies have a system of water canals. These canals enable them to eat, breate, reproduce, and excrete through pumping water through their bodies. They come in many colors such as yellow, blue, and orange. Sponges have spicules that look like little spikes or stars. Scientists utilize this trait as a way to identify which species they belong to.

*Sponges belonging to the family Cladorhizidae are extremely unique considering that they feed by catching then digesting whole animals. These are the few carnivorous sponges in the world.

Poriferans have holes in their outer walls that draw in water. They filter particles in the water, which enables them to receive food.

Sponges can reproduce asexually and sexually. Most sponges that reproduce sexually are hermaphroditic (they produce eggs&sperm at separate times). Sperm is created then sent out through the openings of the sponge. They then are captured by the female sponges of that particular species. The female then transports the eggs by archaeocytes (cells). Sponges that reproduce asexually produce gemmules or buds. They are a bunch of cells inside a protective shell or cover.

Carnivorous sponge

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Asbestopluma hypogea

ORDER Poecilosclerida

FAMILY Cladorhizidae

OTHER COMMON NAMES French: Éponge carnivore.

PHYSICAL CHARACTERISTICS Small white sponge with an ovoid body as large as 0.25 in (6.5 mm) high and 0.04 in (1.2 mm) thick, attached to the substrate with a long, thin stalk up to 0.5 in (14 mm) long and .007 in (0.18 mm) in diameter. The body bears 30–60 filaments up to 2.3 in (60 mm) long and 50–80 µm in diameter. The filaments are sticky and shaggy because of their dense cover of tiny raised hook-shaped microscleres (anisochelae).

DISTRIBUTION Known from two caves near Marseille, France, and one in La Croatia, (Mediterranean).

HABITAT Rocky surfaces in caves where water is trapped all year long and thus has a constant low temperature of 55-58° F (13–14.7°C), 50-195 ft (15–60 m) away from the entrance, at a depth of 55-75 ft (17–23 m).

BEHAVIOR Their carnivorous feeding behavior makes these sponges unique.

FEEDING ECOLOGY AND DIET These sponges have no aquiferous system or choanocyte chambers. Their diet consists of small crustaceans that they capture in their filaments. The prey is completely surrounded by new filaments and digested within a few days.

REPRODUCTIVE BIOLOGY Viviparous; however, little is known as of 2003 regarding the exact time of reproduction and structure of the embryos.

CONSERVATION STATUS Known only from La Ciotat; protected under the Bern Convention of 1998 due to its patrimonial interest.

SIGNIFICANCE TO HUMANS None known.

*Research is being done on sponge's chemicals that keep bacteria from over-growing on them. Scientists have found these chemicals are powerful antibiotics that may help prevent or cure some diseases. Leukemia, arthritis, and strep throat are among the diseases that the sponges' chemicals may help to cure. Scientists hope that they will soon be ready for human use.