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Phylum Porifera


Habitat: marine, in intertidal zones to depths of about 2200m

Syconoid sponge (sycon grade of sponge). The incurrent canals are those which open to the exterior and mark the place where water enters via ostia. The inner portion of the sponge called the spongocoel is lined with celss called choanocytes. What is the function of these cells?

PoriferaCalcareaOrder LeucosoleniidaLeucosolenia

Habitat: On shaded sides and open undersurfaces of rocks, low intertidal zone, subtidal on rocks and boat hulls (marine).

Asconoid sponge (ascon grade of sponge). Symbiotic with many species of protozoans, polychaetes, and crustaceans. More than 100 species of leucosolenia have been described worldwide. What type of spicules does this genus have?

PoriferaCalcareaOrder Leucetta

Habitat: On rock sides, in crevices , on floats and on pilings. Low intertidal to 111m (marine) **collected locally**

Body texture crusty, surface convoluted and bearing many oscules. Oscules can be 15 mm in diameter. Spicules calcareous consisting of large and small rods pointed at both ends. Colony encrusting to about 3cm thick.


Habitat: deep sponges, found at depths ranging from 100m to over 5200m (marine).

"Glass Sponge" "Venus' Flower Basket" Individual sponges often harbor a single pair of shrimp, one of each sex, that enter the sponge when small and reach reproductive adulthood imprisoned together within the spongocoel. Skeletal supports composed of 6-sided spicules of silica (many spicules are fused to form long, thin, glasslike strands).

PoriferaDemospongiaOrder HadromeridaSpheciospongia

Habitat: On shaded rock surfaces and pilings, very low intertidal zone; subtidal to 26m (marine) **collected locally**

"Gray Moon Sponge" A massive, smooth, grey sponge (leathery in texture) with numerous cratter-like oscula on the outer ridge. This sponge can grow to a thickness of 12 inches and may reach 40 inches in length. This sponge may have many commensal organisms.

asconoidsimplest body plan, radially symmetrical, one choanocyte layer, low choanocyte SA/vol therefore the smallest
syconoidmore advanced, bumpy asconoid folded body wall, choanocyte chambers (have many ostia per), increased choanocyte SA/vol therefore more water held therefore larger
leuconoidasymmetrical body, greatly subdivided choanocyte chambers (in current canals connect), highest ratio of choanocyte SA/vol therefore largest
pinacocytemakes epidermis (called pinacoderm)
porocytemakes a hole
mesohylnon living gelatinous middle layer, contains eggs, archaocytes
ostianormally small, many, where water goes in
osculanormally large, few, where water goes out
spongocoelvolume where water collects before it exits the oscula
radial canals
choanocytehas a flagellum, mesh collar, food vacuoles, nuclei; food capture, sperm capture, water movement, gas exchange, waste removal; it is a protest
spiculesskeletal structures, maintain shape, discourage predators, inorganic. calcareous- CaCO3, dissolves in acid, only in Class Calcarea. siliceous- SiO3, glass-like
spongin fibersskeletal structures, maintain shape, organic, acts as fibrous network, only in Class Demospongia
ameobocyteameobocyte (aka archaeocyte) the amazing cells, like sponge stem cells, morph into gametes or other cells, eliminate waste and digest & store food
sclerosponge"coralline sponge", unusually narrow choanocyte chambers, secrete massive calcareous skeleton, leuconoid, restricted to obscure caves and crevices in coral reefs, contains CaCO3, SiO3, and sponging, either Calcarea or Demospongiae
Phylum PoriferaComments