Identifying Sponges

Key to California Porifera (Page 206)

( From page 205 A) Sterrasters absent.
[A]
Megascleres = Oxeas, Anatriaenes, Orthotriaenes, Plagiotriaenes, and Dichotriaenes.
cc206A.jpg
Stelletta clarella de Laubenfels, 1930
Sponge: Encrusting to 4 cm thick to massive. Consistency: spongy to cartilaginous. Surface: superficially hispid.
Color: Alive: White or grey to dark brown.
Spicules: Megascleres: (1) Oxeas: 1400 um. x 15 um. (2) Oxeas: 3500 um. x 50 um. (3) Anatriaenes: Rhabds 1100 - 2000 um. x 9 - 15 um. Chords 45 - 90 um. (4) Orthotriaenes: Rhabds 2000 um. x 20 um. (5) Plagiotrianes: 3000 um. x 100 um. (6) Dichotriaenes: Chords 120 - 180 um. Microscleres: (1) Oxyasters: 7 - 15 um. (2) Irregular Oxyspherasters: 3 - 5 um. Tufts of spines at the end of each thick ray; look like irregular grains under the light microscope.
Skeleton: Ectosome: Cartilaginous cortex packed with clads of Dichotriaenes. Choanosome: Radiate,with fascicular columns of spicules perpendicular to the surface.
Distribution: Southern to Northern California.
Depth: Intertidal to deep water.
[B]
Megascleres = Oxeas, Plagiomonaenes-Diaenes or Triaenes.
Stelletta estrella de Laubenfels, 1930
Sponge: Subspherical to massive to 5 cm thick. Surface: superficially hirsute. Oscula: inconspicuous, 1 mm in width.
Color: Alive: White.
Spicules: Megascleres: (1)Oxeas: 2600 - 4000 um. x 45 - 100 um. (2)Plagiomonaenes-Plagiodiaenes-Plagioriaenes: Rhabds 4000 um. x 9 - 78 um. Chords 35 - 200 um. Microscleres: (1)Oxyspherasters: 2.5 -12 um. (2)Tylospherasters: 10 - 11 um.
Skeleton: Ectosome: Cortex, cartilaginous, hyaline, dense with few Asters and transversed by megascleres. Spicule fur, 1-3 mm high with clads far out from sponge surface. Choanosome: Radiate.
Distribution: Southern California.
Depth: Intertidal to deep water.
Note: May be a synonym of S. clarella. See Bakus & Green, 1987 where S. estrella is considered a southern California variety and S. clarella the central and northern California variety of the same species.
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