Ianthellide sp. 1.

Diaz, Maria Cristina, Nuttall, Marissa, Pomponi, Shirley A., Ruetzler, Klaus, Klontz, Sarah, Adams, Christi, Hickerson, Emma L. & Schmahl, G. P., 2023, An annotated and illustrated identification guide to common mesophotic reef sponges (Porifera, Demospongiae, Hexactinellida, and Homoscleromorpha) inhabiting Flower Garden Banks National Marine Sanctuary and vicinities, ZooKeys 1161, pp. 1-68 : 1

Ianthellide sp. 1.

Fig. 52

Diagnostic features.

Thin encrusting sponge, <1 mm thick, bright yellow in life, purple in alcohol (Fig. 52A , red arrow). This thin sponge lacked any type of skeleton and seems to be overgrowing the skeleton of a dictyonal hexactinellid skeletal framework (Fig. 52B ). No microscleres could be seen when dissecting and analyzing the skeleton of the hexactinellid, thus it could be dead. The conspecificity of the hexactinellid with Iphiteon panicea sample GFOE3-23, to the right of this yellow sample (GFOE3-23A) could not be identified. The thin sponge appears undetachable from the skeletal framework where it grows. Dark cells similar to verongiid spherulous cells (SC), and granular cells (GC), and wide elliptical choanocyte chambers (CC), 30-80 µm in diameter, support the interpretation of this species as a fiber-less species of the family Ianthellidae (Fig. 52B, C ). This is the first report of a verongiid overgrowing an hexactinellid.

Similar species.

Two Ianthellidae genera without fibers have been described, Hexadella and Vansoestia , which have species with thin bodies, and yellowish color. However, those species have a more detachable leathery body, with surfaces ornamented by dermal canals, and prominent oscula.

Distribution and abundance.

At FGBNMS the species was collected once at Elvers Bank.

Ecology.

Coralline algae reefs, lower mesophotic reefs, algal nodules.

Identification.

MCD.

Reference.

Díaz et al. 2015.

Figures

Figure 52. A In-situ photograph of a thin yellow Verongid growing on an hexactinellid skeletal framework highlighted by the red arrow, 147 m deep. Sample GFOE 3 - 23 A B fragment of sponge observed under light microscope 100 X; arrows show large dark cells potential spherulous cells (SC), and smaller dark cells, potentially granular cells (GC) C smear of a sample fragment observed with a light microscope at 400 x magnification. Note the large ovoid choanocyte chambers (red arrow).