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Kirkpatrickia variolosa (Kirkpatrick 1907)

Description

provided by NMNH Antarctic Invertebrates

"Tedania variolosa, sp, n.

Sponge in form of a mass of thick flabellate or digitate fronds arising from a common base; with circular sphinctrate oscules, each about 1 cm. in diameter, situated at the summits or along the upper edges of the branches, the canals into which they lead extending nearly to the base of the branches. General surface of the sponge covered with circular pore-areas each about 4 mm. in diameter, the oval or circular pores being about 90 µ in diameter, and the strands of the poral reticulum about 30 µ in breadth. Colour in spirit pale brown. Consistence soft and fleshy, being easily torn.

Flagellated chambers, 42 x 3.5 µ L, oval, aphodal, with aphodus (in a measured example) 13 µ long.

Skeleton.—Choanosomal skeleton formed of loosely agglo­merated compound, longitudinal, or main bundles about 1 mm. in diameter, curving out to the surface as they pass upwards; the separate fibres of the main bundles about 80 µ thick. The main bundles joined at right angles by secondary fibres 1-3 spicules thick. Spongin not perceptible. Ecto­somal skeleton formed of circles of strongyles, the spicules isolated or in fan-like wisps, arranged partly vertically, partly tangentially, round the pore-areas; the vertical spicules usually isolated and the tangential ones in wisps. On drying the sponge the edges of the pore-areas stand up sharply, the areas themselves sinking in, giving a pock-marked aspect to the surface.

Spicules.—Megascleres: choanosomal styles, 402 x 13 µ, curved at about one fourth of the length from the round end, smooth, but occasionally with a few spines about the head. Ectosomal strongyles, 261 x 6.5 µ, smooth, occasionally slightly swollen at each end.

Microscleres none.

The single specimen is in the form of a squarish mass of thick fleshy flabello-palmate or digitate lobes; the height is 18 cm. and the breadth 13 cm.

The arrangement of the pores in circular areas each surrounded by a zone of ectosomal spicules is not common in Tedania; it occurs in the second new species described below, and something of the kind is found in Tedania tenuicapitata, Ridley, from the Straits of Magellan. In the present species this feature is so well marked as to give the surface a pock­marked appearance.

The rhaphides, usually so characteristic of Tedania, have entirely disappeared.

Locality. Winter Quarters, 10 fath."

(Kirkpatrick, 1907)