Picton & Goodwin, 2007
Lissodendoryx (Ectyodoryx) jenjonesae Picton & Goodwin (2007) is a yellow encrusting sponge with prominent raised surface areolae. It differs from other Lissodendoryx species from the area in having strongyles as ectosomal spicules and the sigmas are lacking. It was recently described from Rathlin Island, Northern Ireland, but may also be represented by shallow-water records of Lissodendoryx (Ectyodoryx) atlantica (Stephens, 1920).
Shape, size, surface an dconsistency: Yellow crust with prominent pore sieves with raised edges. Patches can be quite large (>10 cm maximum diameter).
Spicules: Megascleres: Primary acanthostyles 500-550 by 5-10 µm. A few very thin individuals (2 µm). Most do not have any development of the head, and appear completely smooth under the light microscope, although a few very small spines are usually present around the head when viewed under SEM. In a few individuals the head is very slightly tylote and the spines are more pronounced. Secondary acanthostyles 110-150 by 5-7 µm. Head heavily spined, shaft less densely so. Head not tylote. Ectosomal spicules strongyles 375-420 by 2-5 µm. Usually asymmetrical, tapering from a thicker end to a thinner one. One or both ends may be swollen. Microscleres: Chelae arcuatae, 30-40 µm.
Skeleton: The choanosomal skeleton consists of a loose reticulation of columns of primary acanthostyles, 3-10 spicules in width, which arise from a basal layer of spongin. These columns are sparingly echinated by secondary acanthostyles, these are rare and occur mainly adjacent to the spongin at the base of the columns. Chelae are present in small numbers throughout the tissue. The ectosomal skeleton consists of a layer of ectosomal strongyles and a dense layer of chelae. The edges of the pore sieves are supported by columns of the ectosomal spicules.
Distribution: Known from the type locality, Rathlin Island, and off the Hebrides; possibly Roscoff.
Ecology: Deeper water (28 m downward to more than 100 m), on cliffs, rocks and Lophelia.
Etymology: Named after Jen Jones of the Rathlin Island sponge project.
Type specimen information: Holotype Mc2742, White Cliffs, Rathlin Island, Northerrn Ireland.
This species can be separated from other Lissodendoryx (Ectyodoryx) species by the lack of sigmas. Although the form of the spicules and the lack of sigmas is superficially similar to those of Lissodendoryx (Ectyodoryx) atlantica (Stephens, 1921), the spicule sizes are substantially different: the primary acanthostyles, tornotes and chelae are much shorter. Additionally, the strongyles in atlantica tend to be symmetrical and not swollen at the ends, the large acanthostyles mainly have tylote heads and the chelae have very broad shafts. The chelae of jenjonesae have a proportionally longer shaft compared to the alae than atlantica, and the alae tend towards being palmate with more of the edge joined to the shaft, whereas in atlantica they are clearly separated. The spicule sizes of our specimens agree with those given by Cabioch (1968) for a specimen of L. (E.) atlantica and it may be that his specimen is actually L. (E.) jenjonesae.
Source: Picton & Goodwin, 2007.