Pararete semperi (Schulze, 1886)

Tabachnick, Konstantin R. & Menschenina, Dorte Janussen And Larisa L., 2008, New Australian Hexactinellida (Porifera) with a revision of Euplectella aspergillum *, Zootaxa 1866 (1), pp. 7-68 : 40-43

Pararete semperi (Schulze, 1886) ( Fig. 18 , 19 ; Tab. 17)

Material. WAM Z 265 — RV Soela , sta. SO 1/84/055, NNW of Lacepede Archipelago, 15 o 57.20‘–59’ S 120 o 46.20‘ –44.60’E, 296– 298 m. WAM Z 584 —NW Caplenque , 224 m. WAM Z 583 — RV Soela , sta. SO 1/ 84/085, NW of Cape Leveque, 14 o 52.20’–53.70’ S 121 o 41.70’ –39.90’E, 220– 224 m. WAM Z 555 — RV Soela , sta. SO 1/84/87, NW of Cape Leveque, 15 o 11.1’–12.90’ S 121 o 26.90’ –25.70’E, 258– 260 m.

Description. Body: Sponges are plexiform, up to 40x30x 30 mm, composed of tubes 6–10 mm in diameter with walls about 0.8 mm in thickness and no channelization.

Framework: The beams of the dictyonal skeleton are 0.023 –0.038 mm with a rough surface. The meshes are 0.08–0.3 mm; they are rectangular at the dermal side and sometimes triangular at the atrial side. The nodes, usually at the dermal side and rarely at the atrial side, are inflated 0.09–0.11 mm in diameter. As usual for dictyonal skeletons of Euretidae , some small hexactins are fixed to the beams; their rough rays with conically pointed outer ends are about 0.046 / 0.006 mm.

A B C

Loose spicules: Dermalia and atrialia are pentactins with rough rays and rounded outer ends. Dermal and atrial pentactins do not differ significantly: The tangential rays of dermal pentactins are 0.092 –0.286 mm, the proximal ray is 0.066 –0.255 mm; tangential rays of atrial pentactins are 0.077 –0.214 mm, the proximal ray is 0.02–0.173 mm; their rays are about 0.006 mm in diameter. Hexactins, normally uncommon for Pararete , are common among the loose choanosomal spicules. They have rough rays 0.02–0.03/ 0.015 mm with conically pointed outer ends. The dermal scopules have smooth tines, lanceolate in shape with a small, single, terminal spine on each of them; these scopules are 0.209–0.536/ 0.002 mm, their 3–4 (sometimes 2 or 5) tines are 0.015 –0.061 mm long. The atrial scopules 0.102–0.291/ 0.002 mm have 4 (rarely 2–6) clavate rough tines, 0.02–0.051 mm long. Uncinates are 0.15–0.7/ 0.002 –0.005 mm.

Microscleres: Exclusively spherical or stellate discohexasters with 4 (rarely 2–6), sigmoidal, secondary rays. They are 0.029 –0.042 mm in diameter with the primary rosette 0.006 –0.015 mm in diameter.

Remarks. Measurements of most spicules do not differ strongly in these two specimens ( Tab. 17). The free choanosomal hexactins commonly found in E. semperi are unusual for the genus.

Aphrocallistidae Gray, 1867

Genus: Aphrocallistes Gray, 1858

Aphrocallistes beatrix beatrix Gray, 1858

Material. WAM Z 247 — RV Soela, sta. SO 1/84/051, NNW of Lacepede Archipelago , 15 o 42.60’S 120 o 37.30’–34.60’E, depth 500– 504 m. WAM Z 242 — RV Soela, sta. SO 1/84/58, NW Beagle Bay , 15 o 12.80’–10.40’ S 121 o 5.90’ –9.20’E, depth 404– 410 m. WAM Z 254 — RV Soela, sta. SO 2/84/057, NW Beagle Bay, 15 o 13.50’–15’ S 121 o 8.90’ –6.50’E, depth 352 m. WAM Z 255 — RV Soela, sta. SO 1/84/065, NW of Cape Leveque, 14 o 49’–50.80’ S 121 o 36.10’ –35.60’E, depth 300­ 302 m. WAM Z 244 — RV Soela, sta.?, NW of Bathurst Island , 14 o 21.50’–22.30’ S 122 o 2.40’ –1’E, depth 348– 350 m. WAM Z 257 — RV Soela, sta. SO 1/ 84/73, NW of Collier , 14 o 10.90’–12.10’ S 122 o 35.10’ –32.10’E, depth 348– 350 m. WAM Z 256 — RV Soela, sta. SO 1/84/91, W of Lacepede Archipelago , 16 o 55.80’– 17 o 1.80’S 119 o 53.90’–51.30’E, depth 426 m. WAM Z 245 — RV Soela, sta. SO 1/84/117, W of Lacepede Archipelago , 16 o 57’–52’ S 119 o 48’ –51’E, depth 450– 452 m. WAM Z 248 — RV Soela, sta.?, W of Lacepede Archipelago , 16 o 54’–59’ S 119 o 52’ –47’E, depth 440 m. WAM Z 557 — RV Soela, sta. SO 2/82/34 B, 20 miles W of W Clarke Reef, 17 o 15’S 119 o 1’E, depth 444– 450 m. WAM Z 274 — RV Soela, sta. SO 2/82/34 B, 20 miles W of W Clarke Reef, 17 o 15’S 119 o 1’E, depth 444– 450 m.

Description and remarks. There are no significant differences in spicule content and dimensions of these fragments compared with those of the specimens described earlier from adjacent locations of the Indonesian Archipelago ( Ijima 1927) and from the Indian Ocean ( Schulze 1895, 1900, 1904). This species is very polymorphous ( Ijima 1927) and investigated material off Australia displays some variability as well: Microscleres with onychoidal outer ends are usually absent, but some specimens have them in considerable numbers. The scopules usually have 4 tines but some specimens have 3–6 tines. All the specimens have large numbers of dermal pentactins with rudimental distal ray beside pinular hexactins.

Lychniscosida Scrammen, 1903

Aulocystidae Sollas, 1887

Genus: Neoaulocystis Zhuravleva, 1962

Neoaulocystis zitteli zitteli (Marshall and Meyer, 1877)

Material. WAM Z 273 — RV Soela , sta. SO 2/82/14, NNW of Port Headland, 18 o 31’–9’ S 118 o 9’ ­8’E, depth 200–201 m.

Description. Body: The sponge is a plexiform globe 90x50x 50 mm, constructed of tubes 10–15 mm in diameter.

Spicules: The lophodiscohexasters, about 0.092 mm in diameter with primary rosette 0.046 mm in diameter, are very rare in this specimen.

Remarks. Features characteristic for N. zitteli zitteli according to Ijima (1927) are present in the investigated specimen; the only difference is that the lophodiscohexasters are a little smaller than described by Ijima (over 0.1 mm in diameter). Nevertheless they are more similar to N. zitteli zitteli than to N. zitteli sibogae (where they are less than 0.057 mm in diameter).

Lyssacinosida Zittel, 1877

Euplectellidae Gray, 1867

Euplectellinae Gray, 1867

Euplectella Owen, 1841

Figures

FIGURE 18. Pararete semperi (Schulze, 1886), WAM Z 265. A, dermal or atrial pentactin. B, choanosomal hexactin. C, uncinate. D; F, scopules with lanceolate tines. E, scopule with clavate tines. G, spherical discohexaster. H, stellate discohexaster.

FIGURE 19. Pararete semperi (Schulze, 1886), WAM Z 265. A, dictyonal skeleton, scale 300 µm. B, scopule with clavate tines, scale 30 mm. C, scopule with lanceolate tines and single terminal spines, scale 10 µm.