Paracaudina tetrapora (H. L. Clark, 1914 )

O'Loughlin, P. Mark, Barmos, Shari & VandenSpiegel, Didier, 2011, The paracaudinid sea cucumbers of Australia and New Zealand (Echinodermata: Holothuroidea: Molpadida: Caudinidae), Memoirs of Museum Victoria 68, pp. 37-65 : 57-61

Paracaudina tetrapora (H. L. Clark, 1914)

Figures 11e, f , 16 , 17

Caudina chilensis . — Joshua, 1914: 6 (part) (non Molpadia chilensis Müller, 1850 ).

Caudina tetrapora H. L. Clark, 1914: 170 , fig. 1.

Paracaudina tetrapora .—H. L. Clark, 1935: 267–284.—H. L. Clark, 1938: 541.—H. L. Clark, 1946: 445.— Pawson, 1977: 119.— Rowe, 1982: 472.— Rowe and Gates, 1995: 265.

Material examined. Western Australia , Perth, Kwinana beach, Oct 1958, WAM Z31886 (1) ; South Cottesloe , 8 Nov 2008, WAM Z31883 (1) . South Australia , Spencer Gulf, Sir Joseph Banks Group, Marum I., sand, 5 m, 8 Jan 1984, SAM K2496 (1) ; St. Vincent Gulf , North Haven to Largs Jetty, seagrass, 1 Dec 1980, SAM K2501 (1) ; Brighton Beach , 14 Feb 1975, SAM K2507 (2) ; off Glenelg , 10 m, 15 Feb 1969, AM J24918 (1) ; mixed localities, Aug 1886, SAM K2485 (2) . Victoria , Westernport Bay, Merricks, 29 Jan 1983, NMV F76565 (1) ; Flinders , beach, Jul 1967, NMV F45259 (1) ; Shoreham , 30 Mar 1902, NMV F45019 (remaining specimen from Shoreham lot 60669–71 / H19 (3) examined in part by Joshua 1914) ; Merricks , beach, Apr 1969, NMV F45274 (1).

Diagnosis. Paracaudina species up to 116 mm total length, up to 24 mm diameter, caudal taper and thin tail combined length 53 mm (preserved; WAM Z31886); firm leathery to parchment-like body wall with slight wrinkling; off-white to cream preserved colour, some yellow to yellowish-red colouration, some phosphatising with yellow colouration around eroding ossicles; posterior body with distinct long caudal taper to narrow rounded end, sometimes tapering to a discrete long thin tail; mid-body ossicles predominantly 4-holed thick buttons, also thick perforated plates and bluntly spinous cups; 4-holed buttons irregularly oval to rectangular, some shallow concave, frequently 4 perforations with 2 large central and 2 small distal, variably thickened and marginally knobbed, up to 48 µm long; some thick irregularly oval to round perforated plates with up to 15 small perforations, margin and surface variably lumpy and knobbed and with blunt pointed projections, rare joining of knobs to create secondary layering, thickened plates up to 72 µm long, more evident in larger specimens; shallow cups with 4 perforations, long blunt thick marginal spines, marginal surface knobs, up to 72 µm long, more evident in larger specimens; ossicles never chilensis -like with central perforation with box and cross bridges.

Type locality. Western Australia, Perth, Cottesloe beach .

Distribution. Southern Australia, from Abrolhos Islands, Western Australia, to Westernport Bay, Victoria; to 10 m.

Remarks. Paracaudina tetrapora (H. L. Clark, 1914) is distinguished amongst Australian species of Paracaudina by having ossicles that are thick knobbed irregularly oval buttons with predominantly 2 large central and 2 distal smaller holes. Joshua 1914 reported two specimens from Victoria as Caudina chilensis (Müller) . Details provided for the larger one (and confirmed here, NMV F169344) indicate that it was Paracaudina cuprea O’Loughlin and Barmos sp. nov. (above). The second specimen (seen here, NMV F45019) was Paracaudina tetrapora (H. L. Clark) . Yellow body wall colouration with phosphatising of ossicles and phosphatic body wall residues is evident in larger specimens. In the largest specimen ( SAM K2507) there is dark red phosphatising of the calcareous ring, and the reddish-brown colouration of the polian vesicle is presumed to be due to phosphatising.

Figures

Figure 11. Photos of preserved specimens of species of Paracaudina (a, c–f): a, P. cuprea O’Loughlin and Barmos sp. nov. holotype (NMV F157396); b, photo of live specimens of P. cuprea including holotype (photo by P. Vafiadis); c, P. keablei O’Loughlin and Barmos sp. nov. holotype (AM J13579); d, P. luticola Hickman, 1962 (NMV F169342); e, P. tetrapora (H. L. Clark, 1914) (from Merricks, Westernport Bay, Victoria; NMV F76565); f, P. tetrapora (H. L. Clark, 1914) (from off Glenelg, South Australia; AM J24918).

Figure 16. SEM images of ossicles from the mid-body wall of a specimen of Paracaudina tetrapora (H. L. Clark, 1914) from Merricks, Westernport Bay, Victoria (NMV F76565).

Figure 17. SEM images of ossicles from the mid-body wall of a specimen of Paracaudina tetrapora (H. L. Clark, 1914) from off Glenelg, St. Vincent Gulf, South Australia (AM J24918).