Leptoclinides dubius ( Sluiter, 1909 )

Monniot, Françoise & Monniot, Claude, 2001, Ascidians from the tropical western Pacific, Zoosystema 23 (2), pp. 201-383 : 287-288

Leptoclinides dubius ( Sluiter, 1909)

Polysyncraton dubium Sluiter, 1909: 69 . Type locality: Indonesia.

Leptoclinides dubius – Monniot F. & Monniot C. 1996: 176, pl 3H, western Pacific.

MATERIAL EXAMINED. — Papua New Guinea. Louisiades, Calvados Island, Brooker Channel, 11°03.09’S, 152°28.62’E, 12 m (Sample: CRRF).

Leptoclinides madara Tokioka, 1953 ( Figs 69 ; 70 ; 123B )

Leptoclinides madara Tokioka, 1953: 200 , pl. 1, fig. 2; pl. 23, figs 1-6. Type locality: Sagami Bay . — Nishikawa 1990: 116, Japan sea .

MATERIAL EXAMINED. — Palau. Babeldaob, Ibobang, 7°30.58’N, 134°29.66’E, 10 m, 11. VI.1996 ( MNHN A2 LEP 73).

Papua New Guinea. New Ireland, S Coast, outside Kalili Harbour, 3°26.62’S, 151°56.00’E, 15 m, 11.IV.1993 ( MNHN A2 LEP 72). — Milne Bay Province, China Straits, 10°34.50’S, 150°40.73’E, 93 m, 10. VI.1998 (Sample: CRRF).

Philippines. Bohol Sea, Balicasag Island SW of Bohol, 9°31.26’N, 123°41.05’E, 13 m, 16.IV.1997 ( MNHN A2 LEP 74). — Bohol Sea, Balicasag Island SW of Bohol, 9°31.23’N, 123°40.98’E, 22.IV.1997 ( MNHN A2 LEP 76).

DESCRIPTION

The colonies are hard crusts, 5-10 mm thick, irregular in outline and variably pigmented. They have large white and orange patches and irregular black-green specks ( Fig. 123B ). The proportions of these colours are highly variable. The pigments are restricted to the surface layer of the colonies. The zooids are perpendicular to the colony surface.

Both siphons are long, with strong sphincters and without lobes at their rim ( Fig. 69A ). The thoracic musculature is longitudinal with eight to 10 well-spaced bundles. The branchial sac has numerous long stigmata, about 16 in the two first half rows and 15 in the two last half rows. There is no retractor muscle. The lateral thoracic organs are large, in cups at the level of the third transverse vessel. The abdomen is not folded under the thorax ( Fig. 69A ). It has an elongate shape; the oesophagus is long, and the mid-intestine is horizontal in contrast to the vertical foregut and hindgut. The testis follicles ( Fig. 69B ) are arranged in a rosette of three to six follicles with an average of four. They are covered by five to six turns of the sperm duct.

Larvae were present only in a colony from Papua New Guinea. They measure 0.75 mm for the trunk ( Fig. 69C ). They have three anterior adhesive papillae, two pairs of ampullae between them, and one dorsal and one ventral ampulla. On the left side only is an odd anterior protrusion at the base of the ampullae.

The spicules are large and stellate. The rays have chisel-like points; the spicules measure 75 µm for the largest ( Fig. 70 ).

REMARKS

The specimens correspond well to previous descriptions of the species’ colour and the anatomical characters. All Leptoclinides species are so similar in their zooids’ characters that it is difficult to decide if the present specimens belong to Tokioka’s species, but the colour pattern seems characteristic.

L. madara is widely distributed in the western tropical Pacific Ocean.

Figures

FIG. 69. — Leptoclinides madara Tokioka, 1953; A, zooid; B, gonads; C, larva. Scale bar: 0.5 mm.

FIG. 70. — Leptoclinides madara Tokioka, 1953, spicules. Scale bar: 10 µm.

FIG. 123. — A, Atriolum robustum Kott, 1983; B, Leptoclinides madara Tokioka, 1953; C, Leptoclinides subviridis (Sluiter, 1909); D, Diazona formosa Monniot F. & Monniot C., 1996; E, Diazona fungia n. sp.; F, Diazona pedunculata n. sp.