Ascidians from the tropical western Pacific Author Monniot, Françoise Author Monniot, Claude UPESA 8044, Laboratoire de Biologie des Invertébrés marins et Malacologie, Muséum national d’Histoire naturelle, 55 rue Buffon, F- 75005 Paris (France) monniot @ mnhn. fr. monniot@mnhn.fr text Zoosystema 2001 23 2 201 383 journal article 10.5281/zenodo.5391440 1638-9387 5391440 Atriolum robustum Kott, 1983 ( Fig. 123A ) Atriolum robustum Kott, 1983: 15 , figs 1-4. Type locality: Northern Australia . — Millar 1988: 830 , fig. 3, Madagascar . — Lafargue & Vasseur 1989: 61 , fig. 2, Mayotte , Mauritius . — Monniot F. 1990b: 676, fig. 2, pl. IB, New Caledonia . MATERIAL EXAMINED . — Papua New Guinea . Louisiade Archipelago, Calvados Island Chain, Brooker Channel, 11°03.09’S , 152°28.62’E , 7 m , 1. VI .1998 ( MNHN A2 ATR 15). REMARKS The colonies are made of several urn-shaped lobes on a common base. The colour is a mixture of green, pink, and light brown with white rims of the large common cloacal apertures ( Fig. 123A ). Symbiotic algae are present in the tunic. All characters agree with previous descriptions. No larvae were found in this material. The distribution of this species is wide in both the western Pacific Ocean and in the Indian Ocean.