Polysyncraton (Ascidiacea, Didemnidae): a re-examination of some specimens and descriptions of three new species Author Oliveira, Livia M. 2058206A-50D4-4956-8888-358701793D7F Laboratório de Sistemática e Ecologia de Invertebrados Marinhos, Departamento de Zoologia, Universidade Federal do Paraná, CP 19020, 81531 - 980 Curitiba, Brazil. liviaoliveira@ufpr.br Author Hoeksema, Bert W. 548DBAFD-040B-4773-A043-6FCC466160A1 Department of Taxonomy and Systematics, Naturalis Biodiversity Center, P. O. Box 9517, 2300 RA Leiden, the Netherlands. bert.hoeksema@naturalis.nl Author Rocha, Rosana M. E170DE7A-DB70-4E5B-8488-45FA680812DA Laboratório de Sistemática e Ecologia de Invertebrados Marinhos, Departamento de Zoologia, Universidade Federal do Paraná, CP 19020, 81531 - 980 Curitiba, Brazil. rmrocha@ufpr.br text European Journal of Taxonomy 2019 2019-04-23 519 1 25 journal article 26985 10.5852/ejt.2019.519 c6f362bc-4d6b-4e3a-b69a-a9e8392e6756 2118-9773 2650112 D9E64DD6-D675-4E25-B9B8-A44C14CE0B22 Polysyncraton purou C. Monniot & F. Monniot, 1987 Fig. 10 Polysyncraton purou C. Monniot & F. Monniot, 1987: 49 , fig. 16d–h, pl. 3i. Polysyncraton purou – F. Monniot 1993: 11 . — Kott 2001: 126 , figs 60, 162C, pl. 6F; 2002: 33, fig. 12A– D; 2005: 2436, fig. 19D. Material examined TANZANIA • 3 slides; MNHN A2-843, MNHN A2-846, MNHN A2-847. Remarks This species was described from French Polynesia by C. Monniot & F. Monniot (1987) . All the characteristics of the specimens from Tanzania correspond to those in the original description ( Fig. 10 ), thus enlarging the known distribution of this species. Monniot & Monniot (2001) described P. vestiens from Palau as a different species from P. purou based on the smaller spicules, a wider atrial aperture and the absence of the muscular process in P. vestiens . However, in the specimens from Tanzania there is a variation in the size of the spicules and they are smaller ( 43 to 55 µm ) than in specimens from Tahiti. The muscular process in P. purou is very small and not visible in some zooids ( Fig. 10 a–b). Since the size of the atrial aperture is also a variable character that depends on the contraction of the zooid, there is doubt as to whether P. vestiens is a valid species. Distribution Type locality: French Polynesia (C. Monniot & F. Monniot 1987 ). Australia ( Kott 2001 ), New Caledonia (F. Monniot 1993 ) and Tanzania (this study).