Ascidians collected during the 2013 Singapore Strait International Marine Biodiversity Workshop Author Lambert, Gretchen University of Washington Friday Harbor Laboratories, 620 University Road, Friday Harbor WA 98250, USA. Author Lee, Serina Siew-Chen 0000-0001-9326-0941 St John’s Island National Marine Laboratory, National University of Singapore, 18 Kent Ridge Road, Singapore 119227. & serina. lee @ nus. edu. sg; https: // orcid. org / 0000 - 0001 - 9326 - 0941 serina.lee@nus.edu.sg Author Teo, Serena Lay-Ming 0000-0002-3309-4715 St John’s Island National Marine Laboratory, National University of Singapore, 18 Kent Ridge Road, Singapore 119227. & tmsteolm @ nus. edu. sg; https: // orcid. org / 0000 - 0002 - 3309 - 4715 tmsteolm@nus.edu.sg text Zootaxa 2021 2021-02-18 4933 1 1 38 journal article 8063 10.11646/zootaxa.4933.1.1 8ebe62fc-b086-459e-b9fd-8a75ded875c7 1175-5326 4547842 56476487-ABC9-4C1C-A73F-D39E55DB9005 Ecteinascidia thurstoni Herdman, 1890 NEW RECORD Figure 6E Elongate zooids usually pale orange in color, both siphons short, close together at anterior end of body. Orange band around siphons, blue spots in life between the siphons. #2640, longest zooid 10 mm . Orange band around siphons, blue spots in life, not visible in fixed zooids. No orange spots scattered on body wall as in #4613. Sixteen rows of stigmata on right, 17 rows on left. About 50 oral tentacles. Cluster of poorly developed testes in curve of gut in some zooids. #4613, zooids 6 mm in length; a few scattered orange spots on body wall visible through the transparent tunic. Seven oral lobes, six atrial lobes. Sixteen rows of stigmata on right, 15–16 on left (posterior-most row is dividing). A cluster of immature testes in curve of gut. Distribution: Sri Lanka , Australia , Bahrain , Thailand , South Africa , Red Sea, Israel (Mediterranean). Detailed descriptions with illustrations: Kott (1985) , Monniot C. & Monniot F. (1997). Other references: Monniot C. et al . (2001), Gab–Alla (2008) , Chavanich et al . (2009) , Shenkar & Loya (2009) .