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 Rhopalaea crassa ( Herdman, 1880 ) Figure 1B #0150, one; #1191B, thorax only; #1226; #3786, three; #4617, one, 5.3 cm in length. This species is always solitary, the thorax yellow, with the abdomen embedded in crevices or coral rubble and with only the thorax protruding in its thick opaque bright yellow tunic. Thus collected specimens are often broken off at the narrow neck between thorax and abdomen and only the thorax is collected. Widely distributed in the tropical west Pacific including Indonesia , Hong Kong , Philippines , Singapore , Sri Lanka , Japan , Mozambique , Papua New Guinea , Guam . Detailed descriptions with illustrations: Monniot C. (1997b), Monniot F. & Monniot C. (2001), Lee et al . (2013) . Other references: Van Name (1918) , Millar (1975) , Kott & Goodbody (1982) , Kott (1990 , part; 1992), Nishikawa (1991) , Lambert (2003) , Lee et al . (2016) .