(Fig. 5, video 4)
Gnathophylloides mineri — Brinkmann & Fransen 2016: 438 (Curaçao); Faasse 2016: 52 (Sint Eustatius); Poupin 2018: 106 (Sint Maarten).
Material examined. Curaçao: RMNH. CRUS.D.27600: 1 male pocl. 1.2 mm; Piscaderabaai, Boca, 05.i.1964, depth 1–2 m, san, gravel, collected by P.Wagenaar Hummelinck no. 1457. RMNH. CRUS.D.58081: 1 ovigerous female; stn COA. 01, Hilton Reef, 12°07′18.44″N 68°58′10.23″W, 07.xi.2013, snorkeling, depth 1 m, on Lytechinus variegatus (Lamarck, 1816), collected by C.H.J.M. Fransen (photo COA.01 196–198, 206–219). RMNH. CRUS.D.58082: many specimens; stn COA.03, W Piscadera Baai, 12°07′21.90″N 68°58′13.54″W, 02.xi.2013, depth 1 m, on Tripneustes ventricosus (Lamarck, 1816), collected by C.H.J.M. Fransen. RMNH. CRUS.D.58083: 6 specimens; stn COA. 14, Playa Boka Sami, 12°08′51.40″N 68°59′55.50″W, 05.xi.2013, scuba diving, depth 5 m, on L. variegatus collected by C.H.J.M. Fransen (photo COA.14 128–132). RMNH. CRUS.D.58084: 11 specimens; stn CF19B-3, Cas Abou, 19.vi.2017, scuba diving, depth 3 m, on T. ventricosus, collected by C.H.J.M. Fransen (video 4). Bonaire: RMNH. CRUS.D.58085: 13 specimens; stn BON.16, Tailor Made, 12°13.407′N 068°24.223′W, 29.x.2019, snorkeling, depth 2 m, on T. ventricosus, collected by Werner de Gier. RMNH. CRUS.D.58086: 3 specimens; stn BON.18, Red Slave, 12°01.605′N, 068°15.079′W, 28.x.2019, snorkeling, depth 2 m, on T. ventricosus, collected by Werner de Gier.
Ecology. Symbiont of shallow water regular sea urchins. In the western Atlantic recorded from L. variegatus and T. ventricosus (Marciá & Robinson 2009; Tavares et al. 2017; Vera-Caripe et al. 2017).
Distribution. Disjunct circumtropical, being absent from the central and eastern Atlantic, widely distributed in the western Atlantic from Florida south to Bahia, Espírito Santo and Trindade Island, Brazil (Chace 1956; De Grave & Anker 2017; Vera-Caripe et al. 2017; Tavares et al. 2017; Poupin 2018). This is the first record of the species from Bonaire.
Genus Gnathophyllum Latreille, 1819