Eptatretus grouseri McMillan, 1999: 114 Eptatretus grouseri Mok et al. , 2001: 1026 Mincarone & McCosker, 2004: 164 Fernholm & Quattrini, 2008: 126 McCosker & Rosenblatt, 2010: 172 Knapp et al. , 2011: 404 Ruiz et al. , 2011: 30 Cruz-Mena & Angulo, 2015: 325 Angulo & Del Moral-Flores, 2016: 103 Mincarone, 2017: 802 Eptatretus Eptatretus grouseri Møller & Jones, 2007: 63 Review of the hagfishes (Myxinidae) from the Galapagos Islands, with descriptions of four new species and their phylogenetic relationships Mincarone, M. M. Plachetzki, D. McCORD, C. L. Winegard, T. M. Fernholm, B. Gonzalez, C. J. Fudge, D. S. Zoological Journal of the Linnean Society 2021 192 453 474 6FZ3R MCMILLAN, 1999 McMillan 1999 [880,1353,1041,1066] Myxini Myxinidae Eptatretus Animalia Myxiniformes 8 461 Chordata species grouseri  ( FIGS 1, 2C; TABLES1–3)      Eptatretus grouseri  McMillan, 1999: 114, fig. 2a [original description; type locality: Galapagos Islands, 00°14.6’S, 91°26.6’W,  2370 ft(  722 m); type series: holotype, CAS 86428; paratype, SIO 97-77(1)].    Eptatretus grouseri. –  Mok et al., 2001: 1026. –  Mincarone & McCosker, 2004: 164, figs 2, 3b. –  Fernholm & Quattrini, 2008: 126. –  McCosker & Rosenblatt, 2010: 172. –  Knapp et al., 2011: 404. –  Ruiz et al., 2011: 30. –  Cruz-Mena & Angulo, 2015: 325. –  Angulo & Del Moral-Flores, 2016: 103. –  Mincarone, 2017: 802.    Eptatretus Eptatretus grouseri.–  Møller & Jones, 2007: 63.   Material examined:  CAS86428, holotype( 370 mm), NE Fernandina Island, Punta Espinosa, 00°14’36”S, 91°26’36”W,  722 mdepth, submersible  Johnson Sea Link, baited minnow trap, J. E. McCosker,  R. G. Gilmore,  17 November 1995.  SIO 97-77(ex CAS86428), paratype, 1( 138 mm), taken with holotype.  CAS 201882, 2( 315–420 mm), Seymour Island, 00°21’42”S, 90°15’00”W,  648 mdepth, submersible  Johnson Sea Link, baited minnow trap, C. Baldwin, J. E. McCosker,  25 July 1998.  Diagnosis: Eptatretus grouseridiffers from all congeners, except  E. aceroi Polanco-Fernandez & Fernholm, 2014from Colombia,  E. profundus( Barnard, 1923)from South Africa,  E. wandoensis Song & Kim, 2020from South Koreaand  E. wayuu Mok et al., 2001from Colombia, by having five pairs (six pairs in one specimenof  E. grouseri) of gill apertures arranged in a straight line and a 3/2 multicusp pattern of teeth.  Eptatretus grouseridiffers from these fivegilled congeners by having: 44–48 total cusps (vs. 58 in  E. aceroi, 40–43 in  E. wandoensisand 41–43 in  E. wayuu); 11–12 prebranchial pores (vs. 44 in  E. aceroi, 14–18 in  E. wandoensisand 24 in  E. wayuu); 42–48 trunk pores (vs. 107 in  E. aceroi, 48–51 in  E. profundusand 38–40 in  E. wayuu); 13–15 tail pores ( 9–11 in  E. wandoensis); 71–79 total pores (vs. 174 in  E. aceroiand 81–86 in  E. profundus) ( Mok et al., 2001; Polanco-Fernandez & Fernholm, 2014; Mincarone, 2017; Song & Kim, 2020).  Description:Body morphology, measurements and counts provided by McMillan (1999)and Mincarone & McCosker (2004).  Distribution and habitat: Galapagos Islands: known from four specimenscollected in two localities: off Fernandina Island (Punta Espinosa), at 722 mdepth, and off north-eastern Seymour Island, at 648 mdepth ( Fig. 1). CAS 86428 [1067,1329,1169,1191] CAS 722 -0.24333334 Galapagos Islands 130 -91.44334 8 461 SIO 97-77 2 Galapagos holotype CAS 86428 CAS NE Fernandina Island & J. E. McCosker 722 -0.24333334 Punta Espinosa 21 -91.44334 8 461 1 holotype 1995-11-17 R 8 461 1 holotype CAS 86428 CAS 8 461 SIO 97-77 2 paratype 1998-07-25 CAS C. Baldwin & J. E. McCosker 648 -0.36166665 Seymour Island 21 -90.25 8 461 CAS 201882, 2 1 paratype