diagrammus, Eutyx Heller [E.] & Snodgrass [R. E.] 1903:224, Pl. 19 [Proceedings of the Washington Academy of Sciences v. 5; ref. 2089] Tagus Cove, Isabela Island [Albemarle Island], Galápagos Islands, depth about 3 fathoms. Holotype: CAS-SU 6346. Paratypes: CAS-SU 7059 (1). Type catalog: Böhlke 1953:101 [ref. 12291]. •Valid as Oligopus diagrammus (Heller & Snodgrass 1903) -- (Cohen & Nielsen 1978:49 [ref. 881], Eschmeyer & Herald 1983:103 [ref. 9277], Allen & Robertson 1994:77 [ref. 22193], Grove & Lavenberg 1997:222 [ref. 24023], Richards & Engle 2001:181 [ref. 25759]). •Valid as Grammonus diagrammus (Heller & Snodgrass 1903) -- (Nielsen & Cohen in Nielsen et al. 1999:104 [ref. 24448], Thomson et al. 2000:53 [ref. 25640], Nelson et al. 2004:92 [ref. 27807], Nielsen & Cohen 2004:85 [ref. 28073], Love et al. 2005:52 [ref. 37547], Castellanos-Galindo et al. 2006:199 [ref. 28944], Nielsen 2007:375 [ref. 29358], Nielsen & Prokofiev 2010:192 [ref. 30790], McCosker & Rosenblatt 2010:190 [ref. 30957], Page et al. 2013:95 [ref. 32708], Møller et al. 2016:Appendix A [ref. 34432] in Bythitidae, Fourriére et al. 2016:442 [ref. 34668], Del Moral-Flores et al. 2016:607 [ref. 34923], Love et al. 2021:84 [ref. 39279]). Current status: Valid as Grammonus diagrammus (Heller & Snodgrass 1903). Bythitidae. Distribution: Eastern Pacific: southern Califoria (U.S.A.) south to Ecuador, including Gulf of California (Mexico), Revillagigedo Islands (Mexico) and Galapagos Islands (Ecuador). Habitat: marine.