metriostoma, Sirembo Vaillant [L. L.] 1888:270, Pl. 23 (figs. 3-3b) [Expéditions scientifiques du "Travailleur" et du "Talisman"; ref. 4496] Banc d'Arguin, depth 1230 meters; Azores, northeastern Atlantic, depth 1442 meters. Holotype: MNHN 1886-0519. Syntypes: MNHN 1886-0521 (1), MNHN (1, lost). •Valid as Monomitopus metriostoma (Vaillant 1888) -- (Nielsen & Nybelin 1963:195 [ref. 5094], Nielsen 1973:551 [ref. 6885], Cohen 1981:1090 [ref. 8491], Carter & Cohen 1985:86 [ref. 5145], Nielsen in Whitehead et al. 1986:1163 [ref. 13677], Nielsen 1990:570 [ref. 16246], Santos et al. 1997:53 [ref. 23531], Arruda 1997:109 [ref. 24952], Nielsen & Cohen in Nielsen et al. 1999:78 [ref. 24448], Nielsen 2016:1951 [ref. 34583], Carneiro et al. 2019:158 [ref. 37250], Reiner 2019:111 [ref. 38139] as metriosma, Fermon et al. 2022:207 [ref. 39448], Girard & Johnson 2024:6 [ref. 41368]). Current status: Valid as Monomitopus metriostoma (Vaillant 1888). Ophidiidae: Neobythitinae. Distribution: Eastern Atlantic: Portugal and southern Spain south to Angola, including Azores, Canary Islands, Cape Verde Islands, and São Tomé and Principe. IUCN (2015): Least Concern. Habitat: marine.