macrostomus, Petromyzon Burmeister [H. C. C.] 1868:xxxvi [Anales del Museo Publico Buenos Aires (Acta de la Sociedad Paleontologica Buenos Aires) v. 1; ref. 703] Stream in Buenos Aires (Argentina). Holotype (unique): MACN Ict-12711. Type information: Lacoste et al. 2021:[2] [ref. 38542]. Type locality see Lacoste et al. 2021:[3] [ref. 38542]. •Valid as Exomegas macrostomus (Burmeister 1868) -- (Lacoste et al. 2021:[2] [ref. 38542]). •Synonym of Geotria australis Gray 1851 -- (Fernholm 1990:79 [ref. 21677], Kullander & Fernholm in Reis et al. 2003:11 [ref. 27061], Renaud 2011:16 [ref. 31770]). •Valid as Geotria macrostoma (Burmeister 1868) -- (Riva-Rossi et al. 2020:8 [ref. 37546], Baker et al. 2021:8 [ref. 38327], Miller et al. 2021:[8] [ref. 38264], Riva-Rossi et al. 2022:[3] [ref. 38978], Riva Rossi et al. 2024:[5] [ref. 41014]). Current status: Valid as Geotria macrostoma (Burmeister 1868). Geotriidae. Distribution: Southwestern Atlantic: Uruguay and Argentina, including Falkland Islands and South Georgia (U.K.). Habitat: freshwater, brackish, marine.