An Eocene conger eel (Teleostei, Anguilliformes) from the Lillebælt Clay Formation, Denmark

A conger eel (Anguilliformes, Congridae) is described from the lower Lutetianconcretionary nodules of the Lillebælt Clay Formation exposed at Trelde Næs,eastern Jutland, based on two partially complete articulated cranial skeletons. Oneof the cranial specimens exhibits an otolith void from which a cast was taken, usedby Schwarzhans (2007) to describe the extinct Pseudoxenomystax treldeensis, whichis placed herein within the new genus Smithconger gen. nov. Smithconger treldeensis(Schwarzhans, 2007) is characterized by well-developed lateral processes on the fron-tals, supraoccipital crest absent, sphenotic spine rather large, anteriorly pointed andexposed on the flattened surface of the skull roof, otic bullae considerably reduced,maxilla almost straight and distally pointed, maxillary and dentary teeth numerousand arranged in multiple rows, dentary with slightly convex ventral profile, operclewith smooth posterior margin and subopercle short. The otoliths of Smithconger trel-deensis show high dorsal rim, broad and deep dorsal depression, no ventral furrow,sulcus straight, shallow, centrally positioned with anteriorly reduced colliculum, andostial channel at anterior tip of colliculum short, not reaching the predorsal rim. Theotolith-based species Bathycongrus waihaoensis Schwarzhans, 2019 from the Kaiatan(Bartonian/Priabonian) of New Zealand is also assigned to the genus Smithconger.Smithconger is tentatively referred to the congrid subfamily Congrinae due to the lackof hypohyals in the hyoid bar. This new Eocene genus of conger eel shows a certaindegree of similarity with the extant Bassanago. The diversity and relationships ofother Eocene congrids is also briefly discussed