ABSTRACT
The genus Lasiognathus was revised by Bertelsen and Pietsch (1996). There are 2 genera, and 4 species recognized in the WCNA: Lasiognathus beebei, Lasiognathus intermedius, Lasiognathus saccostoma, Thaumanichthys binghami, and Thaumanichthys pagidostomus. Distribution for thaumatichthyids; for all Lasiognathus North Atlantic and NE Pacific, and for Thaumamichthys found only in NW Atlantic (Pietsch 2003h). No males for this family have been observed. Metamorphosed females SL; Lasiognathus beebei 11.2 cm, Lasiognathus intermedius 12.9 cm, Lasiognathus saccostoma 7.7 cm, Thaumanichthys binghami 29.4 cm (Pietsch 2003h). Thaumatichthyids are a family of elongate ceratioids resembling the Oneirodidae with an upper jaw extending beyond the lower. It is represented by 2 genera, Thaumatichthys and Lasiognathus. This family is believed to possess free-living, nonparasitic males. No spent females or females with obvious denticular teeth scarring have been observed. Larvae are sexually dimorphic. Sexual dimorphism of the illicium is evident in the genus Thaumatichthys. No larval Lasiognathus have been observed to date. Four larvae (3-18 mm) and one free-living male of the Thaumaticthys pagidostomous have been described, (Bertelsen 1951, Bertelsen & Stuhsaker 1977, Bertelsen & Pietsch 1996).
