Protanguilla palau (Johnson et al. 2011; 18cm) is a newly discovered 'living fossil" from the depths of the sea, seemingly basal to all eels. Distinct from eels, Protanguilla has gill rakers, fewer than 90 vertebrae, pterotic does not approach anterior margin of pterosphenoid, and the latter bone participates in the posterior margin of the orbit. Eels are traditionally associated with Elops. Albula and Megalops. The LRT does not support that hypothesis of interrelationships. Here Protanguilla is a derived sister to Anguilla. Note the upturned lower lip contrasting with the downturned anterior dentary. A tooth carpet of upper and lower teeth is present.

Sapperichthys chiapanensis (Amaral et al 2013, Cenomian, Late Cretaceous, 90mya, 15 cm est length) is an early gonorynchid, derived from Late Cretaceous Pentangmius and basal to European eels (Anguilla). Fossil in situ shown actual size.

Gonorynchus gonorynchus (originally Cyprinus gonorynchus Linneaus 1766; 60 cm) has several common names including beaked salmon, ratfish, mousefish, sand eel, sand fish and shark whiting. The circumorbital bones are absent. The jaw elements lack teeth. This nocturnal fish eats zooplankton and buried invertebrates, then buries itself during the day.

Gregory 1933 reported, "It has an elongate cylindrical body and a sturgeon-like head with a pointed snout, a small inferiorly-placed mouth and a rostral barbel. The body and head are covered with small spiny scales."

Here several bones labeled in Gregory 1933 are relabeled according to Pentanogmius and European eel (Anguilla) homologs. A notochord pierces the well-ossified abdominal vertebrae. The torso is squarish in cross-section. The pectoral fins are essentially immobile.

A postorbital is absent. The prefrontal is separated from the postfrontal. The tail is diphycercal. The prefrontal sits atop a segment of the postfrontal.

Anguilla anguilla (Linneaus 1758; up to 80cm in length, 1.5 exceptionally) is the extant European eel, a sister to the cusk eel in the LRT.Anguilla lacks several facial bones, pelvic fins and the tail has reverted to a straight tail.

The life cycle includes breeding and young hatching in the mid-Atlantic with migration back to European rivers before the adults return to the mid-Atlantic. Bones are relabeled here based on sister taxa.