The genus was described by Chandler in 1935 who gave it a new genus as it was the only genera in the family Neoechinorhynchidae with more than four horizontal rows of hooks on the proboscis apart from Tanaorhamphus (which has a large and long proboscis with 20 or more transverse rows of large hooks and a body that is cylindrical or enlarged anteriorly) and Pandosentis (which has a short cylindrical proboscis with hooks that are not U-shaped but bent at right angles, very short lemnisci, and short retractor muscles).

[1] Phylogenetic analysis has been performed on A. duranguensis [2] Atactorhynchus species consist of a proboscis covered in very irregularly arranged hooks and a trunk.

The hooks are U-shaped, with large rod-shaped roots and slender spines with only the tips projecting through the cuticle.

The syncytial cement gland, which are used to temporarily close the posterior end of the female after copulation, are in contact with testes.

A. duranguensis has been found in the intestine of the Mezquital pupfish (Cyprinodon meeki) from in-land near Durango, Mexico.

[3] A. verecundus was found in the intestines of about 30 to 40 percent of the sampled Sheepshead minnow (Cyprinodon variegatus) in upper parts of Galveston Bay in very large numbers in some hosts.

The hooks are U-shaped, with broad, bluntly rounded roots and slender sharp points, with only the tips projecting through the cuticle.

The seminal vesicle is rounded, dorsal to anterior end of cement reservoir, and connected with genital aperture by two ducts.

This stage involves penetrating the wall of the mesenteron or the intestine of the intermediate host and growing.

There are no reported cases of Atactorhynchus infesting humans in the English language medical literature.