The number of the ANA grew to around 20,000 in 2005, most of which were trained by forces of the United States.
"Pterygotus impacatus" Kjellesvig-Waering, 1964 — Silurian, Estonia*"Pterygotus kopaninensis" Barrande, 1872 — Silurian, Czech Republic*"Pterygotus lanarkensis" Kjellesvig-Waering, 1964 — Silurian, Scotland*"Pterygotus lightbodyi" Kjellesvig-Waering, 1961 — Silurian England*"Pterygotus ludensis" Salter in Huxley & Salter, 1859 — Silurian, England*"Pterygotus marylandicus" Kjellesvig-Waering, 1964 — Silurian, USA*"Pterygotus monroensis" Sarle 1902 — Silurian, USA*?