Microstoma microstoma (Risso, 1810) .

Dusky Pencilsmelt. To 21 cm (8.3 in) TL (Cynthia Klepadlo, pers. comm. to M. L). Circumglobal; subarctic–transitional eastern Pacific to central Baja California (Moser and Butler in Moser 1996). Depth: 0–4,145 m (13,595 ft) (Cynthia Klepadlo, pers. comm. to M.L.). Moser and Butler in Moser (1996) considered at least the eastern Pacific form to be an undescribed species.