(Figs. 4–6)
Ortholaba tenuis Townes, 1969: 129; Yu & Horstmann, 1997: 459.
Diagnosis. Distinguished from O. laevis by any of the following: Clypeus, mandible and hind coxa black. Front and middle coxae yellowish white. Face with dense and distinct punctures on its central portion. Lower portion of mesopleuron with dense and distinct punctures.
Materials examined. 2 ɗɗ, JAPAN: Honshu, N 35 º 32 ', E 135 º 25 ', 2003. V. 17, R. Matsumoto (OMNH), 2 ΨΨ, JAPAN: Honshu, N 34 º 21 ', E 135 º 29 ', 2003. VI. 6, R. Matsumoto (OMNH).
Distribution. Japan and Russia.
Remarks. See the remarks on O. laevis sp. nov.