The Westpalaearctic Lasius paralienus complex (Hymenoptera: Formicidae) contains three species.

Application of Numeric Morphology-Based Alpha-Taxonomy (NUMOBAT) demonstrated the existence of three cryptic species within the Westpalaearctic Lasius paralienus species complex: L. paralienus Seifert, 1992, having a wider European distribution north to Sweden, L. casevitzi sp.

What is Tetramoriumsemilaeve André, 1883? (Hymenoptera, Formicidae).

Tetramoriumsemilaeve André, 1883 is redescribed based on the type series and new material from terra typica (Pyrénées-Orientales). Lectotype worker is designated. Detailed descriptions of gyne and male are given.