Leptothorax caesari Espadaler, 1997c: 146, figs. 1-6 (w.q.m.) SPAIN. Palearctic.

Primary type information: Type-material: holotype worker. Type-locality: Spain: Huesca Prov., 20 m., from Sariñena lagoon, 11.v.1980 (X. Espadaler). Type-depository: XEPC. Secondary type information: Paratype-material: 38 paratype workers, 15 paratype queens, 15 paratype males. Paratype-locality: 5 paratype workers with same data as holotype but 10.ii.1983, 24.ii.1983, 7.iv.1983, 20.iv.1983, 16.vi.1983, pitfall traps, 1 paratype queen with same data as holotype but 14.iv.1983 (C. Pedrocchi), 18 paratype workers, 1 paratype queen with same data as holotype but 19.iv.1985, + 6 paratype queens, 1 paratype male eclosed in laboratory, viii.1985 (X. Espadaler), 14 paratype workers, 1 paratype queen with same data as holotype but 8.ix.1987, + 6 paratype queens, 15 paratype males eclosed in laboratory, xi.1987 and viii-ix.1988 (X. Espadaler), 1 paratype worker with same data as holotype but 7.vi.1992 (X. Espadaler). Paratype-depositories: MCZC, MNHN. NHMW, XEPC.