10. Mastigusa arietina

– found under the stone in the colony of Camponotus ligniperdus (Latreille, 1802) . A rare species of warmer grasslands and xerothermic habitats, living in or near ant colonies; nevertheless, its relationship with ants is not clear (the same concerns all myrmecophilous spiders). Referred nding is remarkable because the occurrence in association of this ant species has not hitherto been published.The following records from Slovakia are available:

NR Rohy near the town of Detva (48°32̍ 53.27̍̍N; 19°21̍11.58̍̍ E, 577 m), in an under-stone colony of Lasius niger, March 3, 1991, 1 ♂; Krupinská planina plateau – Plášťovce (48°10̍15.63̍̍N; 19°0̍24.78̍̍E, 279 m), May 23, 1995, 1 ♀ in the colony of Messor structor on a xerothermic slope, April 1, 1994, 2 ♀ – together with the very rare leiodid-beetle Attaephilus arenarius (Hampe, 1852) ! (Franc, 1999); Krupinská planina plateau – Rykynčice (48°12̍ 21.70̍̍N; 18°57̍ 40.40̍̍E, 267 m, the same circumstances, April 9, 1994, 2 ♂, 1 ♀, all records V. Franc and A. Hanzelová lgt.; Ostrôžky Mts – Nedelište (48°23̍30.62̍̍N; 19°25̍ 8.63̍̍E, 457 m), in the colony of Lasius alienus in a xerothermic oak forest, April 22, 2000, 1♂ V.Franc lgt. (all records Franc, 2007); NR Zoborská lesostep near the town of Nitra (DFS 7674), April 29, 1978 (Gajdoš, Krumpál, 1987); National Park Poloniny – Ruské (49°07̍7.37̍̍N; 22°19̍51.91̍̍E, 568 m), semi-xerothermic pasture, pitfall trap, 1 specimen undated (Žila, Gajdoš, 2014); Ostrôžky Mts – Praha (48°22̍ 07.69̍̍ N; 19°30̍26.27̍̍E, 504 m), xerothermic shrubby pasture, in the colony of Messor structor, 3 ♀ (Franc, 2010b).

Its abundance is recently probably increasing due to the global warming.