Taxonomic Study of Genus Formica L.from Northwest China with Descriptions of Nine New Species and Four New Records (Hymenoptera:Formicidae:Formicinae)

A key to 26 species of the ant genus Formica collected from Northwest China and 71 figures for workers of each species were provided,and nine new species and four new records were described in the present paper. 1 Formica miniocca sp.nov.Chang et He (Figs.2,3,47) This species is similar to F.sanguinea Latreiile,but the former alitrunk,legs and petiole node bright red;head dark red,area between frontal carinae and eyes brown;eyes smaller and much longer,maximum diameter 0.43-0.50 mm;pubescence on head and alitrunk short and sparse. Holotype worker,No.98-604,9-Ⅷ-1998,Pengyang,1 700 m,Ningxia Hui Autonomous Region,coll.CHANG You-de.Paratypes 3 workers,No.98-515,same colony as holotype. 2 Formica liopthalma sp.nov.Chang et He (Figs.13,14,51) This species is similar to F.longicepis Dlussky,but the former pubescence on both eye faces lacking;1/3 up part of petiole node bent forward;behind half part of head dorsum black;hairs very sparse. Holotype worker,No.99-096,18-Ⅴ-1999,Wuwei,3 400 m,Gansu Province,coll.CHANG You-de.Paratypes 7 workers,No.99-254;12 workers,No.99-005;4 workers,No.99-090,same as holotype. 3 Formica robusta sp.nov.Chang et He (Figs.18,19,54) This species is similar to F.candida F.Smith,but the former head back,alitrunk and legs,petiole node,gaster,antenna and scape reddish brown;body stout,pronotum width 0.75-0.86 mm;eyes larger,maximum diameter 0.37-0.41 mm. Holotype worker,No.98-109,8-Ⅸ-1998,Liupan Mountains,1 900 m,Jingyuan,Ningxia Hui Autonomous Region,coll.CHANG You-de.Paratypes 4 workers,No.99-606,same as holotype;2 workers,No.98-423,3-Ⅹ-1998;12 workers,No.98-099,2-Ⅹ-1998;7 workers,No.98-123,3-Ⅹ-1998;Longde,1 900 m,Ningxia Hui Autonomous Region,coll.CHANG You-de. 4 Formica dachaidanensis sp.nov.Chang et He (Figs.22,60) This species is similar to F.candida F.Smith,but the former hairs on posterior margin of 1-2 or 1-3 gastral tergites and pubescence on gaster lacking;mandibles,antenna scape and legs reddish brown. Holotype worker,No.99-207,15-Ⅵ-1999,Dachaidan,3 020 m,Qinghai Province,coll.CHANG You-de.Paratype 1 worker,No.99-248,same as holotype. 5 Formica liogaster sp.nov.Chang et He (Figs.11,12,59) This species is similar to F.candida F.Smith,but the former 1-3 gastral tergites with no hair and pubescence;mesonotum straight in profile,superior border significantly higher than pronotum. Holotype worker,No.99-152,22-Ⅵ-1999,Haiyuan,1 720 m,Ningxia Hui Autonomous Region,coll.CHANG You-de.Paratypes 8 workers,No.99-196,same as holotype. 6 Formica breviscapa sp.nov.Chang et He (Figs.23,24,63) This species is similar to F.japonica Motschulsky,but the former alitrunk declivity steep;epinotum in profile with 100-105 angle between the base and declivity;antennal scape shot,index of scape length with head length 81-106;alitrunk with several short and blunt erect hairs. Holotype worker,No.98-009,6-Ⅵ-1998,Helan Mountains,2 280 m,Ningxia Hui Autonomous Region,coll.CHANG You-de.Paratypes 3 workers,No.98-039,same as holotype;14 workers,No.98-077,2-Ⅹ-1998,Longde,1 900 m,Ningxia Hui Autonomous Region,coll.CHANG You-de. 7 Formica aseta sp.nov.Chang et He (Figs.20,21,62) This species is similar to F.japonica Motschulsky,but the former hairs on gaster very sparse and hairs on posterior margin of gastral tergites lacking;antennal scape short,index of scape length with head length 106-119;alitrunk petiole node reddish brown,gaster brown,but slightly reddish. Holotype worker,No.98-607,9-Ⅷ-1998,Pengyang,1 700 m,Ningxia Hui Autonomous Region,coll.CHANG You-de.Paratypes 4 workers,No.98-054,same as holotype;10 workers,No.98-338,27-Ⅷ-1998,Jishishan,2 100 m,Gansu Province,Coll.CHANG You-de. 8 Formica villiscapa sp.nov.Chang et He (Figs.27,28,65) This species is similar to F.pratensis Retzius,but the former whole body including antennal scape and first segment of funculus with dense acute short erect hairs. Holotype worker,No.99-100,20-Ⅵ-1999,Hezuo,3 100 m,Gansu Province,coll.CHANG You-de.Paratypes 4 workers,No.98-184;11 workers,No.99-103;5 workers,No.99-210,same as holoptype. 9 Formica delinghaensis sp.nov.Chang et He (Figs.31,32,55) This species is similar to F.wongi Wu,but the former antennal scapa short,index of scape length with head length 89-100;body bright. Holotype worker,No.99-252,15-Ⅵ-1999,Delingha,2 750 m,Qinghai Province,coll.CHANG You-de.Paratype 1 worker,No.99-221,same as holoptype.