2l8 UNIVERSITY OF COLORADO STUDIES 



b) Not as above. 



a) Tibiae of posterior legs with simple spur (fig. 2c); spines of meta- 

 thorax short; clypeus flat. 



aa) Maxillary palpi 4-jointed; flagellura without distinct club 

 gradually thickened from base to apex. Aphaenogaster 



bb) Maxillary palpi 5-jointed; flagellum with a distinctly 3-jointed 

 club. Lep to thorax 1 



b) Tibiae of posterior legs with pectinated (toothed) spur (fig. 26); 

 spines of metathorax long; clypeus convex. Myrmica 



Preliminary List of Species of Ants in Northern Colorado 2 



Subfamily: MYRMICINAE 



Aphaenogaster fulva Roger (Boulder). 



Cremastogaster lineolata Say (Boulder). 



Leptothorax acervorum Mayr., var. yankee Emery (Boulder). 



Leptothorax curvispinosus Mayr., subsp. annectens Wheeler (Boulder). 



Leptothorax muscorum Nyl., var. sordidus Wheeler (Boulder). 



Myrmica brevinodis Emery, var. (Boulder, Meeker). 



Myrmica scabrinodis Nyl., var. (Tolland, Boulder). 



Myrmica rubra sulcinodoides Emery (Boulder, Ward). 



Myrmica rubra L., subsp. brevinodis Emery (Boulder, Meeker). 



Myrmica rubra L., subsp. scabrinodis Nyl., var. (Tolland, Boulder). 



Myrmica rubra L., var. sulcinodoides Emery (Boulder, Ward). 



Myrmica mutica Emery. 3 



Pheidole pilifera Roger, subsp. coloradensis Emery (Boulder). 



Pheidole ceres Wheeler (Boulder). 



Pheidole vinelandica Forel (Boulder). 



Pogonomyrmex occidentalis Cresson (Meeker, Boulder, Rifle Gap, New Castle). 



Solenopsis molesta Say (Boulder). 



Sympheidole elecebra Wheeler (Boulder). 



Subfamily: DOLICHODERINAE 



Dorymyrmex pyramicus Roger (New Castle). 



Dorymyrmex pyramicus Roger, var. niger Pergande (Boulder). 



Iridomyrmex analis Andre (Boulder). 



Tapinoma sessile Say (Tolland, Boulder). 



Subfamily: CAMPONOTINAE 



Brachymyrmex heeri Forel, subsp. depilis Emery (Boulder). 



Camponotus levigatus F. Smith (Meeker). 



Camponotus herculeanus L., var. whymperi Forel (Tolland). 



Camponotus maculatus Fabr., subsp. vicinus Mayr., var. nitidiventris Emery (Boulder). 



Formica crinita Wheeler (Boulder). 



Formica jusca L., var. argentata Wheeler (Jenny Lake, Tolland). 



Formica munda Wheeler (Boulder). 



1 This species may be confounded with the workers of Pheidole, or vice versa, their habits are different, 

 however. leptothorax spp. form much smaller colonies often not more than 25 or 50 individuals; also their 

 motion is much more rapid than that of Pheidole spp. The thorax of Pheidole is strongly constricted between 

 the meso- and metathorax; in Leptothorax it is but slightly or not at all constricted. 



* In nearly every case the species listed have been determined by Professor William M. Wheeler, the 

 American authority on Formicidae. 



3 This species has not been found in northern Colorado but according to Professor Wheeler should occur 

 here, since it is so abundant in other localities of Colorado, Idaho and even in British Columbia. 



