Revisionary Notes on the Sanguinea and Neogagates Groups of the Ant Genus. Formica

In recent years, specialists engaged in ecological and regional studies of North American ants have repeatedly .calledupon us to check species identification against types and other "historic" material in the Museum of Compar- ative Zoology (MCZ).The specialist working away from such a collection is likely to assume that the difficulty can readily be cleared up by mere comparison of his fresh material against the Museum series; unfortunately, such comparison by itself rarely produces satisfactory results.Of the groups arriving at the MCZ, one causing repeated difficulty is the so-called subgenus Raptiformica of Formica.In many ways, it exemplifies the current taxonomic conditions within many of our commonest groups of ants.The principal fault .of the accepted Raptifomica ar- rangement lies in an excessive unrecognized synonymy, which in turn stems from pa.st failure to appreciate the extent of allometric and other normal expressions of intra- specific variation.Species such as pergandei and rubicunda have been founded in large part on supposed differences in head shape, but closer examination shows these and .othercases to be nothing more than size variants along the sme general allometric gradient.Trivial variations in pilosity, sculpturing, and ,color have also been much overworked in separating "species"; examination of enough material soon reveals most such variation as con- tinuously intergradient and broadly bridging the old gaps.Another situation bound to give continuing trouble in the future concerns he elusiveness of presumed sibling species such as F. parcipappa, F. curiosa and F. wheeleri