About Monomorium ergatogyna Wheeler, 1904
Monomorium ergatogyna is a species of myrmicine ant. This ant is shiny black, has only a single worker caste, making it a monomorphic species. It is also polygynous, which means a single colony contains multiple fertile queens living together. This species is native to California, Nevada, and Utah. It is usually found in cities or on the coast; in California, it also occurs on islands near the coast. Compared to other species in the Monomorium genus, M. ergatogyna has the longest-lived queens, which can survive up to 2 years in captivity. M. ergatogyna is often mistaken for Monomorium carbonarium because the two species look very similar. Argentine ants (Linepithema humile) have been observed actively displacing this species from its original native territory. There has been speculation about differences between the island and coastal mainland populations of this species in California. Some researchers argue that mainland populations are not actually "true" M. ergatogyna, but instead a separate species or subspecies; they cite size differences between island queens and mainland queens to support this claim. Another observation notes that mainland populations appear to be allopatric, but more evidence is required to confirm this claim.
