Key to US Myrmecina species

Key to United States species of Myrmecina based on workers, modified from Deyrup (2015) and MacGown (2023).

1

 * Head, mesosoma, and waist shiny, with reduced parallel carinae, interrugal rugoreticulation lacking; propodeal spine blunt, pre-propodeal spine lacking (Fig. 2A) Myrmecina davisoni
 * Head, mesosoma, and waist with strong sculpture, conspicuous parallel carinae present with rugoreticulation in between carinae; propodeal spine acute, small triangular pre-propodeal spine present (Fig. 2B)

2

 * Total length 2 mm or less; postpetiole with a distinct ventral process that is directed anteriorly (Fig. 3A); color dark reddish brown Myrmecina cooperi


 * Total length greater than 2.0 mm; postpetiole concave below, lacking a conspicuous process (Fig. 3B); color reddish brown to blackish brown Myrmecina americana