Key to species of Oxyallagma

Reference to the illustrations of O. dissidens in Garrison et al. (2010) is important in order to accurately identify these species.

1. Females............................................................................................ 2

1’. Males............................................................................................. 3

2 (1). S2 – 6 with middorsal black stripe, S9 with light blue middorsal stripe (Fig. 4 c); cercus ivory white; middorsum of posterior lobe of pronotum strongly bent dorsally (Northern Peru, Ecuador, and Southern Colombia).................. O. dissidens

2’. No middorsal black stripe on S2 – 6, nor light blue middorsal stripe on S9 (Figs. 5 b, d); cercus dark brown; middorsum of pos- terior lobe of pronotum only slightly bent dorsally (Fig. 6 a) (Northern Colombia)...................... O. colombianum

3 (1’). Genital ligula without small latero-medial pointed lobes; paraproct with swollen semicircular ventral branch as wide as cercus; cercus with two short ventroapical processes (Northern Peru, Ecuador, and Southern Colombia).............. O. dissidens

3’. Genital ligula with small latero-medial pointed lobes (Fig. 6 b); paraproct with ventral branch not swollen, narrower than half of cercus (Figs. 6 c – d); cercus with one ventroapical process (Fig. 6 d) (Northern Colombia).............. O. colombianum