Identification key of Disparalona species in South America

1. Labrum without keel ................................................................. D. (M.) leptorhyncha (Daday, 1905)

– Labral keel poorly developed ........................................................................................................... 2

2. Labrum with distal portion relatively elongated, triangular-shaped ..... D. (M.) hamata (Birge, 1879)

– Labrum with distal portion short and rounded .....................................................................................3

3. Postanal margin of postabdomen with three merged marginal denticles and six groups of thin spines, proximal basal spine about four times shorter than distal one ................. D. (M.) tenuispina sp. nov.

– Postanal margin of postabdomen with 10 merged marginal denticles, proximal basal spine about 3.2 times shorter than distal one ....................................................................... D. (M.) lucianae sp. nov.