Key to the known males of the genus Longior

1a. Cuticular swelling present next to the head...................................................... L. surieli n. sp.

1b. Cuticular swelling not present next to the head.............................................................. 2

2a. Demanian indexes a>20 and c<40.............................................................. L. longicollis

2b. Demanian indexes a<20 and c>40........................................................................ 3

3a. Tail tip with a hammer-like appearance due to a ventral bending and a dorsal knob-like protuberance.... L. zumpimito n. sp.

3b. Tail tip without a hammer-like appearance due to a ventral bending and a dorsal knob-like protuberance................ 4

4a. Nerve ring encircling procorpus at ca. 35% of its length................................................ L. longior

4b. Nerve ring encircling procorpus at ca. 40%–45% of its length.................................................. 5

5a. Excretory pore located at ca. half of the body-width posterior to the basal bulb....................... L. lamothei n. sp.

5b. Excretory pore located at ca. one body-width posterior to the basal bulb................................... L. similis