Key to the species of Hughjonestrongylus

1a Synlophe with more than 25 ridges at the mid body.......................................................... 2

1b Synlophe with less than 25 ridges at the midbody........................................................... 5

2a Spicule tips complex.................................................................................. 3

2b Spicule tips simple.................................................................................... 4

3a Spicules 330–460 long, 12.1 % body length. Female tail twisted dorsally, infundibulum longest element of ovejector.................................................................................................. H. ennisae

3b Spicules 450–700 long, 12.6% body length. Female tail curved ventrally, infundibulum and vestibule shortest elements of ovejector...................................................................................... H. implex us

4a Synlophe with 27–30 ridges at mid body. Spicules 310–350 long. Female posterior end not expanded, tail may be obscured by large cement plug, 4 eggs in utero........................................................ H. pervulgatus n. sp.

4b Synlophe with 25–27 ridges at midbody. Spicules 290–390 long. Female posterior end expanded, 10 eggs in utero................................................................................................... H. woolleyae

5a Synlophe with 18 ridges at mid body, ridges 1’, 2’ forming a comarete. Spicules 390 long, right tip curved left tip hooked...................................................................................... H. vanimoensis n. sp.

5b Synlophe with 20–24 ridges at midbody without comarete. Spicule tips similar.................................... 6

6a Synlophe with 22–23 ridges at mid body. Spicules 145–230 long, 13.6 % body length, gubernaculum 17–24. Female tail reflected ventrally, infundibulum longest element of ovejector, 2– 4 eggs in utero................... H. wanumaensis n. sp.

6b Spicules longer than 230, gubernaculum longer than 25, infundibulum not longest element of ovejector, more than 4 eggs in utero............................................................................................... 7

7a Synlophe with 21–24 ridges mid body. Spicules 250–320, 9.8 % body length, gubernaculum 27 long. Female tail twisted and flexed ventrally, sphincter longest element of ovejector................................................. H. mirzai

7b Spicule mean length> 285,> 10.5 % body length. Female tail not twisted, elements of ovejector similar lengths.......... 8

8a Synlophe with 20–24 ridges, at mid body. Spicules 280–365 long, 14.5% body length, gubernaculum 27–29 long, spicule tips curved. Female posterior end expanded, 8 eggs in utero ............................................ H. amplicauda

8b Synlophe with 19–23 ridges at mid body. Spicules 230–385 long 11.5% body length, gubernaculum 29–35 long, spicule tips straight. Female posterior end not expanded, tail with spike, 13 eggs in utero......................... H. singawauensis