Key to group 4 female Heth spp.

1. Body with numerous somatic spines from cervical collar to at least the isthmus.................................... 2

- Body without prominent somatic spines except for four pairs of lateral spines; posterior three pairs with broad bases; lateral alae present from posterior esophagus to anus (Fig. 15C); females 1,332 –1,731 µm long....................... H. lamothei

2. Body with 5–7 lateral spines from cervical collar to isthmus; with multi-cusped sensory papillae posterior to cervical collar (Fig. 15D).................................................................................... H. poeyi

- Body with six lateral-sublateral rows of spines from cervical collar to anus........................................ 3

3. Anterior region laterally with a long row of large, multicusped papillae, the first two of which are doubled; somatic spines smooth or lightly serrated (Fig. 15A); female length 1,562 –1,702 µm .................................... H. adolphi

- With four pairs of bifurcated lateral spines; spines of sublateral rows heavily serrated in esophageal region (Fig. 15B); female length 1,983 –2,308 µm ..................................................................... H. josephinae