Heth Cobb 1898
Creators: name: Phillips, Gary
name: Moulton, John K.
name: Bernard, Ernest C.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Nematoda
Secernentea
Oxyurida
Thelastomatidae
Heth

description: Key to group 2 Heth spp.
1. Multiple cuticular knob–like papillae in anterior esophageal region............................................. 2
- Knob-like papillae absent near head region, rarely one or two close to the cervical collar............................ 9
2. Lateral cervical collar spines reaching or overlapping proximal base of anterior lateral spines........................ 3
- Lateral cervical collar spines not reaching anterior lateral spines................................................ 6
3. Anterior and posterior lateral spines about equal in length..................................................... 4
- Posterior lateral spines much longer than anterior spines (Fig. 11G); anterior anal lip normal, without large lobe; female 2,340 – 3,230 μm long............................................................................... H. initiensis
4. Anterior anal lip with large lobe extending over anus; female 2,610 –4,225 μm long (Fig. 11E)............ H. impalutiensis
- Anterior anal lip not swollen into large lobe................................................................ 5
5. Shield length and width about equal (Fig. 11M); female 1,365 –2,075 μm long.......................... H. taynguyeni
- Shield longer than wide (Fig. 12C); females 2,550 –2,640 μm long................................. H. vietnamensis
6. Shield width twice that of its length; female 2,190 –4,483 µm long (Figs. 2A, B, D, 6A)................. H. pivari n. sp.
- Shield length and width about equal, or length much longer than width.......................................... 7
7. Shield tapering, up to 3 times longer than wide (Fig. 12A); females 2,180 –2,370 μm long................ H. tonkinensis
- Shield width and length similar, rounded or trapezoidal in shape................................................ 8
8. Shield rounded or ovoid; lateral spines less than 20 µm long (Fig. 11A); female 1,105 –1,440 μm long.......... H. baudini
- Shield trapezoidal; lateral spines 28–30 μm long (Fig. 11L); female 1,905 –2,575 μm long.................... H. taybaci
9. Cervical collar overlapping proximal base of anterior lateral spines............................................ 10
- Lateral cervical spines not overlapping anterior lateral spines................................................. 12
10. Eight longitudinal ridges extending from base of posterior lateral spines to vulva (Fig. 11B); female 2,160 –2,600 μm long.............................................................................................. H. costata
- Longitudinal ridges absent............................................................................ 11
11. Anterior and posterior lateral spine pairs fused, 26–33 μm long; shield a semicircle, about twice as wide as long (Fig. 11I); females 2,700 –3,024 μm long................................................................. H. orthopori
- Anterior lateral spines widely separated, 50 μm long; posterior lateral spines 55 μm long, bases closer but not touching (Fig. 11K); females 2,010 –2,360 μm long........................................................... H. sutherlandi
12. Lappets continuous, not separated laterally................................................................ 13
- Lappets separated................................................................................... 15
13 Length of cervical spines along lappet edges irregular, some spines forked; anterior and posterior lateral spines with fused bases (Fig. 12B); females 1,700 –2,800 μm long........................................................ H. tuxtlensis
- Cervical spines along lappet edges about the same size...................................................... 14
14. Shield forming a W-shape, length and width equal (Fig. 11H)............................................. H. juli
- Shield entire, not bilobed, well anterior to base of anterior lateral spines (Fig. 11C)..................... H. dimorphum
15. Wing-like lateral alae present; each pseudolabial plate with three conspicuous spines; cuticular collar with more than 100 spines; shield tapering, (Figs. 12D); female length 2,400 –2,960 μm................................. H. xaniophora
- Lateral alae absent................................................................................... 16
16. Anterior lateral spines widely separated; shield of typical size (Fig. 11J); females 1,970 –2,630 μm long.. H. ortonwilliamsi
- Anterior lateral spines fused basally; shield trapezoidal, small (Fig. 11F); females 1,764 –1,962 μm long....... H. insularis
description: Published as part of Phillips, Gary, Moulton, John K. & Bernard, Ernest C., 2020, Heth pivari n. sp. (Nematoda: Ransomnematoidea: Hethidae) from the indigenous North American millipede Narceus gordanus (Spirobolida: Spirobolidae), with keys for worldwide Heth spp., pp. 486-514 in Zootaxa 4861 (4) on pages 507-508, DOI: 10.11646/zootaxa.4861.4.2, http://zenodo.org/record/4416659