Merlinius macrodens
(Allen, 1955) Siddiqi, 1970
Syn.: Tylenchorhynchus macrodens Allen, 1955
Nagelus macrodens (Allen, 1955) Siddiqi, 1979
Photo Gallery- holotype

Dimensions.  4 Females  L = 1.02 - 1.12 mm  a = 30 - 32  b = 5.1 - 6.0  c = 14 - 15  V = 50 - 55  Stylet 43 - 48 u long
                    6 Males  L = 0.87 - 1 10 mm  a = 31 - 39  b = 4.8 - 5.6  c = 10 - 12  T = 46 - 49 per cent  Stylet 41 - 48 u long
Female (holotype).  L = 1.09 mm  a = 30  b = 5.1  c = 14  V = 55
Body cylindrical, tapering at both ends.  Lip region bluntly rounded, set off from body contour by constriction, bearing 7 annules.  Labial sclerotization heavy, conspicuous.  Stylet 48 u long, robust, with large rounded knobs.  Deirids easily seen.  Excretory pore opens at level of base of isthmus.  Esophageal-intestinal valve hemispherical.  Ovaries outstrectched.  Spermatheca containing spermatozoa present.  Tail subcylindrical, with terminus bluntly rounded, not striated.  Lateral field with 6 incisures.  Phasmids prominent, opening slightly anterior to middle of tail.
Male (allotype).  L = 1.05 mm  a = 36  b = 5.4  c = 12  T = 46 per cent Stylet 48 u long.
Similar to female.  Bursa envelops tail.  Spicules tylenchoid.  Gubernaculum simple, curved trough.
Type host.  Soil at roots of brush.
Type locality.  Mount Olympus, Utah.

Tylenchorhynchus macrodens is characterized by the set-off lip region and the conspicuous labial sclerotization.  This species is similar to grandis, from which it differs in having a longer stylet- 48 u compared to 29 u for grandisT. macrodens is known only from the type locality.
(Description- Allen, 1955)