Nematode Root Parasite — Linford, et al. 
113 
similar anus has been illustrated for Criconema 
squamosum (Cobb, 1913; Taylor, 1936, pi. 46, 
fig. 11). In lateral view this appears as two 
narrow lip-like projections about 1/m wide that 
extend somewhat backward about 1.5 ^ or one- 
fifth the width of the body at this position. This 
character is best seen when the spicula are 
retracted, although the posterior lip can be 
distinguished when they are protruded. 
OCCURRENCE 
We have collected this little nematode from 
three islands of the Hawaiian group: Oahu, 
Molokai, and Maui. On Oahu it occurs widely 
and abundantly in pineapple fields in several 
districts but not in all of the fields where pine- 
apples have long been grown. On Molokai it 
has been taken from a single pineapple field 
location among 16 sampled. On Maui it has not 
been found in a number of pineapple field 
samples, but it was taken from the roots of 
mixed vegetation at elevations of 4,100 and 
6,700 feet above sea level. Other habitats gen- 
erally have not been searched. Limited sampling 
from mixed vegetation and grasslands adjacent 
to heavily infested pineapple fields on Oahu, 
however, has produced few individuals of this 
species, which suggests that the pineapple field 
environment is especially favorable to it. 
Because of its small size and ectoparasitic 
habit this paratylench is readily overlooked. We 
first became aware of its abundance when we 
found large numbers of these parasites attached 
to pineapple rootlets that had been fixed, cleared, 
and stained without washing (Linford, 1942 b: 
97-100). (Fig. 2.) Because their size permits 
most of them to be lost through the finest sieves, 
we adopted the Baermann funnel technique or 
modifications of it for extraction from roots 
and soil. In one comparative test, decanting 
and wet screening recovered 16 paratylenchs per 
gram of soil, all of them adult females, but the 
Fig. 2. Numerous Paratylenchus minutus projecting from a fixed and stained pineapple rootlet. Most, if not 
all, of these nematodes were attached only by the buccal stylet. Crescentic posture is typical of this species when 
relaxed or dead. X 175. 
