Harris: Male antennule of porcellidiid copepods 
153 
Figure 28. Acutiramus cumulus sp. nov. male: (A) anterior cephalosome (ventral, showing rostrum); (C) P5; (E) left caudal ramus. 
Acutiramus iwasakii sp. nov. male: (B) left caudal ramus; (D) P5; (F) antennule denticles; (G) antennule setae (7t series not shown). Scale 
bar: A = 0.2 mm. B - 0.04 mm. C, D, G = 0.065 mm. E, F = 0.04 mm. 
length of antennule. (No fully extended antennule available 
for measurement and study of denticles). Structure and 
setation of mouthparts and ambulatory limbs as for female. 
P2 has two terminal setae on segment 3 of the endopod, P5 
is trapezoidal with apical angle 47° (Fig. 28C) no rows of 
setules at base of terminal setae. 
Remarks. The trivial name refers to the way in which terminal 
setae T2, T3 and T4 on the female caudal ramus are heaped 
together at the apex (L. cumulus = a heap or pile), this feature 
has not been found on any other member of the family. 
Specimens of A. cumulus and A. iwasakii were found 
living together in the same shells inhabited by hermit crabs. 
