Parasitic Copepods of Mackerel - and Tuna-like Fishes (Scombridae ...

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spinules at articulation with basipod; basipod with a
cluster of long spinules arranged in a circle near inner
margin and a long, stout seta at outer distal corner;
exopod first segment with a patch of long spinules
along outer margin and a heavy serrated spine at
outer distal corner, second segment with serrated spine
at outer distal corner and an inner seta, third segment
with 3 serrated spines, a fringed terminal spine,
and 5 terminal to inner setae (last 5 spines armed on
1 margin only) ; endopod first 2 segments each with
a row of spinules on distal margin in addition to usual
inner setae, last segment with 2 short, outer, lightly
fringed spines and 3 terminal setae. Leg 3 (Figure
336) coxopod with a row of stout spinules at outer
distal corner; basipod with 3 patches of spinules (outer
2 fine, inner patch heavier) and a seta on outer distal
corner; exopod similar to leg 2 except no spinules on
first segment and 1 less spine on last segment; endopod
as in leg 2 except 1 less seta on last segment. Leg 4
(Figure 33c) as in leg 3 except 1 less patch of fine
spinules on basipod; 1 less spine and seta on exopod
last segment; endopod patches of spinules larger,
setae with short spinules rather than usual plumosities,
last segment with only 1 long seta. Leg 5 (Figure 33d)
with 2 prominent patches of spinules in distal third,
innermost with longer spinules; 1 lateral, naked seta
and 3 terminal setae, outer 2 finely spinulose (all setae
of about equal length).
MALE.—We did not collect males of this species
but Pillai noted (1965:53) that the second segment
of the maxilliped bears 2 rows of "tubercles" on inner
margin.
REMARKS.—This species has been collected only
from species of Rastrelliger from the Indo-West
Pacific.
Orbitacolax Shen, 1957
Orbitacolax aculeatus (Pillai, 1962),
new combination
FIGURES 34, 35a-b, 100
Bomolochus aculeatus Pillai, 1962a: 610.
MATERIAL EXAMINED.—2 collections containing
15 9 from the nasal sinuses of 2 Rastrelliger faughni
from Manila and Lingayan Gulf, Philippines.
FEMALE.—Body form as in Figure 34a. Total length
1.71 mm. Greatest width 0.73 mm. Rostrum protrud-
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
ing from between bases of first antennae and bearing
a pair of ventral hooks (see Figure 346).
Abdomen 3-segmented, ventral surface covered with
spinules. Caudal rami about twice as long as wide,
each with one lateral, 2 subterminal, and 3 terminal
setae (innermost much stouter and longer than
others). First antenna (Figure 346) bearing 15
plumose and 6 naked setae along outer edge and 1
plumose and 3 naked setae directed posteriorly on
first 3 segments, fourth and fifth segments with 3 setae
each, last segment with 7 short and 1 long terminal
setae. Second antenna (Figure 34c) with 6 rows of
small hooks along outer edge of second segment and
6 setae at tip (Pillai indicates 5). Labrum with 2
dense patches of spatulate spinules, posterior corners
produced as spinulose knobs. Other oral appendages
as in Figure 34d. Maxilliped (Figure 34e) hook with
accessory process, posterior edge of basal segment with
spinules (not indicated by Pillai).
We will not repeat a full description of legs 1-5 but
rather restrict our discussion to those points where our
material differs with the description of Pillai's. Pillai
illustrated the basipod of leg 1 with 1 large patch of
spinules; in our specimens there are 2 (see Figure 34/).
Leg 2 as described by Pillai except endopod second
segment with 2 setae rather than one. Leg 3 exopod
similar to that of leg 2; endopod first and second segments
each with one inner seta, third segment with 2
naked subequal outer spines and 2 inner setae. Pillai
shows no setae on first and second segments and only
one outer spine on third segment. Legs 4 and 5 (Figure
35a,6) as described by Pillai.
REMARKS.—In spite of the differences between our
material and the description given by Pillai we feel
certain that we are dealing with the same species as
the same genus of host is involved in both cases. So
far this copepod has been collected only from Rastrelliger
from India and the Philippines.
Pumiliopes Shen, 1957
Pumiliopes capitulatus Cressey and Boyle, 1973
FIGURES 35c-e, 36, 37, 100, 126a-c
Pumiliopes capitulatus Cressey and Boyle, 1973:1.
MATERIAL EXAMINED.—23 collections containing
35 5 from the orbits of the following hosts and localities:
Rastrelliger kanagurta the Red Sea, Sri Lanka,