314
MARINE MOLLUSCS AS HOSTS FOR SYMBIOSES
third and fourth pairs of legs similar except for certain differences in
armature, stronger inner basipodite spine absent and outer basipodite
spine slender in all three legs ; leg spine and setal formula as follows :
Lag 1
Leg 2
Leg 3
Lag 4
exp and
exp and
exp end
exp end
1st podomere
1:0 0:l
1:l 0 : l
1:l 0 : l
1 : l 0:l
2ndpodomere
1:l 0:l
1:l
0:2
1:l 0:2
1 : l 0:2
3rd podomere
6
2
7
5
8
6
8
5
fifth leg with three slender setae on inner expansion of basal podomere,
middle seta 0.115 mm long, two shorter setae subequal, about 0.048 mm
long; single seta, 0.044 mm, a t outer corner of podomere; distal
podomere 3.1 times longer than wide, averaging 0.097 mm x 0.031 mm,
with four terminal setae, three subequal in length (0.046-0*051 mm),
fourth member of quartette, next to innermost, longer (0.067 mm),
fifth seta, 0.073 mm long, on outer edge of podomere at junction of
distal two quarters, with small spines along both edges of podomere ;
sixth pair of legs visible on anteroventral part of genital segment,
represented by three setae on either side of oviducal opening.
Adult male (Fig. 211) resembles female in color and body form;
total length 0.705-0-800 mm (average 0-781 mm), greatest body width
0.328 mm, a t level of first thoracic segment ; abdomen of four segments ;
rostrum 0.025 mm long ; head plus somite of first leg 0-223 mm long,
second, third, fourth, fifth and sixth legs measure 0.070, 0.083, 0.064
0.057 and 0.061 mm long respectively ; caudal ramus, 0-020 mmlong, like
that of female ; first antenna subprehensile, with nine segments measuring 0.030, 0.048, 0.023, 0.006, 0.029, 0.009, 0.021, 0.022 and 0.032 mm
respectively, aesthetask on fifth segment measures 0.109 mm long ;
second antenna similar to that of female ; second through fourth legs
like those of female ; distal podomere of fifth leg, 0.042 mm x 0.018 mm,
shorter than that of female, with few minute spines on slightly convex
broad outer surface, with middle spine, 0.043 mm long, broad and with
fine hair-like tip; inner expansion of proximal podomere less pronounced than in female, with two setae, one long (0.057 mm) and one
short (0.017 mm); sixth leg as broad lobe bearing spinose, distally
naked setae, a row of small spines near bases of two inner setae ; spermatophore, 0.070 mm x 0.030 mm with slender neck.
MARINE MOLLUSCS AS HOSTS FOR SYMBIOSES
third and fourth pairs of legs similar except for certain differences in
armature, stronger inner basipodite spine absent and outer basipodite
spine slender in all three legs ; leg spine and setal formula as follows :
Lag 1
Leg 2
Leg 3
Lag 4
exp and
exp and
exp end
exp end
1st podomere
1:0 0:l
1:l 0 : l
1:l 0 : l
1 : l 0:l
2ndpodomere
1:l 0:l
1:l
0:2
1:l 0:2
1 : l 0:2
3rd podomere
6
2
7
5
8
6
8
5
fifth leg with three slender setae on inner expansion of basal podomere,
middle seta 0.115 mm long, two shorter setae subequal, about 0.048 mm
long; single seta, 0.044 mm, a t outer corner of podomere; distal
podomere 3.1 times longer than wide, averaging 0.097 mm x 0.031 mm,
with four terminal setae, three subequal in length (0.046-0*051 mm),
fourth member of quartette, next to innermost, longer (0.067 mm),
fifth seta, 0.073 mm long, on outer edge of podomere at junction of
distal two quarters, with small spines along both edges of podomere ;
sixth pair of legs visible on anteroventral part of genital segment,
represented by three setae on either side of oviducal opening.
Adult male (Fig. 211) resembles female in color and body form;
total length 0.705-0-800 mm (average 0-781 mm), greatest body width
0.328 mm, a t level of first thoracic segment ; abdomen of four segments ;
rostrum 0.025 mm long ; head plus somite of first leg 0-223 mm long,
second, third, fourth, fifth and sixth legs measure 0.070, 0.083, 0.064
0.057 and 0.061 mm long respectively ; caudal ramus, 0-020 mmlong, like
that of female ; first antenna subprehensile, with nine segments measuring 0.030, 0.048, 0.023, 0.006, 0.029, 0.009, 0.021, 0.022 and 0.032 mm
respectively, aesthetask on fifth segment measures 0.109 mm long ;
second antenna similar to that of female ; second through fourth legs
like those of female ; distal podomere of fifth leg, 0.042 mm x 0.018 mm,
shorter than that of female, with few minute spines on slightly convex
broad outer surface, with middle spine, 0.043 mm long, broad and with
fine hair-like tip; inner expansion of proximal podomere less pronounced than in female, with two setae, one long (0.057 mm) and one
short (0.017 mm); sixth leg as broad lobe bearing spinose, distally
naked setae, a row of small spines near bases of two inner setae ; spermatophore, 0.070 mm x 0.030 mm with slender neck.