Cymothoid isopods parasitic on fishes: current knowledge and future perspectives
Cymothoid isopods (Crustacea: Peracarida) are large ectoparasites of fishes. Mature females and males inhabit the buccal or branchial cavities, or burrow into the abdomen, or attach to the body surface of marine, brackish, and freshwater fishes. The mancae, which are released from the brood pouch of adult females, spend a planktonic period and develop into early juveniles infecting host fishes. Currently, 399 species in 49 genera of the family Cymothoidae have been recorded worldwide, including 46 species known from Japan and its adjacent waters. This paper provides a comprehensive review of cymothoid taxonomy, morphology, parasitology, molecular characteristics (cytochrome
The costs and benefits associated with
reproduction differ between males and females,
potentially leading to sex-specific movement patterns
during spawning. In Hiroshima Bay, black sea bream
Acanthopagrus schlegelii predominantly spawns
in oyster farming areas (OFAs), where feeding and
spawning sites spatially overlap. Because this species
is likely an income breeder, males and females are
expected to differ in their movement patterns within
OFAs, reflecting sex-specific reproductive tradeoffs during the spawning season. To examine this
expectation, we used ultrasonic biotelemetry to track
reproductively active individuals and analyse their
horizontal and vertical movements. Males showed
broader space use and more frequent vertical movements, especially in the evening, whereas females
tended to stay near particular rafts with more localised movement and lower vertical activity. These
sex-related differences in horizontal and vertical
movement suggest more active mate...Patrolling males and waiting females: sex-specific reproductive movement patterns of black sea bream in oyster farming areas
