Question

Claspers of male Scoliodon develop in relation to
(a)Pectoral Fins
(b)Pelvic fins
(c)Anal or ventral fin
(d)Dorsal Fins

Answer 1

Hint: Claspers are external copulatory appendages. They are deeply grooved cartilaginous extensions that are found in pairs. They are associated with the fins, located on the bottom of the fish which have the main function to help balance the fish and keep it level.

Complete answer:
Scoliodon or Dogfish belongs to the shark family. Unlike most other fishes which release sperms and eggs into the water and fertilize externally, sharks demonstrate internal fertilization. In order to deliver sperms to the females, male sharks bear elongated external copulatory appendages known as Claspers. They are analogous to the penis in higher animals.
They are a pair of hard and deeply grooved cartilaginous extensions of the pelvic fins of these organisms.

Additional Information:
 -Unlike most other fishes, sharks do not demonstrate external fertilization.
-They deliver the sperms directly into the female body and thus internal fertilization is seen in them.
-This has a disadvantage in the sense of the number of eggs that are fertilized at one time is less and hence the number of offspring produced is less.
-Conversely, since they are nourished inside the female bodies and not released into the water as eggs, parental care is seen for a longer time and long term survival is better.
-The sperms from the cloaca of the sharks pass into the claspers and then transferred to the female. Each clasper shows a closed groove with an anterior opening, apopyle which lies near the cloaca and a hypostyle which is a posterior opening.
-Sperms enter the apopyle and then transfer to the cloaca of the female during coitus.
-This whole apparatus is developed in relation to the Pelvic fins.

So, the answer is, ‘Pelvic fins.’

Note:
 -There is another accessory organ called the siphon or siphon tubes which help the sharks in delivering the sperms into the female cloaca.
-Claspers are not unique to the sharks and are also found in rays and skates too.