Pseudobiceros bedfordi

Pseudobiceros bedfordi (common names Persian carpet flatworm^[1] and Bedford's flatworm) is a species of flatworm in the family Pseudocerotidae.^[2]

Pseudobiceros bedfordi
Scientific classification
Kingdom:	Animalia
Phylum:	Platyhelminthes
Order:	Polycladida
Family:	Pseudocerotidae
Genus:	Pseudobiceros
Species:	P. bedfordi
Binomial name
Pseudobiceros bedfordi (Laidlaw, 1903)
Synonyms
Pseudoceros bedfordi Laidlaw, 1903

This species has two penises, which it uses to engage in penis fencing, attempting to inject sperm into its opponent in order to fertilize it, while simultaneously avoiding being fertilized by their opponent.^[3]

Description

Pseudobiceros bedfordi is a large polyclad flatworm approximately 8–10 cm in length. It has a distinctive pattern consisting of a brown to black background, with multiple transverse, bilateral pink lines around thousands of tightly spaced, bright yellow spots,^[4] pink undulating spots with stripes on the sides of the body.^[5]

The edges of the body are usually ruffled. The underside of Pseudobiceros bedfordi is pale pink. The front of the body has a pair of erect pseudotentacles.^[1]

Distribution

This species is found in Indonesia, Malaysia, Kenya, Micronesia, Northern Mariana Islands, Thailand, Australia, Philippines, Solomon Islands, Myanmar, and Palau.^[6]

Habitat

Pseudobiceros bedfordi is found on coral rubble^[4] and ledges in back reefs, coastal bays, and in lagoons.^[5]

Behaviour

This worm is fast-moving, and is able to swim by undulating its body.^[4]

Diet

Pseudobiceros bedfordi feeds on ascidians and on crustaceans that are small enough to swallow.^[5]

Reproduction

Two specimens of Pseudobiceros bedfordi about to engage in penis fencing

Like all flatworms in the genus Pseudobiceros, they are hermaphroditic and have two penises. During mating, they fence with one another, using their penises, attempting to stab and inject sperm in their opponent, while avoiding being fertilized by their opponent. They are able to inseminate their opponent by injecting their sperm into any region of the other's body they are able to penetrate. After successfully injecting the other, the spermatozoa stream through their partner's body on their way to ovaries, where they will fertilize the eggs. The stream is visible through the body tissue of the worm, appearing as pale streaks, like lightning jags.^[7][8]