What does a newborn baby starfish look like my has little creature that lives on it which looks one-armed complete with suckers.What could be?

Newborn starfish, also known as starfish larvae or echinoplutei, have a distinct appearance that sets them apart from adult starfish. They are typically small, transparent, and have a unique bilateral symmetry, unlike the radial symmetry of adult starfish.

Here's a description of what a newborn starfish might look like:

Body Shape: Newborn starfish have a flattened, oval, or spherical body shape. They may appear delicate and fragile due to their transparent bodies.

Cilia: The entire body of a newborn starfish is covered in tiny, hair-like structures called cilia. These cilia help the larva move freely in the water by generating currents.

Arms: At this stage, starfish larvae do not have the typical arms or rays characteristic of adult starfish. Instead, they have a set of temporary larval arms called brachiolar arms. These arms are covered in adhesive discs or suckers, which help the larvae attach to surfaces.

Feeding Structure: Newborn starfish have a specialized feeding structure called the apical tuft. The apical tuft is located at the front of the larva and consists of a cluster of long cilia. The cilia create water currents that help the larva capture microscopic food particles, such as plankton and algae.

Digestive System: The digestive system of a newborn starfish is relatively simple. It consists of a mouth, a short esophagus, a stomach, and an intestine. The larva absorbs nutrients from the food particles it captures using its apical tuft.

Now, let's discuss the "little creature" that lives on the newborn starfish and looks like a one-armed creature with suckers. It's possible that you're referring to a parasitic organism known as a pycnogonid, also commonly called a sea spider.

Pycnogonids are marine arthropods that are often found attached to various marine organisms, including starfish. They have a unique body plan characterized by a long, slender trunk and a pair of specialized appendages called ovigers, which may resemble a one-armed structure. These ovigers are equipped with tiny claws or hooks that help the pycnogonid grasp onto its host.

Pycnogonids are generally harmless to their hosts and do not typically cause significant harm to the starfish. They attach themselves to the starfish's body to access food particles or debris that may be present on its surface.

If you observe a small, one-armed creature with suckers on your newborn starfish, it's likely a pycnogonid. However, if you're unsure or concerned about the presence of any foreign organisms on your starfish, it's always a good idea to consult with a marine biologist or expert in marine invertebrates for proper identification and guidance.