Which type of neuroglia is found outside of the brain?

The glial cells or neuroglia which are a part of the nervous system support neurons by providing appropriate nutrients, insulation, oxygen and elimination of the harmful pathogens. These cells can be found in the regions of brain and spinal cord.

There are several types of glial cells present in brain and spinal cord such as astrocytes, oligodendrocytes, microglia, ependymal cells etc.

The microglia are the neuroglia found in the central nervous system and reside in brain and spinal cord. These neuroglia are found outside the brain providing immunity to the nervous cells by engulfing the foreign particles as the microglia can get transformed into a phagocytic macrophage. These cells also help in repairing the damaged neuronal tissues and participate in extracellular signalling.

the species living around the vents are especially good at dispersal.  

deep-sea vent originates on the floor of the ocean when seawater circulates through hot volcanic rocks, usually situated where the new oceanic crust is being produced.  

biological dispersal refers to the movement of species from their location of birth to their site of breeding, or from breeding site to another. similarly, the oceanic dispersal refers to the movement of the species from one land mass to another by sea crossing.