What is "heterocongrinae"

The garden eels are the subfamily Heterocongrinae in the conger eel family Congridae. The majority of garden eels live in the Indo-Pacific, but species are also found in warmer parts of the Atlantic Ocean (including the Caribbean) and East Pacific. These small eels live in burrows on the sea floor and get their name from their practice of poking their heads from their burrows while most of their bodies remain hidden. Since they tend to live in groups, the many eel heads "growing" from the sea floor resemble the plants in a garden. They vary greatly in colour depending on the exact species involved. The largest species reaches about in length, but most species do not surpass .