Strictly speaking, it is called haikai no renga (humorous linked poem) or haikai renga, which diverged from the orthodox renga, being made more playful, so it's a form of group literature as well as a general term for the forms of hokku (the first line of a waka poem) and renku (a linked verse).
正しくは俳諧の連歌あるいは俳諧連歌と呼び、正統の連歌から分岐して、遊戯性を高めた集団文芸であり、発句や連句といった形式の総称である。