QUADRIACANTHUS SPP. (MONOGENEA, DACTYLOGYRIDEA) FROM HETEROBRANCHUS LONGIFILIS (TELEOSTEI, CLARIIDAE) IN THE RIVER BOUMBA (CONGO BASIN: CAMEROON) WITH THE DESCRIPTION OF THREE NEW SPECIES. Vie et Milieu, 67(2) 2017: 81-89. 86 [Zoological Record Volume 154]