The late Givetian at Oued Mzerreb has been first investigated by BENSAID (1974) who provided a
  section log of strata which were then assigned to the upper Givetian to basal Upper Devonian
  ("ds I alpha").  With the later definition of the series boundary and according to the proposed level
  for a future Upper Givetian substage (ABOUSSALAM &  BECKER 2002), the whole previously
  studied succession now falls in the Middle Givetian.  BENSAID (1974) mentioned a Manticoceras
  level much higher in the sequence and these true Frasnian beds, including distinctive and important
  global event levels, will be described here for the first time in detail.  The previously documented
  ammonoid taxa from Oued Mzerreb are (with revised taxonomy; identifications and figures of BENSAID
  in brackets) as follows:
  Atlantoceras tataense (pl. 1, figs 3-3b, the holotype); Mzerrebites juvenocostatus (pl. 3, fig. 3);
  Pharciceras aff. tridens (Ph. tridens, pl. 5, fig. 1 1); Afromaenioceras crassum (pl. 2, figs 1 1, 1 la,
  the holotype, pl. 4, figs 6, 6a, pl. 6, fig. 9); Afromaenioceras sulcatostriatum; Afromaenioceras n. sp.
  (Maenio. cf. crassum, pl. 1, figs 10, 10a); Maenioceras n. sp.  II (Maenio. terebratum, pl. 1, fig. 1 1);
  Wedekindella lata (pl. 3, figs 1, la, the holotype); "Phoenixites" n. sp. (Tornoceras simplex);
  "Trevoneites" sp. (Tornoceras westfalicum)