Diagnosis: Luciobarbus numidiensis is distinguished from other Luciobarbus species from the African Mediterranean Sea basin by a combination of characters, none of them unique (Ref. 121680). It is distinguished from L. callensis by having a longer anal fin, 19-23% of standard length vs. 16-19%, a wider anal-fin base, 6.5-10% of standard length vs. 6.5-8%, and a longer distance between the pectoral and pelvic-fin origins, 27-30% of standard length vs. 22-29%; it is distinguished from L. setivimensis by having a longer pectoral fin, 74-94% of head length vs. 69-84%, a longer predorsal length, 49-55% of standard length vs. 46-52%, a wider caudal peduncle depth, 12-14% of standard length vs. 11-13%, and a smaller eye diameter, 11-22% of head length vs. 11-28% (Ref. 121680). It is distinguished from Luciobarbus guercifensis by having thin barbels vs. thick, the rostral-barbel origin placed clearly behind the tip of the snout vs. rostral-barbel origin at the extreme anterior of the snout; it is distinguished from L. chelifensis, L. mascarensis and L. leptopogon by having 43-47 + 1-2 lateral line scales vs. 41-43 + 1-2 in L. chelifensis and L. leptopogon, usually 41 + 1-2 in L. mascarensis (Ref. 121680). Luciobarbus numidiensis is further distinguished from L. chelifensis and L. rifensis by having a longer anal fin, 19-22% of standard length vs. 17-19% in L. chelifensis and 16-19% in L. rifensis; it is distinguished from L. leptopogon by having a greater caudal peduncle depth, 12-14% of standard length vs. 10-13%, and from L. yahyaouii by having a longer distance between the pelvic and anal-fin origins, 23-26% of standard length vs. 20-24% (Ref. 121680). It is also distinguished from L. mascarensis, L. lanigarensis and L. yahyaouii by having a shorter predorsal length, 48-55% of standard length vs. 53-58% in L. mascarensis, 54-59% in L. lanigarensis and 53-57% in L. yahyaouii; it is also distinguished from L. lanigarensis by having a smaller prepelvic length, 49-56% of standard length vs. 55-60%, a greater postorbital length, 46-52% of head length vs. 42-48%, and the last unbranched dorsal-fin ray ossified and serrated at 2/3 of its length vs. last unbranched dorsal-fin ray serrated along almost its entire length (Ref. 121680).

Description: A large-sized species with a moderately long head; body deepest at dorsal-fin origin or about midline between nape and dorsal-fin origin; depth decreasing continuously towards caudal-fin base; greatest body width in front of dorsal-fin origin (Ref. 121680). Caudal peduncle compressed, 1.2-1.5 times longer than deep (Ref. 121680). Section of head roundish, flattened on ventral surface; snout rounded; mouth inferior (Ref. 121680). Dorsal-fin origin situated above pelvic-fin origin; anal-fin origin slightly behind vertical of middle between dorsal and caudal-fin origins; anal fin reaching to caudal-fin base; pectoral fin reaching 60-80% of distance between pectoral- and pelvic-fin origin; pelvic fin not reaching vertical of tip of last dorsal-fin ray when folded down; pelvic fin reaching to 60-90% of distance between pelvic- and anal-fin origins; posterior dorsal-fin margin straight or slightly concave; posterior pectoral and anal-fin margins convex; caudal fin forked with rounded lobes of equal length; dorsal fin with 4 or 5 unbranched and 8.5 branched rays, last unbranched ray serrated along most its entire length; anal fin with 3 unbranched and 5.5 branched rays; pectoral fin with 13-18 rays and pelvic fin with 8 rays (Ref. 121680). Lateral line with 43-47 scales on flank and 1-2 scales on caudal-fin base; between dorsal-fin origin and lateral line8.5-9.5 scale rows and 5.5-6.5 scale rows between pelvic-fin origin and lateral line (Ref. 121680). Pharyngeal teeth in three rows: 4+3+2 (Ref. 121680). On first gill arch, 3-4 gill rakers on upper and 8-10 on lower limb (Ref. 121680).

Colouration: In life, whitish-golden on belly, silver-grey on flank and dark grey on back; head golden-grey and cheeks greenish-golden; all fins grey; pectoral fin with a golden distal edge (Ref. 121680).