Pseudobarbus skeltoni Chakona & Swartz, 2013
Giant redfin

Family:  Cyprinidae (Minnows or carps), subfamily: Smiliogastrinae
Max. size:  16.34 cm SL (male/unsexed)
Environment:  benthopelagic; freshwater,
Distribution:  Africa: Breede River system, South Africa (Ref. 93872).
Diagnosis:  Dorsal spines (total): 0-0; Dorsal soft rays (total): 10-12; Anal spines: 0-0; Anal soft rays: 8-8; Vertebrae: 36-38. Diagnosis: Pseudobarbus skeltoni reaches the largest size of any Pseudobarbus species and is distinguished from its congeners, except P. burchelli and P. burgi, by possessing two pairs of prominent oral barbels (Ref. 93872). It is distinguished from P. burchelli and P. burgi by the combination of the following features: distinctive terminal mouth in adults vs. subterminal in all size classes of P. burchelli and P. burgi; juveniles, sub-adults and young adults of P. skeltoni have subterminal mouths, but their lower lips are unretracted and they lack the cartilaginous plate found in both P. burchelli and P. burgi; a typically longer head relative to standard length, being 30.5% vs. 26.8% in P. burchelli and 25.8% in P. burgi; shaloow head depth, being 64.2% of head length compared to 70.1% of head length in P. burchelli and 74.1% of head length in P. burgi; mature sexually active males develop two clusters of large conical tubercles on the snout, with 22-30 tubercles in each cluster, vs. 5-10 tubercles per cluster in P. burchelli and 10-15 tubercles per cluster in P. burgi; multiple rows of large conspicious tubercles above each nare and antero-dorsal edge of each orbit, vs. single row in congenres (Ref. 93872). Description: Body fusiform, dorsal surface slightly convex and ventral surface flattened from anterior base of pelvic fins to tip of lower lip; head relatively large and slightly depressed; head length greater than body depth (Ref. 93872). Adults have distinct terminal mouths; juveniles, sub-adults and young adults have inferior mouths, but lower lip unretracted and lack cartilaginous plate (Ref. 93872). Two pairs of simple and well-developed barbels, both pairs are longer than the orbit diameter in adults (Ref. 93872). Eyes relatively small, located dorsolaterally, closer to tip of snout than to the caudal margin of gill cover, interorbital profile flat, and snout prominent (Ref. 93872). Distal margin of dorsal fin slightly concave with 3 or 4 simple and 7 branched rays, anterior base of dorsal fin is inserted slightly posterior to the origin of pelvic fins; anterior base of dorsal fin generally closer to base of caudal fin than tip of snout (Ref. 93872). Pectoral fin fan-shaped, with 13 or 14 rays, shorter than head length, almost reaching anterior base of pelvic fin in males, but only reaching slightly beyond halfway to anterior base of pelvic fin in females (Ref. 93872). Posterior edge of pelvic fin gently rounded with 8 rays, shorter than head length, reaching the anus in males and reach within two scales from the anus in females (Ref. 93872). Distal margin of anal fin almost straight, with 3 simple and 5 branched rays, origin closer to anterior base of pelvic fin than caudal fin base (Ref. 93872). Anus situated near the base of the anal fin (Ref. 93872). Caudal fin is forked, length shorter than head length (Ref. 93872). Scales moderately large; lateral line complete, perforating 36-39 scales; 6 or 7 scale rows between lateral line and anterior base of dorsal fin; 5 or 7 scale rows between lateral line and anterior base of pelvic fin; and 4-6 scale rows between lateral line and anterior base of anal fin; predorsal scales 17-21, smaller than flank scales, embedded in skin, with numerous small tubercles extending from nape to anterior base of dorsal fin; 15 to 18 circumpeduncular scales (Ref. 93872). Naked patch between head and posterior base of pectoral fins, scales between posterior end of pectoral fins and anterior end of pelvic fins reduced and embedded; scales between nape and anterior base of dorsal fin embedded; axillary scales of pelvic fin not prominent or elongate (Ref. 93872). Colouration: In fresh specimens, body olive to golden-tan dorsally and laterally, becoming lighter ventrally (Ref. 93872). Base of fins yellowish-orange with red patches in some specimens; juveniles and subadults have well marked spots above lateral line, but spots are absent in adults (Ref. 93872). Alcohol preserved specimens are dark greyish dorsally and laterally and ash grey or whitish ventrally; black spots present above lateral line in juveniles and sub-adults, but spots are absent in adults (Ref. 93872).
Biology:  Reproduction is unknown, but spawning possibly occurs around November-December, based on the observation that males had large tubercles; juveniles and sub-adults probably feed by picking prey or algae from rock; adults have more predatory lifestyle and are possibly water column feeders (Ref. 93872).
IUCN Red List Status: Endangered (EN); Date assessed: 06 December 2016 (B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)) Ref. (130435)
Threat to humans:  harmless


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