Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Characiformes
(Characins) > Crenuchidae
(South American darters) > Characidiinae
Etymology: Characidium: Diminutive of Charax, -akos = a fish without identification (Ref. 45335); samurai: Named for the Japanese warrior caste that provided the administrative and fighting aristocracy from the 11th to the 19th centuries. The samurais are known by their expertise in several kinds of martial arts. Currently, expertise in martial art is attested by the term'black belt', a condition inherent to that warrior caste. The name samurai was used herein in allusion to the conspicuous midlateral black band present in the new species. A noun in apposition.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic; depth range 1 - 2 m (Ref. 96872). Tropical
Sout America: Rio das Almas and rio Vermelho basins in eastern Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 4.7 cm SL male/unsexed; (Ref. 96872)
Morphology | Morphometrics
soft rays: 9 - 10;
Vertebrae: 34 - 35. Characidium samurai is distinguished from all its congeners, except C. lanei Travassos, by having a dark lateral band along the head and body that is particularly broad (1.5 or 2 scales wide) from the rear of head to the end of the caudal peduncle and by the absence of dark bars or blotches on the ventral half of the body. It can be diagnosed from C. lanei by having the lateral band with straight borders overall (vs. lateral band with somewhat irregular borders due to blotches slightly extending dorsally or ventrally), anal fin ii,7-8 (vs. ii,6), 4 horizontal scale rows above the lateral line and 4 below (vs. 5/3), and lacking dark pigmentation around the insertion of the dorsal-fin rays (vs. presence). It further differs from congeners that occur in Brazilian rivers by having a complete lateral line, isthmus completely covered by scales, 14 scales around the caudal peduncle, and presence of adipose fin. It can be further distinguished from congeners by the absence of dark bars or spots on the fins, except for a faded dorsal-fin bar and anal-fin rays ii,7-8. It differs from congeners from northeastern Brazilian rivers by having the following characters: aperture of the pseudotympanum enclosed between ribs of the fifth and sixth vertebrae; presence of the parietal branch of the supraorbital canal; two series of teeth on the dentary; and 7-11 premaxillary teeth; 7-8 branched anal-fin rays; 34-37 lateral-line scales; one faded dark bar on the proximal half of the dorsal-fin rays; absence of a blotch on the caudal peduncle, or blotch merged to the longitudinal bar; and ii,7-8 anal-fin rays (Ref. 96872).
Found in clear water streams with water running over rocks, pebbles, sand and/or muddy bottoms, at altitudes ranging from 17 to 177 m a.s.l. in habitats characterized mainly by moderate water current. The type locality where most specimens were collected has a width of about 2 m, deep of 1-2 m, medium to fast water currrent, muddy substrate and grassy river borders (Ref. 96872).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Zanata, A.M. and P. Camelier, 2014. A new species of Characidium (Characiformes: Crenuchidae) from small coastal drainages in northeastern Brazil, with remarks on the pseudotympanum of some species of the genus. Neotrop. Ichthyol. 12(2):333-342. (Ref. 96872)
IUCN Red List Status (Ref. 119314)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01122 (0.00514 - 0.02450), b=3.04 (2.87 - 3.21), in cm Total Length, based on all LWR estimates for this body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.4 ±0.3 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .