Classification / Names
Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa
Teleostei (teleosts) >
Characiformes (Characins) >
Crenuchidae (South American darters) > Characidiinae
Etymology: Characidium: Diminutive of Charax, -akos = a fish without identification (Ref. 45335); summum: From the Latin summus, which means high, elevated, alluding to the high altitude where the species occurs, near Pico Tracoá, higher than 1100 m above sea level in the Serra dos Pacaás Novos (Ref. 104900).
Environment: milieu / climate zone / depth range / distribution range
Ecology
Freshwater; benthopelagic; pH range: ? - 3.6. Tropical; ? - 22°C
South America: only known from upper rio Pacaás Novos, a tributary of rio Mamoré, rio Madeira basin, Rondônia State, Brazil (Ref. 104900).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 4.2 cm SL male/unsexed; (Ref. 104900)
Short description
Identification keys | Morphology | Morphometrics
Dorsal spines (total): 0; Dorsal soft rays (total): 11 - 13; Anal spines: 0; Anal soft rays: 8 - 9; Vertebrae: 36. Diagnosis: Characidium summus is a unique species among congeners by lacking an adipose fin and having a complete lateral line; can be further distinguished from congeners, including C. vestigipinne, that have complete lateral line and adipose fin absent, vestigial or reduced by the absence of dark bars or spots on head, body or fins, except for a dark blotch immediately on the rear of opercle, a narrow midlateral dark stripe (less than half scale deep), and a dark basicaudal spot (Ref. 104900).
The rio Pacaás Novos is a black water river, with moderate water current and predominantly rocky bottom; specimens of C. summus were sampled in small puddles (1-4 m wide and 1.5 m deep) and laterally in the river backwaters (Ref. 104900).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Zanata, A.M., L.M. Sarmento-Soares and R.F. Martins-Pinheiro, 2015. A new species of Characidium Reinhardt (Ostariophysi: Characiformes: Crenuchidae) from coastal rivers in the extreme south of Bahia, Brazil. Zootaxa 4040(3):371-383. (Ref. 104900)
IUCN Red List Status (Ref. 130435: Version 2024-1)
Threat to humans
Harmless
Human uses
Tools
Special reports
Download XML
Internet sources
Estimates based on models
Phylogenetic diversity index (Ref.
82804): PD
50 = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01230 (0.00479 - 0.03160), b=3.00 (2.77 - 3.23), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref.
93245).
Trophic level (Ref.
69278): 3.3 ±0.3 se; based on size and trophs of closest relatives
Fishing Vulnerability (Ref.
59153): Low vulnerability (10 of 100).