Description:
Dorsal spines (total): 2; Dorsal soft rays (total):
7; Anal spines: 1; Anal soft rays: 4. This species
is distinguished by the following characters: teeth
bifid teeth (vs. spoon-shaped); dark spots on a light
background (vs light spots on a dark background or
not spotted); 4 rough lateral ridges on flanks (vs.
absent); 26-29 lateral series plates (vs. < 28
in several species, 31-32 in H.
laplatae); 1-2
plates bordering posterior margin of the supraoccipital
bone (vs. 3-4 in H. laplatae); differs from H.
affinis, H.
punctatus, H. ancistroides
by having inter-dorsal distance 14.4-19.5% in SL (vs.
18.9-21.0%); head depth 49.0-71.6% in HL (vs. 48.2-49.9);
differs from H. spiniger by having fine lateral
ridges with odontodes posteriorly inclined (vs. large
lateral ridges with odontodes in all directions),
weak lateral ridges in caudal peduncle (vs. strong),
mid lateral ridge from first plate (vs. ridge from
2nd or 3rd plates); adult of this species (> 12.0
cm SL) can be distinguished from adult H. spiniger
by having a strong ridge on temporal plate (vs. very
week). The Hypostomus genus has 7 rays to
the dorsal fin whereas the similar looking Pterygoplichthys
species have 10 dorsal fin rays. Habitat:
This species is quite abundant in the La Plata region
in the estuarine waters and in the arroyos and laguna's.
Occurs in rivers where substrate from which specimens
were obtained was composed chiefly of muddy sand.
This species was found in moderately oxygenated waters
(6.1-9.1 mg/l) with moderate current; water turbidity
23.7-442 NTU, conductivity 1.087-2.654 ?S/cm, pH 7.2-9.2,
and temperature 16.8-27.8°C. (Cardoso, Y. P. et.
al. 2019). Reproduction: Spawns between
November and February in the ponds and small lagoons.
The youngsters feed on the organic material found
on the muddy bottom. Aquarium Care:
As with most of this genus, will do well in a larger
aquarium which is well filtered. Water parameters
can be quite diverse for this genera. Diet:
Omnivore with a liking for green, tablet and frozen
foods.
South America:
Middle and lower Paraná and Uruguay River basins;
Laguna dos Patos basin. Type locality:
La Plata River, Uruguay.
Size:
60.0cm. (24ins)
Temp:
22-25°c (71-77°f.)
p.H.
6.5-7.2.
Reference:
Burgess, W.E.
1989 An atlas of freshwater and marine catfishes.
A preliminary survey of the Siluriformes. T.F.H. Publications,
Inc., Neptune City, New Jersey (USA). 784 p. Cardoso, Y. P., F. Brancolini,
L. Protogino, A. Paracampo, S. Bogan, P. Posadas and
J. I. Montoya-Burgos, 2019.
An integrated approach clarifies the cryptic diversity
in Hypostomus Lacépède 1803 from the
Lower La Plata Basin. Anais da Academia Brasileira
de Ciéncias 91(2):e20180131: [1-25].
Ferraris, C.J. Jr., 2007. Checklist
of catfishes, recent and fossil (Osteichthyes: Siluriformes),
and catalogue of siluriform primary types. Zootaxa
1418:1-628. Froese, R. and D. Pauly.
Editors. 2019. FishBase. World Wide Web electronic
publication. www.fishbase.org, ( 12/2019 ).
Hypostomus
commersoni Berisso-Buenos Aires Province, Argentina
Hypostomus
commersoni Cerro Largo Department, Uruguay
Hypostomus
commersoni Cerro Largo Department, Uruguay
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