Stuart
Brown (1) Felipe
Alonso(1) Sebastián
Preisz (1) Enzo Edgardo Ferreyra
(3)
ScotCat
Sources:
Other
Sources:
Relevant
Information:
Habitat:
Otocinclus arnoldi inhabits clear waters
of the southern regions of South America so this should
be taken into account with temperature values in the
home aquarium. Lives in the same waters as Hoplisoma
paleatum and shares
the same colour pattern. A similar looking darker
species has been imported in the past from Uruguay.
Aquarium Care: Requires cool waters
in the aquarium as sustained high values can be problematic
for this species. A planted tank is best as it is
kind to plants but will keep the algae at bay. Can
be a bit territorial with other fish but do well together
in groups. Diet: Algae eater, tablet
foods, lettuce, flake and small live and frozen foods.
Etymology: The genus name Otocinclus:
oto-, ear; cinclus, latticework, referring to “post-temporal
bone pierced in a sieve-like manner, forming minute
tympana” (i.e., pterotic fenestrae, a character
shared to some extent by all loricariids). The specific
name arnoldi: This species was described
from “LaPlata” based on a single aquarium
specimen donated by Johann Paul Arnold, born in Germany,
1869-1952. Remarks:
The recent paper (2010) by Lehmann, P., F. Mayer and
R.E. Reis have resurrected Otocinclus arnoldi
from the La Plata basin from the synonymy of O.
flexilis Cope 1894from the Rio Jacuí,
Rio Grande do Sul in Brazil and is thus a species
in its own right based on three distinguishing features:
the possession of five branched pectoral-fin rays,
the larger number of enlarged odontodes on the tip
of the parieto-supraoccipital posterior process, and
having the prootic involved in the contact with the
hyomandibular articular condyle.
Common
Name:
None
Synonyms:
None
Family:
Loricariidae
Distribution:
South America:Argentina: tributaries of the lower Río
Paraná drainage, lower and middle rio Uruguai,
and the Río de La Plata. Type locality:
La Plata.
Size:
5.0cm. (2ins).
Temp:
20-24°c (67-75°f.)
p.H.
6.0-7.5.
IUCN
Red List
Despite
the little information available on this species, it
has a wide range and no apparent threats. Therefore,
it is assessed as Least
Concern (LC), (IUCN 2023).
Reference:
Lehmann,
P., F. Mayer and R.E. Reis,
2010. Re-validation of Otocinclus arnoldi Regan and
reappraisal of Otocinclus phylogeny (Siluriformes: Loricariidae).
Neotrop. Ichthyol. 8(1):57-68. Salvador, G.N. 2023. Otocinclus
arnoldi. The IUCN Red List of Threatened Species
2023.
Otocinclus
arnoldi Villa Elisa-La Plata Province, Buenos Aires,
Argentina
Otocinclus
arnoldi
Otocinclus
arnoldi
Otocinclus
arnoldi
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