Description:
Body and head depressed. Dorsal profile of body and
head convex from tip of snout to dorsal-fin origin,
slightly concave to straight from that point to origin
of adipose fin, concave from end of adipose fin to
origin of caudal fin. Ventral profile of body straight,
body height begins to decrease at pelvic girdle. Body
covered with bony plates except along dorsal-fin base
and ventral surface between tip of snout and anal-fin
origin. Median series with 22-24(13, 23*) lateral
plates; lateral-line canal complete and uninterrupted.
Three* predorsal plates, seven* plates at base of
dorsal fin, four* plates between dorsal and adipose
fins and 8*(6), 7(5) or 6(2) plates between adipose
fins and caudal fins. Fin rays and body plates covered
by small, caudally directed odontodes in regular rows,
larger on fin spines Widholzer,
R.L., et al. (2023).
Habitat: Known from three localities in the
Rio Vacacaí sub-basin of the Rio Jacuí
basin, laguna dos Patos hydrographic system. Colouration:
Body dark brown to black with pale yellow dots, usually
smaller than pupil diameter, along body; paired fins
with yellow dots, dorsal fin with few inconspicuous
light dots on unbranched ray, adipose and caudal fins
unmarked. Lighter brown bar on terminus of caudal
peduncle. Tip of upper and lower leading rays and
outer branched rays of caudal fin with conspicuous
yellow spots Widholzer,
R.L., et al. (2023). Aquarium
Care: The Ancistrus genera make
good community fish where they do not grow too big
for the aquarium. Some species have different requirements
in the aquarium so best to read up on the species
you have whereas if they need higher oxygen requirements
or not, or if they prefer cooler waters if they originate
from the southern parts of South America against the
species from further up north. Diet:
Algae-eater. Vegetable foods such as cucumber and
courgette and also tablet and meaty foods. Reproduction:
The female lays her eggs in caves or crevices... that
the male has chosen and cleaned.... as a cluster.
The male usually then guards the eggs after ejecting
the female. The fry then cling to the sides of the
cave and when they use up their yolk sac, which is
around the four to seven day period, they will be
ready to feed on infusuria, vegetable matter, brine
shrimp naupli or micro worms. In a community tank
a few will survive if enough hiding places are afforded
to them. (Prefers cooler waters). Etymology:
Latinised from Greek megas (megas), large, great and
akanthos (akanthos), thorn, spine, in reference to
the large pectoral-fin spines of the new species.
A noun in apposition.
Common
Name:
None
Synonyms:
None
Family:
Loricariidae
Distribution:
South America:
Three localities in the Rio Vacacaí sub-basin
of the Rio Jacuí basin, laguna dos Patos hydrographic
system, Brazil.
Size:
10.0cm. (4ins)
Temp:
22-25°c (71-77°f.)
p.H.
6.0-7.5.
Reference:
Fish
in the News(2024)
Widholzer RL, Borsoi J, Reis RE, Lehmann A. P.
A new species of Ancistrus (Siluriformes: Loricariidae),
with a redescription of Ancistrus brevipinnis and
further evidence of hidden diversity in the laguna
dos Patos system, Brazil. Neotrop Ichthyol. 2023;
21(4):e230078.
Ancistrus
megacanthus Holotype-Brazil, Rio Grande do Sul, São
Gabriel, Rio Vacacaí on road RS-630, tributary to Rio
Jacuí, laguna dos Patos system
Ancistrus
megacanthus Dorsal view-Holotype-Brazil, Rio Grande do Sul,
São Gabriel, Rio Vacacaí on road RS-630, tributary
to Rio Jacuí, laguna dos Patos system
Ancistrus
megacanthus Ventral view-Holotype-Brazil, Rio Grande do
Sul, São Gabriel, Rio Vacacaí on road RS-630,
tributary to Rio Jacuí, laguna dos Patos system
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