Journal Article
Diving in the sand: The natural history of Pygidianops amphioxus (Siluriformes: Trichomycteridae), a minature catfish of Central Amazonian streams in Brazil
Carvalho, M.R., Zuanon, J. and Ferreira, E.J.G.
Record Number:
3157
Year:
2014
Journal:
Environmental Biology of Fishes
Pages:
59-68
Volume:
97
PMCID:
hyyp://doi.org/10.1007/s10641-013-0123-9
Abstract:
Abstract The natural history of Pygidianops amphi-
oxus de Pinna and Kirovskyi (Neotropical Ichthyol-
ogy 9:493–504, 2011), a highly specialized sand-
dwelling catfish species, was studied based on un-
derwater observations in a small forest stream in the
central Amazon. Information on the feeding and
reproductive biology was obtained by means of
analyses of preserved specimens. These miniature
catfishes remained buried in the sand at the bottom
of the stream and were never observed swimming in
open water. The catfish consumed small benthic in-
vertebrates, particularly Chironomidae larvae and
Harpacticoida copepods, which were most likely
captured by suction feeding inside the sand banks.
Pygidianops amphioxus displays sexual dimorphism
in the shape of the urogenital papilla and in the body
length, with adult females being relatively longer
than males. Sexually mature females were found
throughout the year and carried a small number of
proportionally very large oocytes. A short duration
(24 h) experiment conducted in aquaria revealed that
these small catfishes exhibit the predominantly noc-
turnal habits typical of most Siluriformes.
Keywords Glanapteryginae . Psammophily.
Miniaturization . Tropical streams . Candiru
Times Cited:
2