An enigmatic Corydoras

9. March 2016

obtained corys from Brazil, which had been collected in the upper
Amazon. The exporter had identified them as Corydoras evelynae. Indeed
the upper Amazon is type locality of C. evelynae; this species has a
dark band over the back, which is broken in pieces; under the dorsal fin
is a broad, rectangular spot that looks quadratic when watched from
above; the dorsal spine is dark; on the flanks are two thin, parallel
running horizontal bands; the species has a dark eye-band (this
description bases on the holotype specimen). Since the first
description, which was made in 1963 on the basis of only one specimen,
Corydoras evelynae is subject of many speculations and has become
imported only very rarely.

new importations show some similarities with C. evelynae, but also many
differences. They look most similar to the fish that have been named
C20 in 1994. The number C20 has been eliminated later, because it is
thought to represent only the juvenile of C. arcuatus.

our largest C20 imported now show clearly that they do not belong to
Corydoras arcuatus. C. arcuatus of similar size (about 4 cm long) from
Peru look totally different, are regarded as large already in the trade
and have, of course, the species-specific pattern.

cannot exclude the possibility that C20 represents a juvenile stage of
the so-called Super-Arcuatus from Brazil, a scientifically undescibed,
very large (up to 8 cm) species; however, we do not think that this is
very much likely.

juvenile specimen (about 2 cm long) of Corydoras evelynae from
Colombia, which we obtained as a sample specimen from the Rio Vaupes in
May 2015 already showed the typical pattern of C. evelynae as described
above. So it can be excluded that C. evelynae has a long-lasting
juvenile pattern that differs from the adult pattern.

cannot decide wether our new importations represent specimens of C20 or
of a totally new species of Corydoras. In any way they are pretty
members of the genus that have a pattern similar to that of C. evelynae,
but a body shape that reminds one in the Corydoras-loretoensis-group.

our customers: the fish have code 229542 on or stocklist. Please note
that we exclusively supply the wholesale trade. Available in very small
numbers only!

Text & photos: Frank Schäfer