The Rio Xingu in SE Brazil is home to an astounding number of species of loricariids, and given that this habit is believed to be under destruction due to the world's largest hydro-electric dam being constructed, the fish fauna has been under more intense study over the past few years. Several incredibly beautiful plecos and freshwater rays are endemic to this river.
For those who may not be familiar with the "L" numbers, this is a system developed some years ago where collected loricariids that appear to be new species are catalogued with a number awaiting formal description and naming. A similar system is in place for Corydoras using the letter "C" obviously.
The article here http://www.reef2rainforest.com/2016...campaign=2016_10_21+Amazonas&utm_medium=email
outlines the description of L066 and L333 as one distinct species. The abstract of the scientific paper is cited below; the full paper is linked in the article but you need to pay to access it (I didn't).
The diversity of Hypancistrus species in the Xingu River is remarkable and the variation in color morphs represents a real challenge to taxonomists to delimit species boundaries. One of the most recognizable Hypancistrus complexes is the worm-lined species, known in the aquarium trade as King Tiger Plec in English, Hypancistrus“pão” in Portuguese or under the L-numbers L066 and L333 that represent two melanic pigment pattern phenotypes. To assess the identity of these two phenotypes, we described their karyotypes and sequenced part of the mitochondrial cytochrome oxidase I gene (DNA barcode). These fishes have 52 chromosomes (40 meta-submetacentric and 12 subtelo-acrocentric) and a strong heteromorphism in chromosome pair 21 was observed, which does not correlate with the two phenotypes or sex. DNA barcodes separated the samples analyzed fromHypancistrus zebra and other publicly available sequences of Loricariidae showing no divergence between the two phenotypes. The data set indicates that worm-lined Hypancistrus from the Xingu form a single species with clear chromosomal and melanic pigment pattern polymorphisms.
For those who may not be familiar with the "L" numbers, this is a system developed some years ago where collected loricariids that appear to be new species are catalogued with a number awaiting formal description and naming. A similar system is in place for Corydoras using the letter "C" obviously.
The article here http://www.reef2rainforest.com/2016...campaign=2016_10_21+Amazonas&utm_medium=email
outlines the description of L066 and L333 as one distinct species. The abstract of the scientific paper is cited below; the full paper is linked in the article but you need to pay to access it (I didn't).
The diversity of Hypancistrus species in the Xingu River is remarkable and the variation in color morphs represents a real challenge to taxonomists to delimit species boundaries. One of the most recognizable Hypancistrus complexes is the worm-lined species, known in the aquarium trade as King Tiger Plec in English, Hypancistrus“pão” in Portuguese or under the L-numbers L066 and L333 that represent two melanic pigment pattern phenotypes. To assess the identity of these two phenotypes, we described their karyotypes and sequenced part of the mitochondrial cytochrome oxidase I gene (DNA barcode). These fishes have 52 chromosomes (40 meta-submetacentric and 12 subtelo-acrocentric) and a strong heteromorphism in chromosome pair 21 was observed, which does not correlate with the two phenotypes or sex. DNA barcodes separated the samples analyzed fromHypancistrus zebra and other publicly available sequences of Loricariidae showing no divergence between the two phenotypes. The data set indicates that worm-lined Hypancistrus from the Xingu form a single species with clear chromosomal and melanic pigment pattern polymorphisms.
