Metynnis fasciatus?

AquaBarb

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Picked up some silver dollars today at my LFS. They were labelled up has Striped silver dollars
20220305_202345.jpg

Am i right in thinking these are also known in the hobby has Tiger Silver dollars or are they a different variety?
20220305_202312.jpg
 

Byron

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Taxonomic confusion is rife in the literature dealing with Metynnis species. There are 28 nominal species and only 16 are recognized as valid. The elevated number of synonyms is probably a consequence of the enormous variability of body shape and color pattern, which in turn are highly influenced by ontogeny and sexual dimorphism (Zarske & Géry, 1999; Jégu, 2003; Pavanelli et al., 2009; Ota et al., 2013; Ota et al., 2016).

The taxonomy of the genus is still confused and impeded by high ontogenetic variability and sexual dimorphism that includes the presence versus absence of the anal-fin lobe, the elongation of the first dorsal-fin rays, and variation in body coloration (Zarske & Géry, 1999; Pavanelli et al ., 2009; Ota et al ., 2013).

M. fasciatus was initially described as a distinct species by Ahl in 1931, but the loss of the type specimens caused later biologists to question whether this was a valid species or the type specimens had been juveniles of another species (which do show stripes, at least sometimes). Zarske & Gery (1999) sorted this out and confirmed the distinct species.

The photos above would seem to be M. fasciatus.
 

itiwhetu

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Taxonomic confusion is rife in the literature dealing with Metynnis species. There are 28 nominal species and only 16 are recognized as valid. The elevated number of synonyms is probably a consequence of the enormous variability of body shape and color pattern, which in turn are highly influenced by ontogeny and sexual dimorphism (Zarske & Géry, 1999; Jégu, 2003; Pavanelli et al., 2009; Ota et al., 2013; Ota et al., 2016).

The taxonomy of the genus is still confused and impeded by high ontogenetic variability and sexual dimorphism that includes the presence versus absence of the anal-fin lobe, the elongation of the first dorsal-fin rays, and variation in body coloration (Zarske & Géry, 1999; Pavanelli et al ., 2009; Ota et al ., 2013).

M. fasciatus was initially described as a distinct species by Ahl in 1931, but the loss of the type specimens caused later biologists to question whether this was a valid species or the type specimens had been juveniles of another species (which do show stripes, at least sometimes). Zarske & Gery (1999) sorted this out and confirmed the distinct species.

The photos above would seem to be M. fasciatus.
Out of interest. When you make a post like this do you do it out of memory (which can I say is impressive), or do you do a copy and paste from google (not so impressive)
 

Byron

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Out of interest. When you make a post like this do you do it out of memory (which can I say is impressive), or do you do a copy and paste from google (not so impressive)

The data comes from my series of profiles of freshwater fish and plant species that I wrote for another forum in 2010-2012 when they were building a knowledge section and asked me to manage it. TFF prohibits links to other forums (rightly so, I agree) so I copy/paste the relevant data from my own original copies of the profiles rather than linking the profiles themselves. I usually check scientific sources (like the Eschmeyer's Catalog of Fishes maintained by the California Academy of Science) for any updates ( a lot of research can occur in more than a decade).

The source of the information in my profiles was/is all scientific. Seriously Fish, Planet Catfish, Loaches Online, CorydorasWorld, etc. I also had/have an online relationship with several ichthyologists and biologists. I never use Google. I do use Google Scholar to find scientific papers, then I use the data from those if relevant. All the data I use is from accredited scientific sources, always.
 

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