Mayaheros urophthalmus and its subspecies from Yucatan

[cichla]

Several Subspecies or Phenotypic Plasticity? A Geometric Morphometric and Molecular Analysis of Variability of the Mayan Cichlid Mayaheros
urophthalmus in the Yucatan. by Barrientos-Villalobos et al. 2018. Copeia 106(2): 268–278.

Abstract: The Mayan Cichlid (Mayaheros urophthalmus) is usually considered to be a complex of 18 subspecies, most of which are endemic to the Yucatan Peninsula and were diagnosed by phenetic analyses based on traditional morphometrics and color pattern. However, morphological differences can be due to environmental conditions rather than taxonomic distinctiveness. We evaluated, by means of a geometric morphometric analysis, two hypotheses for shape differences in 20 natural populations of M. urophthalmus, including five subspecies recently raised to species status: M. alborus, M. cienagae, M. conchitae, M. mayorum, and M. zebra. The geographical distribution and three types of aquatic environment (River, Lagoon or Pond, and Cenote) were used as classificatory variables. In addition, a molecular analysis of two concatenated fragments of mitochondrial DNA (mtDNA), cytochrome b (cytb) and cytochrome oxidase subunit I (COI), showed genetic differentiation among some populations (FST ¼ 0.36). Whereas the geometric morphometric analysis found significant differences among all aquatic environments, patterns of body shape of M. urophthalmus are more consistent with ecophenotypic variation than with genetic differentiation due to geographic isolation by distance. We think that there is currently no evidence to raise the traditionally recognized subspecies of M. urophthalmus to the species level.

[DRE]

Thanks.

Where was this described?
"...recently raised to species status: M. alborus, M. cienagae, M. conchitae, M. mayorum, and M. zebra."

I.e.e where were those species first described?

[Bas Pels]

I wonder, in many cases species are describerd nowadays because they differ more than a certain percentage in their DNA form other speceis.

Or, in all honesty, as just a few pieces of DNA are sampled, in case here sufficient difference is found.

Apart from the question whehter this results in valid species in all cases, here we are speaking about a species (M uropthalmus) whiuch is rather polymorfic. In such a case a found difference could well be within the normal range of differneces, in case sufficient material would have been studied.

That is, unless enough data is presented I don´t think we shoud consider the new `species` as valid.

[cichla]

M. alborus, M. cienagae, M. conchitae, M. mayorum, and M. zebra.
I.e.e where were those species first described?”

These (sub-)species were described by Hubbs (1936). Kullander (2003) and Rican et al. (2015) treated all as valid species. The current paper by Barrientos-Villalobos et al. (2018) reveals, however, that these are synonyms.