A new blind cave fish population of genus Astyanax: geography, morphology and behavior

A local duplication of theMelanocortin receptor 1locus inAstyanax

“…We implemented a standard degenerate PCR approach to amplify a fragment of the Mc1r gene in wild-caught individuals from the Guerrero locality (Espinasa et al 2001). We initially sought to determine if Mc1r coding mutations were present in southern Guerrero cavefish populations, as had been discovered in closely-related cavefish species of the Sierra de El Abra region to the north (Gross et al 2009).…”

“…We initially sought to determine if Mc1r coding mutations were present in southern Guerrero cavefish populations, as had been discovered in closely-related cavefish species of the Sierra de El Abra region to the north (Gross et al 2009). Similar to El Abra populations, the Granadas locality harbors both cave- and surface-dwelling morphs, and the cave-dwelling forms are depigmented (Espinasa et al 2001). Because Mc1r has only been reported as a single-exon gene in fish (Logan et al 2003), we cloned this fragment from genomic DNA using a gradient series of three annealing temperatures ranging from ~48°C – ~70°C (Fig.…”

“…We cloned a ~820 bp sub-fragment of the Mc1r open reading frame using degenerate PCR from 11 wild-caught, cave-dwelling individuals and 12 wild-caught, surface-dwelling individuals ( A. aeneus ) from the Granadas cave and stream localities in Guerrero, Mexico (Espinasa et al 2001). We utilized the following degenerate primers to successfully clone a fragment of Mc1r from Astyanax aeneus specimens: degen Mc1r _F1: 5′-GGGCCTGATCTCCTGGTNGARAAYAT-3′; degen Mc1r _R1: 5′-GGGGGTCGATCAGAGTTRCADATDAT-3′; degen Mc1r _R2: 5′-CAGGATCAGGATCGCARRAARAANGG-3′.…”

“…In this study, we investigated the sequence structure of a natural population of Astyanax aeneus cavefish collected from the Granadas cave, in the state of Guerrero, in southern Mexico (Espinasa et al 2001). These fish are closely related to the blind cave-dwelling Astyanax mexicanus characins that populate the Sierra de El Abra ~1100 km to the northeast (Avise and Selander 1972; Ornelas-García et al 2008; Oliveira et al 2011).…”

Typological thinking strikes again

“…Proudlove, not only assigns a ''new'' species status to the cave populations but even claims that all those populations that are the result of different invasions should have different specific names for themselves (p. 53). Given that there are more than 30 cave populations of Astyanax in the same area of Mexico some even having eyes and pigmentation, others ''intermediate'' (two at least the result of introgressive hybridization) in morphs (Espinasa et al 2001), that would lead to an incredible confusion of names without a biological basis. Proudlove's reasoning is that there are enough different autapomorphies to name both morphs as different species.…”