Conference Paper
Phylogeographical convergence between two troglobitic organisms in the Sierra de El Abra
Kopp, J., Coppola, J. and Espinasa, L.
Record Number:
3268
Year:
2017
Journal:
AIM 2017
Abstract:
Many authors assume that the multiple populations of Astyanax
mexicanus from Sierra de El Abra and Sierra de Guatemala derived from several independent
colonizations, despite both Sierras being a continuous karstic area. They have inherently assumed
there are effective barriers that prevented troglobite migration between caves, generating separate
biogeographical areas.
Previous studies using the 16S rRNA and its calibrated molecular clock have shown that
Anelpistina quinterensis, a troglomorphic silverfish insect, was able to migrate underground to
reach both mountain ranges within the last 12,000 years. Thus, the Servilleta canyon that separates
both Sierras has not been an effective biological barrier that prevented underground migration of
troglobites. In the current study we have sequenced the DNA of an aquatic troglobite, the mysid
shrimp Speleomysis quinterensis, whose biogeography overlaps with that of Astyanax. Specimens
were collected from Sierra de Guatemala (Caballo Moro cave) and from Sierra de El Abra (Pachon,
Tinaja, and “Chiquitita” caves). Chiquitita cave is a new and previously unpublished locality with
Astyanax. This new locality becomes the southernmost locality of the El Abra area with Astyanax
mexicanus, and the 32nd cave with troglobitic Astyanax.
Histone DNA sequences from Pachon and Chiquitita troglobitic mysid shrimps are identical,
supporting that aquatic troglobites dispersed between the northernmost and the southernmost of
Sierra de El Abra in recent geological times. But there is also evidence that Tinaja mysid shrimps
derived from an independent phyletic line, implying two separate evolutionary histories. The
phylogeography of the mysids is in agreement and overlaps with the mitochondrial
phylogeography of Astyanax cavefish. This convergence supports that caves in the central area of
Sierra de El Abra, where Tinaja cave is located, had effective barriers that modulated evolutionary
histories across multiple aquatic troglobitic species.
Times Cited:
1
Relevent Species: