Journal Article
Subterranean waters of Yucatán Peninsula, Mexico reveal epigean species dominance and intraspecific variability in freshwater Ostracodes (Crustacea: Ostracoda)
Macario-González, L., Cohou, S., Angyal, D., Pérez, L. and Mascaró, M.
Record Number:
5197
Year:
2021
Journal:
Diversity
Volume:
13(2), 44
Abstract:
Abstract: The Yucatán Peninsula is a karstic region, rich in subterranean environments with a
diverse crustacean stygobiont fauna. In order to gain insights into the biological evolution of the
subterranean environments of this region, we evaluated the ostracode species composition of caves
and cenotes in five independent sampling campaigns (2008, 2013, 2017–2019). Using morphometric
analyses, we evaluated inter-population morphological variability; using molecular analysis based
on mitochondrial COI and nuclear 18S rDNA, we evaluated genetic differentiation in selected species.
The observed fauna is composed of 20 (epigean) species, presenting a lack of strict stygobionts.
Morphometric analyses discriminated up to three morphotypes in each of the three most abundant
species: Cytheridella ilosvayi, Alicenula sp. and Cypridopsis vidua. High intraspecific morphological
variability was found either in shape or size. Phylogenetic analysis based on COI demonstrated
the existence of three lineages on C. ilosvayi, with high support (>0.9). The 18S rDNA sequences
were identical among individuals of different populations. A lack of congruence between the genetic
markers precluded us from postulating speciation in subterranean environments. It is likely that
Late Pleistocene—Early Holocene climate variation related to sea level and precipitation was forcing
agent for epigean ostracode dominance in subterranean environments of the Peninsula.
Keywords: Ostracoda; Yucatán Peninsula; cenotes; mitochondrial marker; geometric morphometrics
Times Cited:
3