On the ecology of Cletocamptus gomezi Suárez-Morales, Barrera-Moreno & Ciros-Pérez 2013 (Crustacea, Copepoda, Harpacticoida) micro-endemic to Lake Alchichica, Central Mexico

摘要

Cletocamptus gomezi Suárez-Morales, Barrera-Moreno & Ciros-Pérez (2013) is a recently described new species of meiobenthic Harpacticoida copepod, micro-endemic to Lake Alchichica, Puebla, Central Mexico. Cletocamptus gomezi lives in saline water (K25 =12.6 mS cm-1) dominated by sodium, magnesium, chloride, and bicarbonate ions and markedly alkaline (pH 9.0±0.1). Cletocamptus gomezi occurs in a depth range of surface to 10 m with preference to shallow (20oC) waters; fine sandy sediments (2.3 ?), rich in organic matter (8.4%) and carbonate concentrations (29%), and abundant aquatic vegetation coverage. In the littoral zone the average density and biomass of Cletocamptus gomezi reaches 4106±10,962 ind m-2 and 3.66±9.75 mg C m-2. Below 3 m, along the lake’s slope, the density reduces dramatically down to 265±593 ind m-2 and 0.23±0.51 mg C m-2 at 10 m. Cletocamptus gomezi is absent below 10 m down to 62 m, the maximum depth of the lake. Spatially, except L3 (whose density and biomass values are the lowest) that differs (P0.5). Temporally, there are no statistical differences (P>0.5) in density or biomass. The fact of finding Cletocamptus gomezi far away from the coast line (>100 km) and at high altitude (2335 m asl) is uncommon since most reports of Cletocamptus are from coastal brackish waters, and consequently, at sea level. Migrating waterbirds, as dispersal agents could be the explanation of Cletocamptus gomezi successfully inhabiting Lake Alchichica. Cletocamptus gomezi shares the same habitat with dense populations of tubificid oligochaetes, amphipods, leeches, chironomids, and nematodes. The disappearance of Cletocamptus gomezi habitat by the lake’s -natural and mostly anthropogenic- desiccation process, seriously threatens the survival of this and the other numerous micro-endemic species of Lake Alchichica.