A Seasonal Study Reveals the Occurrence of Exotic Rotifers,the River Antigua,Veracruz, Close to the Gulf of Mexico |
| |
Authors: | S. Nandini S. S. S. Sarma R. D. Gulati |
| |
Affiliation: | 1. Laboratorio de Zoología Acuática, Universidad Nacional Autónoma de México, Mexico;2. Department of Aquatic Ecology, NIOO/Netherlands Institute of Ecology, Wageningen, The Netherlands |
| |
Abstract: | Zooplankton studies in Mexican rivers are few despite the fact that Mexico has >200 rivers. We present data on the seasonal diversity of rotifers during 2013–2014 from the river La Antigua, near Veracruz. We collected samples from 15 stations along a horizontal gradient of ~5 km, from the upper reaches to about 2 km from the sea. The physico‐chemical variables analysed were temperature, pH, dissolved oxygen, conductivity, nitrates, phosphates, Secchi depth and salinity. From each site, 80 L of water was filtered with a 50‐μm plankton net. Rotifers were identified and quantified using a Sedgewick Rafter cell. The river is shallow (maximum depth 2.5 m during the rainy season). Our observations indicated that the phytoplankton community was dominated by diatoms; the chlorophyll a concentrations ranged from 0.55 to 26.1 μg L?1 over the study period. We found >125 rotifer species belonging to 21 families, mostly from the Lecanidae, Brachionidae, Notommatidae and Lepadellidae. The density of rotifers was low, <40 ind. L?1, but species diversity (Shannon–Wiener) ranged, except for a onetime minimum of 0.25, from 2.0 to 4.0 for most part of the year. We also encountered Notholca cf. liepetterseni , an endemic species to Europe and Lecane yatseni , endemic to Asia. Other new records included Lecane rhytida and Ptygura melicerta . The importance of long‐term studies in rivers is emphasized. Copyright © 2017 John Wiley & Sons, Ltd. |
| |
Keywords: | zooplankton diversity rivers Mexico |
|
|