First Insight into Groundwater Copepods of the Polish Lowland

Maciej Karpowicz,Sabina Smolska,Joanna Moroz,Magdalena Świsłocka

doi:10.3390/w13152086

Abstract

Our results are the first insight into groundwater copepods of the Polish Lowland. The sampling was conducted in 28 wells in north-eastern Poland, and Copepoda were present in 16 wells. We have identified six Copepoda species and one Cladocera. We have classified four species as stygophiles—Eucyclops serrulatus, Diacyclops bisetosus, Diacyclops crassicaudis, and Cyclops furcifer. These species were frequently found in studied wells of different regions of north-eastern Poland, often in high numbers, and females with egg sacs were observed. We present a detailed morphological description of these species, together with molecular characteristics based on mitochondrial DNA markers (COI gene) for E. serrulatus, D. bisetosus, and D. crassicaudis, and 12S ribosomal RNA for C. furcifer. We also present the development of abnormal structures in one specimen of D. crassicaudis, where the upper part of furcal rami was fused to form a single plate.

Highlights

Subterranean habitats fulfill the requirements of experimental model systems to address general questions in ecology and evolution [1]
We identified six Copepoda and one Cladocera species in the groundwater of north-eastern Poland
Most studied wells were dominated by one species, two species were found in six wells, and three species were found in two wells (Table 1)

Summary

Introduction

Subterranean habitats fulfill the requirements of experimental model systems to address general questions in ecology and evolution [1]. Groundwaters are populated by a specialized fauna called stygobionts and by accidental taxa (stygoxenes) temporarily imported from the surface. Stygophiles are intermediate between stygobionts and stygoxenes—they spend part of their life below ground and may even be more common in groundwater than in surface waters [2]. It is estimated that about 40% of the European crustacean fauna is represented by stygobiontic species, among which dominate copepods with about 1000 species and subspecies known from continental groundwater [3]. Most of them belong to the Harpacticoida (about 600 species) and Cyclopoida (about 300 species). Almost half of the newly described copepods are from groundwater habitats [3]

Methods

Results

Discussion

Conclusion