What´s in the tank? Nematodes and other major components of the meiofauna of bromeliad phytotelms in lowland Panama

Abstract

BackgroundNematodes are a very diverse and extremely abundant group of animals, but their occurrence in the tropics is surprisingly little understood. We investigated the meiofauna of epiphytic tank bromeliads in the lowlands of Panama with particular emphasis on nematodes.ResultsWe encountered 89 morphospecies of nematodes in 54 bromeliad tanks, which were sampled in the wet and the dry season. Rotifers were by far the most abundant group in both the dry and the wet season (with up to 960 individual ml−1), followed by nematodes, annelids and harpacticoid copepods. Individual plants hosted up to 25 nematode species. These nematodes represented a diversity of feeding guilds, suction-feeders and deposit-feeders being most abundant. The relative abundances of feeding-types of nematodes differed considerably in the wet and dry season. Both species richness and abundance were strongly correlated with the size of the phytotelms and the season, while species diversity assessed with the Shannon-index was affected by neither of the two.ConclusionThis is the first study with a particular focus on the diversity of nematodes in tank bromeliads. We document a meiofauna of considerable abundance and diversity, which suggests important functional roles in ecological processes such as decomposition, which in turn warrants further study.Electronic supplementary materialThe online version of this article (doi:10.1186/s12898-016-0069-9) contains supplementary material, which is available to authorized users.

Environmental control of the microfaunal community structure in tropical bromeliads

“…In French Guiana, protozoan richness increases with bromeliad water volume and their densities were positively associated with rotifer and macroinvertebrate densities (Carrias et al, 2001). A contrasting pattern is found in the lowlands of Panama, with lower densities of rotifers and nematodes recorded in larger as compared to smaller bromeliads (Zotz & Traunspurger, 2016).…”

“…In French Guiana, protozoan richness increases with bromeliad water volume and their densities were positively associated with rotifer and macroinvertebrate densities (Carrias et al., ). A contrasting pattern is found in the lowlands of Panama, with lower densities of rotifers and nematodes recorded in larger as compared to smaller bromeliads (Zotz & Traunspurger, ). These results highlight the fact that taxonomic richness and relative densities of individual functional groups can differentially respond to environmental factors and indicate that these responses can be governed by local food web interactions (Srivastava & Bell, ).…”

The ability to get everywhere: dispersal modes of free-living, aquatic nematodes

“…They have also been collected from high-altitude lakes (up to 5,600 m above sea level) (Andrássy, 1978;Tsalolikhin, 2014), from deep-sea regions (down to 11,000 m below sea level) (Bik et al, 2010;Leduc & Rowden, 2018) and from caves and groundwater (Muschiol et al, 2015). In addition to these large-scale and permanent habitats, nematodes inhabit small, isolated and temporal environments, such as heat outlets or the volcanos of isolated islands (Muschiol & Traunspurger, 2009;Portnova, 2009;Schabetsberger et al, 2009;Portnova et al, 2011;Schabetsberger et al, 2013), ephemeral ponds with no connection to other waters or created by melt water or subject to sporadic desiccation and surrounded by desert or ice (Suren, 1990;Pinder et al, 2000;Chan et al, 2005), as well as water collections in plant components (phytotelmata) (Kitching, 2000;Ptatscheck et al, 2015a;Robaina et al, 2015;Zotz & Traunspurger, 2016).…”

“…In their study of 18 nematode species from the Galapagos Islands, Abebe & Coomans (1995) showed that 10 were cosmopolitan, 6 were at least common in the southern hemisphere and the remaining 2 were newly described species. For example, Rhabdolaimus terrestris de Man, 1880 was collected from the Galapagos Islands but also inhabits bromeliad phytotelmata in Panama as well as European, Ethiopian and Himalayan lakes and Vietnamese streams (Traunspurger, 1995;Gusakov et al, 2011;Ristau & Traunspurger, 2011;Schroeder et al, 2012;Tsalolikhin, 2014;Zotz & Traunspurger, 2016). Genetic studies have provided evidence of gene flow between metacommunities separated by hundreds of kilometers and therefore of the possible dispersal range of nematodes (Bik et al, 2010;Apolônio Silva de Oliveira et al, 2017; de Groote et al, 2017).…”

Copepods and ostracods associated with bromeliads in the Yucatán Peninsula, Mexico

“…Research interest in phytotelmata micro-environments has recently increased because such environments are considered living laboratories which enable study of different natural processes such as colonization, dispersal, predator-prey interaction and competition [ 9 ]. Studies of phytotelmata fauna, including tree cavities, puddles in stumps of bamboo and similar grasses, bromeliad tanks, pitcher plants, water filled coconut husks, and Heliconia flowers are typically dominated by larval stages of insects, yet several groups of invertebrates can also be found [ 10 , 11 ]. Among these invertebrates are freshwater crustaceans such as Ostracoda, Copepoda, and Anomopoda, which have been recognized as passive dispersers that move among habitat patches using other animals as vectors [ 10 , 12 , 13 ].…”