Petroglyph logo Petroglyph logo
Home     Contact us     Search     Who we are
     General Information    Research    Literature    Databases    Images


   Research Aims
      Overall objectives
   Current Research
   Research Publications

Research -> Research Aims


The phylum Nematomorpha is one of approximately 35 animal phyla. Nematomorphs are obligate parasites of arthropod hosts but are free-living in aquatic environments as adults. Gordiids, or freshwater nematomorphs, can be up to 3m long and suddenly seem to appear in domestic sources of water (swimming pools, toilets, pet bowls). Human encounters interactions with these worms are quite common, often leading to numerous unnecessary trips to the doctors or veterinarians. About 300 species of nematomorphs have been described worldwide, but we estimate that there may be as many as 1,900 species globally. At the current rate of taxonomy, it would take over 500 years to describe the remaining species within this relatively small group.

Our current project will reinvestigate the members of the Gordiida, with specific focus on the fauna in Central and South America. New World gordiids have been well documented from North America and Argentina, but outside of these immediate areas, few records are known from this species rich area. Recent reviews of the gordiid fauna from South and Central America suggest that many species are only known from isolated records but that the species diversity is extremely rich. Study of gordiids in the Americas will allow us to investigate a gradient on a continuous landmass, from moderate regions in the United States, to tropical areas in South America, and to investigate the impact of continental separation and subsequent faunal exchange through Central America. This project will use both traditional and a revolutionary sample collection, site and species identification technique, allowing us to overcome obstacles hampering previous large-scale investigations.

Our research objectives

To a) catalog the phylum Nematomorpha with a current emphasis on Central and South America, b)produce modern descriptive treaties of all nematomorph genera, c) create a stable classification of nematomorphs using molecular tools, d) train young scientists to become proficient at field work and modern techniques allowing them to become the next generation of biodiversity pioneers, e) educate the public about gordiids and make available information about their life cycle and harmlessness, f) create an on-line environment providing all aspects of nematomorph species, and ensure that this database is permanent.

Our overall goals

This work will result in the generation of a global phylogeny of one animal phylum; a phylum whose taxa are in taxonomic chaos. For example, taxa above the genus-level have not been established. This phylogeny will aid the future studies of interesting ecological interactions of nematomorphs including their historical biogeography and host use. We will be training 1 postdoctoral fellow, 3 graduate students, and at least 6 undergraduate students through workshops, and mini-symposia which will be held in concert with the annual meeting of the American Society of Parasitologists. Students will participate in all activities of the grant (filed collecting, data processing and analysis, etc).

Impacts of this project

This project is an internationally-collaborative project involving several US universities and universities from around the world. We will advance the understanding of nematomorphs and parasites by providing web pages targeted at lay people, but especially children, and by producing several high-school and above introductory biology laboratory exercises, which will be published in a workshop manual, and will be available for download. The University of New Mexico is designated a Minority-Serving Institution, and we heavily recruit and involve students and researchers from underrepresented groups. Our findings will be widely disseminated by a) annual scientific meetings, b) publishing in peer-reviewed journals, c) working with research teams and collaborators in at least 8 countries, d) launching this website with links to information targeted at the general public and providing access to our databases.


We are currently involved in collecting specimens from around the world.  Over the last year, we have collected several new species from Africa.  Two of these species have been successfully reared in the laboratory and are being used as model systems to study host-parasite interactions.

Over the past years, we have also collected new species from the United States and Costa Rica.  In addition, scientists from around the world are sending us new specimens; several of these are likely to represent new species.  We have received specimens from places such as Taiwan, New Zealand, Nicaragua, and Malaysia.


Copyright 2014 Ben Hanelt, Matt Bolek, and Andreas Schmidt-Rhaesa
Updated: July 2015