Study identifies new Gongylonema species in exotic mammals

A newly published study in Frontiers in Veterinary Science adds a new species to the Gongylonema genus and raises a fresh zoonotic flag for exotic animal medicine. Investigators described Gongylonema (G.) primatum sp. nov. from exotic mammals in the Czech Republic and separately identified zoonotic Gongylonema pulchrum in a Barbary macaque, marking the first report of that species in Macaca sylvanus. The paper was published July 8, 2026. (frontiersin.org)

The work builds on a limited but clinically relevant body of literature around Gongylonema, a group of spirurid nematodes that inhabit the upper digestive tract. G. pulchrum, often called the gullet worm, is already recognized as a veterinary parasite of mammals and birds, and CDC describes human infection as incidental and rare. Recent veterinary literature has also continued to document the parasite’s spread across wildlife hosts, including a 2024 Frontiers case report describing potentially zoonotic G. pulchrum in a free-living roe deer in Slovenia. (cdc.gov)

In the new study, the author examined a single female nematode from a dead Barbary macaque, along with 29 non-human primates from 13 species and two collared anteaters submitted for necropsy between 2019 and 2025 to the State Veterinary Institute Prague. Four primates, including two white-faced sakis, one white-lipped tamarin, and one Midas tamarin, plus both collared anteaters from the same zoological garden, were positive for the new species in the buccal cavity, tongue, and esophagus. The Barbary macaque specimen, from a different zoological garden, was identified as G. pulchrum. (frontiersin.org)

What makes the report more than a simple case series is the combined morphologic and molecular workup. The paper says G. primatum differed from related species by adult male body length, left spicule length, gubernaculum length, protruded vulvar lips, and the number of precloacal papillae. On sequencing, 18S and 28S rRNA genes were highly similar to G. nepalensis and G. pulchrum, but ITS and cox1 data showed lower similarity, supporting designation of a distinct species. The authors also note that, while G. pulchrum is clearly zoonotic, the new species may have zoonotic potential as well. (frontiersin.org)

Outside reaction specific to this paper appears limited so far, but the broader literature helps frame the significance. Merck Veterinary Manual notes that Gongylonema spp. use coprophagous insects, including beetles and cockroaches, as intermediate hosts, and that human infection is rare but linked to ingestion of infected insects, probably on vegetables. Reviews and human case reports consistently describe G. pulchrum as uncommon in people, difficult to recognize, and often presenting as a moving sensation in the oral cavity or upper digestive tract. A 2021 literature review said better clinician awareness could improve diagnosis and treatment, and CDC similarly notes that species-level identification is seldom confirmed. (merckvetmanual.com)

Why it matters: For zoo and exotic animal veterinarians, this study is a reminder that oral and esophageal parasites may be underdetected, especially when cases are identified only at necropsy or when animals die with nonspecific histories. The host range described here, spanning primates and anteaters in managed collections, suggests exposure pathways inside captive environments deserve scrutiny, particularly pest control, feed hygiene, enclosure sanitation, and possible access to insect intermediate hosts. For veterinary teams advising pet parents of exotic species or supporting public-facing collections, the detection of G. pulchrum in a primate adds another reason to take oral lesions, unexplained mucosal irritation, or unusual worms in the mouth or esophagus seriously. (frontiersin.org)

The study also matters diagnostically. Because 18S and 28S markers were very close to known species, the paper underscores why ITS and cox1 sequencing can be important when morphology alone leaves uncertainty. That’s relevant for referral labs, pathologists, and clinicians managing unusual nematodes in nontraditional hosts, where misclassification could blur both epidemiology and zoonotic risk assessments. (frontiersin.org)

What to watch: The next step is whether other groups confirm G. primatum in additional collections or free-ranging hosts, and whether future surveillance can show if this is a localized finding in Czech facilities or a wider, previously overlooked parasite of captive exotic mammals. (frontiersin.org)