Skip to main content Skip to main navigation menu Skip to site footer
Type: Article
Published: 2023-07-31
Page range: 41-51
Abstract views: 184
PDF downloaded: 3

Why Toxicocalamus longhagen Roberts, Iova & Austin, 2022 (Serpentes, Elapidae) is a taxonomic nomen dubium

Department of Ecology and Evolutionary Biology; University of Michigan; Ann Arbor; Michigan 48109; USA
Faculty of Science and Engineering; University of Wolverhampton; Wulfruna Street; Wolverhampton; West Midlands WV1 1LY; United Kingdom
Department of Biology; Victor Valley College; 18422 Bear Valley Road; Victorville; California 92395; USA; and Department of Vertebrate Zoology; Leibniz-Institut zur Analyse des Biodiversitätswandels; Zoologisches Forschungsmuseum Alexander Koenig; Adenauerallee 160; 53113 Bonn; Germany
Reptilia Code taxonomic status New Guinea nomenclature mihi itch worm-eating snake herpetology


Roberts et al. (2022) presented a taxonomic decision, in which they proposed the species name longhagen for a single, poorly preserved specimen of elapid New Guinean snake in the species assemblage known as the Toxicocalamus loriae Group. Geographically widespread populations in this species group had long been united under a single name even though some character variation had been noted, and only a thorough morphological study by Kraus et al. (2022), published shortly after the description of T. longhagen, confirmed additional species-level diversity and the detail of character analysis needed to differentiate species in this group. Their work made clear that only examination of many specimens would allow an assessment of interspecific variation and species boundaries, and this had been explained to the authors of the Roberts et al. paper ahead of their manuscript submission. The authors of the Kraus et al. paper had examined the specimen used to diagnose T. longhagen, as well as a series of similar specimens, and found it impossible to make a reliable species-level determination. Our detailed evaluation of the taxon longhagen reveals that it is insufficiently differentiated from the now-known species of the T. loriae Group, that it cannot confidently be assigned to any of these species, and that none of the existing specimens of snakes in this group can be assigned to T. longhagen. It follows that T. longhagen as currently defined is a taxonomic nomen dubium. It will retain this status until such time when additional data or additional material can lead to a resolution of its taxonomy.


  1. Anonymous [International Commission on Zoological Nomenclature] (1999) International code of zoological nomenclature. Fourth edition. London (The International Trust for Zoological Nomenclature): i–xxix + 1–306. <>.
  2. Boulenger, G. A. (1893) Catalogue of the snakes in the British Museum (Nat. Hist.). Volume 1. Containing the families Typhlopidæ, Glauconiidæ, Boidæ, Ilysiidæ, Uropeltidæ, Xenopeltidæ, and Colubridæ Aglyphæ, part. London (Taylor & Francis): i–xiii + 1–448. <>.
  3. Boulenger, G. A. (1898) An account of the Reptiles and Batrachians collected by Dr. L. Loria in British New Guinea. Annali del Museo civico di Storia naturale di Genova, (2), 18: 694–710.
  4. Boulenger, G. A. (1904) Descriptions of three new snakes. Annals and Magazine of natural History, (7), 13: 450–452. <>.
  5. Boulenger, G. A. (1908) Description of a new elapine snake of the genus Apisthocalamus, Blgr., from New Guinea. Annals and Magazine of natural History, (8), 1: 248–249. <>.
  6. Dubois, A. (2008) Le Code International de Nomenclature Zoologique: présentation, philosophie, règles majeures, problèmes actuels. In: D. Prat, A. Raynal-Roques & A. Roguenant (ed.), Peut-on classer le vivant? Linné et la systématique aujourd’hui, Paris (Éditions Belin): 355–402.
  7. Dubois, A. (2011) The International Code of Zoological Nomenclature must be drastically improved before it is too late. Bionomina, 2: 1–104. <>.
  8. Kaiser, H. (2013) The Taxon Filter, a novel mechanism designed to facilitate the relationship between taxonomy and nomenclature, vis-à-vis the utility of the Code’s Article 81 (the Commission’s plenary power). Bulletin of zoological Nomenclature, 70: 293–302. <>.
  9. Kaiser, H., Crother, B. I., Kelly, C. M. R., Luiselli, L., O’Shea, M., Ota, H., Passos, P., Schleip, W. D. & Wüster, W. (2013) Best practices: in the 21st century, taxonomic decisions in herpetology are acceptable only when supported by a body of evidence and published via peer-review. Herpetological Review, 44: 8–23.
  10. Kinghorn, J. R. (1928) Notes on some reptiles and batrachians from the Northern Division of Papua, with descriptions of new species of Apisthocalamus and Lygosoma. Records of the Australian Museum, 16: 289–293. <>.
  11. Kraus, F. (2009) New species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea. Herpetologica, 65: 460–467. <>.
  12. Kraus, F. (2017) Two new species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea. Journal of Herpetology, 51: 574–581. <>.
  13. Kraus, F. (2020) A new species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea. Zootaxa, 4859: 127–137. <>.
  14. Kraus, F., Kaiser, H. & O’Shea, M. (2022) Hidden diversity in semi-fossorial Melanesian forest snakes: a revision of the Toxicocalamus loriae complex (Squamata, Elapidae) from New Guinea. Vertebrate Zoology, 72: 997–1034. <>.
  15. Lillywhite, H. B. (2008) Dictionary of herpetology. Malabar (Krieger): 1–384.
  16. Lönnberg, E. (1900) Reptiles and batrachians collected in German New Guinea by the late Dr Erik Nyman. Annals and Magazine of natural History, (7), 6: 574–582. <>.
  17. Malnate, E. V. & Underwood, G. (1988) Australasian natricine snakes of the genus Tropidonophis. Proceedings of the Academy of natural Sciences of Philadelphia, 140: 59–201
  18. Mayr, E. (1969) Principles of systematic zoology. New York (McGraw Hill): i–xi + 1–428.
  19. McDowell, S. B. (1967) Aspidomorphus, a genus of New Guinea snakes of the family Elapidae, with notes on related genera. Journal of Zoology, London, 151: 497–543. <>.
  20. McDowell, S. B. (1969) Toxicocalamus, a New Guinea genus of snakes of the family Elapidae. Journal of Zoology, London, 159: 443–511. <>.
  21. Mones, A. (1989) Nomen dubium vs. nomen vanum. Journal of Vertebrate Paleontology, 9: 232–234. <>.
  22. O’Shea, M., Allison, A. & Kaiser, H. (2018) The taxonomic history of the enigmatic Papuan snake genus Toxicocalamus (Elapidae: Hydrophiinae), with the description of a new species from the Managalas Plateau of Oro Province, Papua New Guinea, and a revised dichotomous key. Amphibia-Reptilia, 39: 403–433. <>.
  23. Peters, J. A. (1964) Dictionary of herpetology. A brief and meaningful definition of words and terms used in herpetology. New York (Hafner Publishing): 1–392.
  24. Roberts, J. R. & Austin, C. C. (2020) A new species of New Guinea worm-eating snake (Elapidae: Toxicocalamus Boulenger, 1896), with comments on postfrontal bone variation based on micro-computed tomography. Journal of Herpetology, 54: 446–459. <>.
  25. Roberts, J. R., Iova, B. & Austin, C. C. (2022) A new species of New Guinea worm-eating snake (Serpentes, Elapidae, Toxicocalamus Boulenger, 1896) from Western Highlands Province, Papua New Guinea. Zoosystematics and Evolution, 98: 399–409. <>.
  26. Strickland, J. L., Carter, S., Kraus, F. & Parkinson, C. (2016) Snake evolution in Melanesia: origin of the Hydrophiinae (Serpentes, Elapidae) and the evolutionary history of the enigmatic New Guinean elapid Toxicocalamus. Zoological Journal of the Linnean Society, 178: 663–678. .