Abstract
Two species of Bush Vipers, genus Atheris Cope, 1862, have been reported for the continental island of Bioko, Gulf of Guinea – Atheris squamigera and a putatively undescribed species, morphologically similar to Atheris chlorechis. The latter was only known from one specimen collected in the early 1900s and its taxonomic identity has never been fully resolved. Based on recently collected specimens of Atheris from Bioko Island, we reviewed all the available data and specimens through detailed morphological comparisons against all known species of the genus. Our results confirm that Atheris squamigera is present in Bioko Island, and that the second taxon is a new species, which we describe here as Atheris hetfieldi sp. nov. The newly described species presents a series of morphological characters that clearly differentiate it from all of its congeners. The description of this new species is the first of a new snake species from Bioko in more than 100 years and this species is the only snake currently recognized as endemic to the island.
References
Ashe, J. (1968) A new bush viper. Journal of the East Africa Natural History Society and National Museum, 27 (1), 53–59.
Bocage, J.V.B. (1895) Subsidios para a fauna da ilha de Fernão do Pó. Jornal das Sciencias Mathematicas, Physicas e Naturaes, Segunda Série, 9, 13–12.
Bocage, J.V.B. (1903) Contribution à la Faune des quatre îles du golfe de Guinée. Jornal das Sciencias Mathematicas, Physicas e Naturaes, Segunda Série, 7, 25–59.
Bogert, C.M. (1940) Herpetological results of the Vernay Angola Expedition. I. Snakes, including an arrangement of the African Colubridae. Bulletin of the American Museum of Natural History, 77, 1–107.
Boulenger, G.A. (1906) Report on the reptiles collected by the late L. Fea in West Africa. Annali del Museo Civico di Storia Naturale di Genova, 3 (2), 196–216.
Branch, W.R. & Bayliss, J. (2009) A new species of Atheris (Serpentes: Viperidae) from northern Mozambique. Zootaxa, 2113 (1), 41–54.
https://doi.org/10.11646/zootaxa.2113.1.2
Broadley, D.G. (1998) A review of the genus Atheris Cope (Serpentes: Viperidae), with the description of a new species from Uganda. The Herpetological Journal, 8, 117–135.
Capocaccia, L. (1961) Contributo allo studio dei serpenti delle isole del Golfo di Guinea. Annali del Museo Civico di Storia Naturale “Giacomo Doria”, 72, 285–309.
Ceríaco, L.M.P. (2015) Lost in the middle of the sea, found in the back of the shelf: A new giant species of Trachylepis (Squamata: Scincidae) from Tinhosa Grande islet, Gulf of Guinea. Zootaxa, 3973 (3), 511–527.
https://doi.org/10.11646/zootaxa.3973.3.6
Ceríaco, L.M.P., Marques, M.P. & Bauer, A.M. (2016) A review of the genus Trachylepis (Sauria: Scincidae) from the Gulf of Guinea, with descriptions of two new species in the Trachylepis maculilabris (Gray, 1845) species complex. Zootaxa, 4109 (3), 284–314.
https://doi.org/10.11646/zootaxa.4109.3.2
Ceríaco, L.M.P., Marques, M.P., Schmitz, A. & Bauer, A.M. (2017) The “Cobra-preta” of São Tomé Island, Gulf of Guinea, is a new species of Naja Laurenti, 1768 (Squamata: Elapidae). Zootaxa, 4324 (1), 121–141.
https://doi.org/10.11646/zootaxa.4324.1.7
Ceríaco, L.M.P., Marques, M.P. & Bauer, A.M. (2018) Miscellanea Herpetologica Sanctithomae, with a provisional checklist of the terrestrial herpetofauna of São Tomé, Príncipe and Annobon islands. Zootaxa, 4387 (1), 91–108.
https://doi.org/10.11646/zootaxa.4387.1.4
Chippaux, J.-P. & Jackson, K. (2019) Snakes of Central and Western Africa. Johns Hopkins University Press, Baltimore, Maryland, 448 pp.
Collet, M. & Trape, J.-F. (2020) Une nouvelle espèce du genre Atheris Cope, 1862, de la province de l’Équateur en République Démocratique du Congo (Squamata: Viperidae). Bulletin de la Société Herpétologique de France, 173, 27–40.
Cope, E.D. (1862) Notes upon some reptiles of the Old World. Proceedings of the Academy of Natural Science of Philadelphia, 14, 337–344.
de Witte, G.F. (1953) Reptiles. Exploration du Parc National de l’Upemba. Mission G. F. de Witte en collaboration avec W. Adam, A. Janssens, L. Van Meel et R. Verheyen (1946–1949). Institut des Parcs Nationaux du Congo Belge, Brussels, 6, 1–322.
Dobiey, M. & Vogel, G. (2007) Venomous Snakes of Africa/Giftschalangen Afrikas. Terralog 15. Edition Chimaira, Frankfurt am Main, 150 pp.
Eisentraut, M. (1973) Die Wirbeltierfauna von Fernando Poo und Westkamerun. Unter besonderer Berücksichtigung der Bedeutung der pleistozänen Klimaschwankungen für die heutige Faunenverteilung. Bonner Zoologische Monographien, 3, 1–428, pls. 1–5.
Ernst, R. & Rödel, M.O. (2002) A new Atheris species (Serpentes: Viperidae), from Taï National Park, Ivory Coast. The Herpetological Journal, 12, 55–61.
Fischer, J.G. (1888) Über zwei neue Schlangen und einen neuen Laubfrosch von Kamerun. Jahrbuch der Hamburgischen Wissenschaftlichen Anstalten, 5, 1–10.
Hallowell, E. (“1854” 1855) Descriptions of new reptiles from Guinea. Proceedings of the Academy of Natural Science of Philadelphia, 7, 193–194.
IUCN (2001) IUCN Red List Categories and Criteria. Version 3.1. 2nd Edition. IUCN, Gland and Cambridge, iv + 32 pp.
Jones, P.J. (1994) Biodiversity in the Gulf of Guinea: an overview. Biodiversity and Conservation, 3, 772–784.
https://doi.org/10.1007/BF00129657
Laurent, R.F. (1955) Diagnoses préliminaires des quelques serpents venimeux. Revue de zoologie et de botanique africaines, 51, 127–139.
Lawson, D.P. (1999) A new species of arboreal viper (Serpentes: Viperidae: Atheris) from Cameroon, Africa. Proceedings of the Biological Society of Washington, 112 (4), 793–803.
Loveridge, A. (1930) Preliminary description of a new tree viper of the genus Atheris from Tanganyika Territory. Proceedings of the New England Zoological Club, 11, 107–108.
Martin, W. (1838) On some species of chameleon from Fernando Póo. Proceedings of the Zoological Society of London, 1838, 63–65.
Martinez Y Saez, F.P. (1866) Enumeración y estudio de las coleciones recogidas en su viaje por el Dr Ossorio. Vertebrados. Anales de la Sociedad Española de Historia Natural, 15, 339.
Menegon, M., Davenport, T.R.B. & Howell, K.M. (2011) Description of a new and critically endangered species of Atheris (Serpentes: Viperidae) from the Southern Highlands of Tanzania, with an overview of the country’s tree viper fauna. Zootaxa, 3120 (1), 43–54.
https://doi.org/10.11646/zootaxa.3120.1.3
Menegon, M., Loader, S.P., Marsden, S.J., Branch, W.R., Davenport, T.R.B. & Ursenbacher, S. (2014) The genus Atheris (Serpentes: Viperidae) in East Africa: Phylogeny and the role of rifting and climate in shaping the current pattern of species diversity. Molecular Phylogenetics and Evolution, 79, 12–22.
https://doi.org/10.1016/j.ympev.2014.06.007
Mertens, R. (1941) Zur Kenntnis der Herpetofauna von Fernando Póo. Zoologischer Anzeiger, 135, 275–281.
Mertens, R. (1964) Die Reptilien von Fernando Póo. Bonner Zoologische Beiträge, 15, 211–238.
Mertens, R. (1966) Zwei Nachträge zu: “Die Reptilien von Fernando Póo”. Bonner Zoologische Beiträge, 17 (1/2), 52.
Mertens, R. (1968) Zur Kenntnis der Herpetofauna von Kamerun und Fernando Póo. Bonner Zoologische Beiträge, 19, 69–84.
Miller, E.C., Sellas, A.B. & Drewes, R.C. (2012) A new species of Hemidactylus (Squamata: Gekkonidae) from Príncipe Island, Gulf of Guinea, West Africa with comments on the African-Atlantic clade of Hemidactylus geckos. African Journal of Herpetology, 61 (1), 40–57.
https://doi.org/10.1080/21564574.2012.666680
Mocquard, M.F. (1887) Sur les ophidiens rapportés du Congo par la Mission de Brazza. Bulletin de la Socieìteì philomathique de Paris, 11 (7), 62–92.
Pel, H.S. (1852) Over de jagt aan de Goudkust, volgens eene tienjarige eigene ondervinding. Ned. Tijdschr. Jagtkunde, 1, 149–173.
Penner, J., Nono, G.L. & & Rödel, M.O. (2013) Second record of the West African hairy bush viper Atheris hirsuta Ersnt & Rödel, 2002 (Serpentes: Viperidae). Zootaxa, 3694 (2), 196–200.
https://doi.org/10.11646/zootaxa.3694.2.9
Phelps, T. (2010) Old World Vipers. Edition Chimaira, Frankfurt am Main, 558 pp.
Spawls, S. & Branch, W.R. (2020) The Dangerous Snakes of Africa. Bloomsbury Wildlife, London, 336 pp.
Soares, L.B., Ceríaco, L.M.P., Marques, M.P., Bastos-Silveira, C., Scheinberg, L.A., Harris, D.J., Brehm, A. & Jesus, J. (2018) Review of the leaf-litter skinks (Scincidae: Panaspis) from the Gulf of Guinea oceanic islands, with the description of a new species. African Journal of Herpetology, 67 (2), 132–159.
https://doi.org/10.1080/21564574.2017.1413015
Tornier, G. (1902) Herpetologisch Neues aus Deutsch-Ostafrika. Zoologische Jahrbücher, 15, 578–590.
https://doi.org/10.5962/bhl.part.19041
Trape, J.-F. & Mané, Y. (2006) Guide des serpents d’Afrique occidentale. Savane et désert. IRD Editions, Paris, 226 pp.
Uetz, P., Freed, P. & Hošek, J. (Eds.) (2020) The Reptile Database. Available from: http://www.reptile-database.org (accessed 28 April 2020)
Valente, L.M., Etienne, R.S. & Phillimore, A.B. (2014) The effects of islands ontogeny on species diversity and phylogeny. Proceedings of the Royal Society B, Biological Sciences, 281 (1784). [published online]
https://doi.org/10.1098/rspb.2013.3227
Valente, L., Phillimore, A.B., Melo, M., Warren, B.H., Clegg, S.M., Havenstein, K., Tiedemann, R., Illera, J.C., Thébaud, C., Aschenbach, T. & Etienne, R.S. (2020) A simple dynamic model explains the diversity of island birds worldwide. Nature, 579, 921–96.
https://doi.org/10.1038/s41586-020-2022-5
Veron, S., Haevermans, T., Govaerts, R., Mouchet, M. & Pellens, R. (2019) Distribution and relative age of endemism across islands worldwide. Scientifc Reports, 9, 11693.
https://doi.org/10.1038/s41598-019-47951-6
Wagner, P., Leaché, A. & Fujita, M.K. (2014) Description of four new West African forest geckos of the Hemidactylus fasciatus Gray, 1842 complex, revealed by coalescent species delimitation. Bonn Zoological Bulletin, 63 (1), 1–14.
Wallach, V., Kenneth, I.W. & Boundy, J. (2014) Snakes of the World: A Catalogue of Living and Extinct Species. CRC Press, Boca Raton, Florida, xxvi + [2] + 1209 pp.
Werner, F. (1896 [1895]) Über einige Reptilien aus Usambara (Deutsch-Ostafrika). Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien, 45, 190–194.
https://doi.org/10.5962/bhl.part.26910