Toxicocalamus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Subfamily: Hydrophiinae
Genus: Toxicocalamus
Boulenger, 1896

Toxicocalamus is a genus of snakes in the family Elapidae. The genus is endemic to New Guinea.[1]

Description

Most species of Toxicocalamus are relatively small, the largest specimen known being the holotype of the recently described Toxicocalamus ernstmayri, which measures 1.1 m (43 in) snout-to-vent length (SVL) and 1.2 m (47 in) in total length (TTL). The second longest is the holotype of T. grandis, which measures 0.88 m (35 in) SVL, 0.98 m (39 in) TTL. Most species are under 0.80 m (31 in) TTL, and several are the thickness of bootlaces. In general females have longer bodies than males, but much shorter tails.

Venom

Members of genus Toxicocalamus are venomous, with fixed front-fangs (a dental arrangement known as proteroglyphous), but are not known to be a threat to humans, being unaggressive, of modest size, and secretive. However, the venom of T. longissimus is believed to be fairly toxic, since it contains three-finger toxins (3FTx), Type-I phospholipase A2 (PLA2) and snake venom metalloproteinase (SVMP),[2] while T. buergersi possesses long venom glands than extend backwards into the body cavity.[1]

Behaviour

Although most species of Toxicocalamous are believed to be diurnal, they are fossorial, or semi-fossorial, in habit and rarely encountered.[3]

Geographic range

Many species of Toxicocalamus are localised in their distribution and associated with particular islands or mountain ranges. Several species are poorly known, with four known only from their holotypes. Toxicocalamus is probably not closely related to the Australian Elapidae, being endemic to the island of New Guinea, northern coastal offshore islands, i.e. Seleo Is. (Sandaun Province, PNG); Walis Is. and Tarawai Is. (East Sepik Province, PNG), and Karkar Is. (Madang Province, PNG), and the archipelagoes of Milne Bay Province to the southeast, i.e. d'Entrecasteaux Archipelago (Goodenough Is., Fergusson Is., and Normanby Is.), Woodlark Is., and the Louisiade Archipelago (Misima Is., Sudest Is., and Rossel Is.).[3][4][5]

Diet

The prey of snakes in the genus Toxicocalamus appears to consist almost entirely of earthworms, particularly the giant earthworms of the Megascolecidae,[5] hence the adoption of the term "worm-eating snakes" for species within this genus.

Reproduction

In common with other tropical elapids, Toxicocalamus is believed to reproduce by oviparity, with clutch sizes of 3–7 recorded, dependent on species and size of the female.

Natural history

The natural history of many species of Toxicocalamus is almost entirely undocumented, due to a paucity of specimens and the infrequence of their encounter in the field.

Species

The following 24 species, one of which has two subspecies, are currently recognised as being valid in the genus Toxicocalamus:[6]

  • Toxicocalamus preussi preussi (Sternfeld, 1913) [7] – Preuss's Sepek forest snake, Preuss' slender worm-eating snake
  • Toxicocalamus preussi angusticinctus Bogert & Matalas, 1945 [13] – Fly River forest snake, Fly River slender worm-eating snake

Nota bene: A binomial authority in parentheses indicates that the species was originally described in a genus other than Toxicocalamus. These former genera, Apistocalamus, Apisthocalamus, Pseudapistocalamus, Pseudapisthocalamus, Ultrocalamus, and Vanapina, are now synonyms of Toxicocalamus.

Taxonomy

The former species Pseudapisthocalamus nymani Lönnberg, 1900;[16] Apisthocalamus pratti Boulenger, 1904;[17] A. loennbergii Boulenger, 1908;[18] and A. lamingtoni Kinghorn, 1928;[19] are synonyms of T. loriae, Vanapina lineata De Vis, 1905 [20] is a synonym of T. longissimus,[21] and Ultrocalamus latisquamatus Schüz, 1929 [22] is a synonym of T. preussi.

Most of the described species are poorly known and rarely encountered. The most widely distributed, and most commonly encountered, species is T. loriae (itself a possible species complex), which accounts for 66% of all Toxicocalamus specimens in museum collections. T. loriae is frequently encountered in the Highlands, where large numbers have been collected in village gardens along the Wahgi River valley of Simbu Province, PNG. The next most frequently encountered and widely distributed species are T. preussi and T. stanleyanus. All the other species are much less well known and localised in distribution.

Also on mainland New Guinea, T. buergersi is known from only six specimens, from the Torricelli Mountains in the Sepik region (Sandaun and East Sepik Provinces), PNG; T. spilolepidotus is known from two specimens, from the Kratke Range, Eastern Highlands Province, PNG; T. pachysomus is known from its holotype, from the Cloudy Mountains, Milne Bay Province; PNG, T. cratermontanus from its holotype, from Crater Mountain, Simbu Province, PNG, while T. ernstmayri was only known from its holotype in the Star Mountains of Western Province, PNG, until a second specimen was observed crawling across mine-workings at the Ok Tedi Mine, in the Star Mountains.[23] Toxicocalamus grandis is also only known from its holotype, collected on the Setakwa River, western New Guinea, in 1912, (the only species represented by a type specimen west of the WNG/PNG border), and T. pumehanae is also only known from its holotype, from the Managalas Plateau, Oro Province, PNG,.

On the islands of Milne Bay, T. holopelturus is known from 19 specimens from Rossel Island, also known as Yela; T. misimae is known from six specimens from Misima Island; and T. mintoni is only known from its holotype, from Sudest Island, also known as Vanantai or Tagula Island, all in the Louisiade Archipelago. Toxicocalamus nigrescens is only known from its holotype and paratype, from Fergusson Island, in the d'Entercasteaux Archipelago, while T. longissimus is known from 12 specimens from Woodlark Island.

References

  1. ^ a b c d e McDowell, S.B. (1969). "Toxicocalamus, a New Guinea genus of snakes of the family Elapidae". Journal of Zoology, London. 159 (4): 443–511. doi:10.1111/j.1469-7998.1969.tb03900.x.
  2. ^ Calvete, J.J.; Ghezellou, P.; Paiva, O.; Matainaho, T.; Ghassempour, A.; Goudarzi, H.; Kraus, F.; Sanz, L.; Williams, D.J. (2012). "Snake venomics of two poorly known Hydrophiinae: Comparative proteomics of the venoms of terrestrial Toxicocalamus longissimus and marine Hydrophis cyanocinctus". Journal of Proteomics. 75 (13): 4091–4101. doi:10.1016/j.jprot.2012.05.026. PMID 22643073.
  3. ^ a b O'Shea, M. (1996). A Guide to the Snakes of Papua New Guinea. Port Moresby, Papua New Guinea: Independent Publishing. vii + 239 pp. ISBN 978-9810078362.. Link. January 1996. (22.2 MB)
  4. ^ Kraus, F. [in French] (2009). "New Species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea". Herpetologica. 65 (4): 460–467. doi:10.1655/09-002.1. S2CID 91287361.
  5. ^ a b c O'Shea, M.; Parker, F.; Kaiser, H. (2015). "A new species of New Guinea Worm-eating Snake, genus Toxicocalamus (Serpentes: Elapidae), from the Star Mountains of Western Province, Papua New Guinea, with a revised dichotomous key to the genus". Bulletin of the Museum of Comparative Zoology. 161 (6): 241–264. doi:10.3099/0027-4100-161.6.241. hdl:2436/621302.
  6. ^ Toxicocalamus at The Reptile Database
  7. ^ a b c Sternfeld, R (1913). "Beitrage zur Schlangenfauna Neuguineas und der benachbarten Inselgruppen ". Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin. 1913: 384–389. (in German).
  8. ^ Boulenger, G.A. (1914). "An Annotated List of the Batrachians and Reptiles collected by the British Ornithologists' Union Expedition and the Wollaston Expedition in Dutch New Guinea". Transactions of the Zoological Society of London. 20 (5): 247–274. doi:10.1111/j.1469-7998.1912.tb07833.x.
  9. ^ Boulenger, G.A. (1896). "Description of a new genus of elapine snakes from Woodlark Island, British New Guinea". Annals and Magazine of Natural History. 18 (104): 152. doi:10.1080/00222939608680426.
  10. ^ 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.
  11. ^ Kraus, Fred (2020-10-05). "A new species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea". Zootaxa. 4859 (1): 127–137. doi:10.11646/zootaxa.4859.1.5. ISSN 1175-5334. PMID 33056208. S2CID 222839671.
  12. ^ a b Kraus, F. (2009). "New species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea". Journal of Herpetology. 65 (4): 460–467. doi:10.1655/09-002.1. S2CID 91287361.
  13. ^ Bogert, C.M.; Matalas, B.L. (1945). "Results of the Archbold Expeditions. No. 53. A review of the elapid genus Ultrocalamus of New Guinea". American Museum Novitates (1284): 1–7.
  14. ^ O'Shea, M.; Allison, A. [in French]; 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 (4): 403–433. doi:10.1163/15685381-20181052. hdl:2436/621917. S2CID 91259224.
  15. ^ Boulenger, G.A. (1903). "Descriptions of new Reptiles from British New Guinea". Proceedings of the Zoological Society of London. 1903: 125–129.
  16. ^ Lönnberg, E. (1900). "Reptiles and amphibians collected in German New Guinea by the late Dr Erik Nyman". Annals and Magazine of Natural History. 3 (36): 574–582. doi:10.1080/00222930008678427.
  17. ^ Boulenger, G.A. (1904). "Descriptions of three new snakes". Annals and Magazine of Natural History. 13 (78): 450–452. doi:10.1080/00222930408562477.
  18. ^ Boulenger, G.A. (1908). "Description of a new elapine snake of the genus Apisthocalamus, Blg., from New Guinea". Annals and Magazine of Natural History. 1 (3): 248–249. doi:10.1080/00222930808692393.
  19. ^ Kinghorn, J.R. (1928). "Notes on some reptiles and batachians from the Northern Division of Papua, with descriptions of new species of Apisthocalamus and Lygosoma". Records of the Australian Museum. 16 (6): 289–293. doi:10.3853/j.0067-1975.16.1928.790.
  20. ^ De Vis, C.W. (1905). "A new genus of lizards". Annals of the Queensland Museum. 6: 46–52.
  21. ^ Ingram, G.J. [in French] (1989). "Vanapina lineata de Vis, 1905 is a junior synonym of the New Guinean snake Toxicocalamus longissimus Boulenger, 1896". Copeia. 1989 (3): 753–754. doi:10.2307/1445509. JSTOR 1445509.
  22. ^ Schüz, E. (1929). "Verzeichnis der Typen des Staatlichen Museums für Tierkunde in Dresden. Part 1. Fische, Amphibien und Reptilien mit einem Anhang: Die Schlangen der papuanischen Ausbeute Dr. Schlaginhäufen 1909". Abhandlungen und Berichte des Museum Tierkunde und Völkerkunde zu Dresden. 17: 14–16. (in German).
  23. ^ O'Shea, M.; Herlihy, B.; Paivu, B.; Parker, F.; Richards, S.J. [in French]; Kaiser, H. (2018). "Rediscovery of the rare Star Mountains Worm-eating Snake, Toxicocalamus ernstmayri O'Shea et al., 2015 (Serpentes: Elapidae: Hydrophiinae) with the description of its coloration in life". Amphibian and Reptile Conservation. 12 (1): 27–34.
Categories