Ophiophagus Günther, 1864

Das, Indraneil, Shankar, P. Gowri, Swamy, Priyanka, Williams, Rhiannon C., Lalremsanga, Hmar Tlawmte, Prashanth, P., Sahoo, Gunanidhi, Vijayakumar, S. P., Höglund, Jacob, Shanker, Kartik, Dutta, Sushil K., Ganesh, S. R. & Wüster, Wolfgang, 2024, Taxonomic revision of the king cobra Ophiophagus hannah (Cantor, 1836) species complex (Reptilia: Serpentes: Elapidae), with the description of two new species, European Journal of Taxonomy 961 (1), pp. 1-51 : 8-11

Genus Ophiophagus Günther, 1864

Hoplocephalus Wagler, 1830: 342 (in prevailing usage for Australian Broad-headed snakes).

Hamadryas Cantor, 1836: 187 (preoccupied; by Hamadryas Hübner, 1818 ).

Dendraspis Fitzinger, 1843: 28 (suppressed; for Dendroaspis Schlegel, 1848 ).

Ophiophagus Günther, 1864: 340 . Official Generic Name No. 1599 Opinion 709 ( ICZN 1964).

Type species

Hamadryas elaps Günther, 1858 fide Opinion 709 of ICZN (1964: 210).

Etymology

Greek, alluding to the snake-eating habits of member(s) of the genus, from the respective roots, ‘ ophis ’ for ‘snake’ and ‘ phagos ’ for ‘eater’.

Nomenclatural remarks

The nomenclature of the generic name of the king cobra has been subject to considerable confusion. The original generic nomen, Hamadryas Cantor, 1836 was identified as preoccupied by Hamadryas Hübner, 1818 ( Insecta: Lepidoptera ) (see Bogert 1945; ICZN 1964; Smith & Chiszar 1989). Zhao & Adler (1993: 271) mentioned that Hübner (1806), usually cited as the source of the generic name, only used the plural form Hamadryades . The next oldest generic name, Dendraspis Fitzinger, 1843 , was suppressed ( ICZN 1964), due the likelihood of confusion with the genus Dendroaspis Schlegel, 1848 .

Günther (1864: 340) established the genus Ophiophagus , with Hamadryas elaps Günther, 1858 as the sole included species, and hence the type species by monotypy. The specific epithet elaps has a confused history. Günther (1858, 1864) had erroneously attributed the name elaps to Lesson, 1829, as well as to Schlegel, 1837. In fact, Lesson did not use the specific epithet elaps , but instead described Coluber ikaheca Lesson, 1830 (now Micropechis ikaheca ). The name Naja elaps was thus newly established by Schlegel (1837). The clear description and illustration in Schlegel (1844) leave no doubt that Naja elaps is a junior synonym of Lesson’s Coluber ikaheca (see Mertens 1962). However, despite attributing the name elaps to Schlegel, in listing Hamadryas elaps, Günther (1858) provided an unmistakable description of the king cobra: the ventral and subcaudal scale counts lie outside the ranges for Micropechis Boulenger, 1896 , the mixed single and divided subcaudals, a clear description of what are now called the occipital scales (the term ‘occipital scales’ was used by Günther and his contemporaries for what are now termed the parietal scales) and the size of the species are unambiguously characteristic of the king cobra. Günther’s synonymy and chresonymy make clear that O. elaps is a chresonym of Hamadryas elaps Günther, 1858 . The inclusion of Naja elaps Schlegel, 1837 in the synonymy of O. elaps is most probably a mistake of Günther, either a lapsus or a confusion with Naja bungarus , a taxon that is indeed a king cobra.

Mertens (1962) asked the ICZN to designate “ Hamadryas elaps Günther, 1858 [equivalent to hannah Cantor, 1836 ]” as the type species of Ophiophagus . This was enacted by Opinion 709 of ICZN (1964: 210), fixing Hamadryas elaps Günther, 1858 as the type species of the genus Ophiophagus Günther, 1864 .

While the nomenclature of the genus has been stable in the literature since ICZN Opinion 709 ( ICZN 1964), several problematic issues have remained overlooked. Boie (1828a, 1828b) used the nomen Naja bungaroides for a juvenile (RMNH 1334; see below) from Java. We treat it as a nomen nudum, as the description, “due to the makeup of the scuta subcaudalia”, does not constitute a “description or definition”, as required by Article 12.1 of the Code ( ICZN 1999) and defined in the Glossary therein ( Mees 1957; David & Ineich 1999). Wagler (1830: 342) cited Boie’s Naja bungaroidea (incorrect subsequent spelling of Naja bungaroides ) and provided a diagnosis sufficient to make the name available. In the same publication, Wagler also proposed a new genus, Hoplocephalus , for Naja bungaroides . The consequence of this, overlooked ever since, is that the type species of the genus Hoplocephalus is Naja bungaroides Wagler, 1830 , a king cobra, not the Australian broad-headed snake which Schlegel (1837) named Naja bungaroides (while also creating the name Naja bungarus for Boie’s species). Schlegel’s name bungaroides has been consistently applied to the Australian species since, while it is Schlegel’s Naja bungarus that has long been associated with Ophiophagus . A strict interpretation of the Code would make Hoplocephalus the oldest available genus-group name for the king cobra, and bungaroides the oldest species-group name for any king cobra species. This would upend the nomenclature of two culturally iconic, medically important and IUCN Red-Listed genera of elapid snakes, each with a large associated body of literature.

A Case to the International Commission of Zoological Nomenclature is in preparation to preserve the prevailing usage of the genus-group names Ophiophagus and Hoplocephalus and of the binomen Hoplocephalus bungaroides . This will require setting aside the type of Wagler’s Naja bungaroides and the designation of a neotype belonging to the Australian broad-headed snake. The action will make Wagler’s name unavailable for any king cobra. In anticipation of a Commission Opinion in favour of this case, we have therefore refrained from using Wagler’s name bungaroides for any king cobra species, and have used the next-oldest available name in all cases. In the interest of nomenclatural stability, all affected nomina should continue to be used in the prevailing manner pending resolution of the case by the Commission.

Nomenclatural histories of species-series nomina

The type species of Ophiophagus , Cantor’s (1836) Hamadryas hannah , was from “Sunderbuns”, equivalent to the Sunderbans of Bengal, a large deltaic region of mangrove forests at the confluence of the rivers Ganga, Brahmaputra and Padma, covering an area of ca 10 000 sq km in modern day India and Bangladesh, and “jungle not far from Calcutta” (since 2001, Kolkata, the administrative capital of West Bengal State, eastern India), located ca 56 km NW of the Sunderbans. It is unclear where the four syntypes were deposited and these are considered not extant at present ( Toriba 1993). Several other snake types of Cantor are unlocated, and a few are preserved either as specimens in the BMNH or depicted in numbered, coloured plates in the Bodleian Library of Oxford University, Oxford, United Kingdom. The original description, published in Asiatick Researches (later modified to ‘ Asiatic Researches ’, its full form, ‘ Transactions of the Society Instituted in Bengal for Inquiring into the History and Antiquities, the Arts, Sciences and Literature of Asia ’), which was a short-lived (1798–1836) journal published by the Asiatic Society of Bengal from Calcutta. The original description contained a nine-line Latin diagnosis of the purported new genus Hamadryas Cantor, 1836 , and a two-line diagnosis of the species, followed by five pages of description and reports on its behaviour, as reported by local inhabitants of the region. Three plates accompany the description, the first showing the head with neck expanded in anterior and posterior views ( Cantor 1836: fig. 1), the second showing the cranium and mandible as well as dissected head showing cranial muscles as well as the venom glands ( Cantor 1836: fig. 2), and finally, the head in dorsal and ventral views, showing close-ups of some scales and the posterior venter and tail, showing ventral and subcaudal scales ( Cantor 1836: fig. 3).

About two years later, Cantor’s (1838) redescription of the same species, as Hamadryas ophiophagus , was read out at the 12 June 1838 meeting of the Zoological Society of London, a somewhat rare case of synonymy involving the same author. The rationale for the action remains unknown, because Cantor (1838) alludes to his 1836 paper, and may either be on account of Cantor’s desire to disseminate the information regarding his remarkable new species to a scholarly audience at home, and his realization of the transient nature of the Asiatic Researches.

Several names have been applied to members of the genus. The taxonomic and nomenclatural history is elaborated below. The nomina currently recognised as synonyms include Naja bungarus Schlegel, 1837 ; Hamadryas ophiophagus Cantor, 1838 ; Naia vittata Elliot, 1840 ; Dimeresurus boiei Bleeker, 1858 (a nomen nudum, carrying no description; the name [in the combination Trimeresurus boiei ] was synonymised with Naia bungarus Schlegel, 1837 by Boulenger 1896: 396); and Naja ingens A.W.M. van Hasselt, 1858 (although Smith 1943 and Toriba 1993, incorrectly attributed this name to van Hasselt 1882).

In his review of the king cobra species complex (which he assigned to the genus Dendraspis Fitzinger, 1843 ), Deraniyagala (1960) established two new taxa, D. hannah sinensis (for the Chinese population) and D. h. borneensis (for the Bornean population), while also reviving the following names as subspecies: vittata ( Elliot, 1840) for the south-western Indian population, and bungarus Schlegel, 1837 , for the Sumatran population. In a subsequent paper, Deraniyagala (1961) described two further subspecies, D. hannah nordicus (from Mamgain, Dunda Lakhond, Dehra Dun, India and apparently also eastern Pakistan) and D. hannah brunnea (from the vicinity of Darjeeling, India).

The holotype of Cantor’s (1836) Hamadryas hannah is erroneously mentioned as BMNH 1996.461 (ex RSL) by Wallach et al. (2014) and Leviton et al. (2018); this is instead the holotype of Elliot’s (1840) Naia vittata , a subjective junior synonym of Ophiophagus hannah , a stuffed specimen, presumably once a ‘gallery’ specimen, which was rediscovered uncatalogued in the basement of the London collection during the course of this research in 1996. BMNH 1996.461 (ex RSL) appears to have been examined by Günther (1858) and Boulenger (1896), who list it in their respective catalogues.

The first use of the current combination for the nominate species, Ophiophagus hannah , is by Bogert (1945). A near complete synonymy for the Sunda region has been provided by David & Vogel (1996), and synonyms for populations from the Asian mainland have been listed in Smith (1943), Taylor (1965) and Zhao & Adler (1993). Leviton (1968) provided the most exhaustive chresonymy for Ophiophagus hannah .

Of the nine nomenclaturally valid nomina ( Cantor 1836; Schlegel 1837; Cantor 1838; Elliot 1840; van Hasselt 1858; Deraniyagala 1960, 1961) that are currently allocated to Opiophagus sensu Günther, 1864, two ( Hamadryas hannah ; Naja bungarus ) are shown in this paper to represent taxonomically valid species. An additional two populations, from the Western Ghats ( India) and the island of Luzon (the Philippines) are described as new to science (see also Gowri Shankar et al. 2021).

Content

Four species, corresponding to the four Confirmed Candidate Species, CCS (sensu Padial et al. 2010) of Gowri Shankar et al. (2021):

Ophiophagus hannah s. str.: a widespread Asian mainland lineage, distributed from eastern Pakistan, northern and eastern India east to China and south to Myanmar, northern and central Thailand, Cambodia, Laos, Vietnam, as well as on the Andaman Islands. CCS2 of Gowri Shankar et al. (2021).

A Sundaland species from the Malay Peninsula, and islands of the Greater Sundas, including Sumatra, Borneo and Java, in addition to Mindoro (in the Philippines). CCS3 of Gowri Shankar et al. (2021). The nomen Naja bungarus originating from West Java, is the oldest available one for this form (read below).

A geographically isolated, unnamed species from the Western Ghats of south-western India. CCS1 of Gowri Shankar et al. (2021).

A second unnamed species, representing an isolated lineage from the island of Luzon (in the Philippines). CCS4 of Gowri Shankar et al. (2021).