Acanthophis lancasteri Wells & Wellington, 1985

Ellis, Ryan J., Kaiser, Hinrich, Maddock, Simon T., Doughty, Paul & Wüster, Wolfgang, 2021, An evaluation of the nomina for death adders (Acanthophis Daudin, 1803) proposed by Wells & Wellington (1985), and confirmation of A. cryptamydros Maddock et al., 2015 as the valid name for the Kimberley death adder, Zootaxa 4995 (1), pp. 161-172 : 163-166

Availability of Acanthophis lancasteri Wells & Wellington, 1985

Wells & Wellington’s description. The entire account (including diagnosis and description) of Acanthophis lancasteri was published as follows, reproduced here as in the original, including errors in spelling and punctuation ( Wells & Wellington 1985: 43–44):

“ Acanthophis lancasteri sp.nov.

Holotype: An adult specimen in the Western Australian Museum R 70690. Collected at 45 km NNE of Halls Creek, Western Australia.

Diagnosis: A member of the Acanthophis antarcticus complex, most closely related to Acanthophis praelongus , and readily identified by the description in Storr (1981:209-210) the material utilised by Storr, excluding those specimens from the Northern Territory, is referable to Acanthophis lancasteri , rather than A. praelongus ). Acanthophis lancasteri is believed confined to northwestern Australia and across the ‘Top End’ of the Northern Territory. Acanthophis praelongus is believed confined to Cape York, Peninsula Queensland. Excellent diagnostic illustrations of Acanthophis lancasteri appear in Storr (1981: Fig.4), Cogger (1983: Plate 764 - cited as ‘ Acanthophis praelongus ’), in Gow (1977: Plate 22 - cited as ‘ Acanthophis antarcticus ’) and in Gow (1982: Plate 3 - cited as ‘ Acanthophis praelongus ’). Etymology: Named for actor and philosopher Burt Lancaster.”

Apart from clearly failing to conform to Recommendation 13A, the description of A. lancasteri provided no statement of characters purported to differentiate the species. The references to “diagnostic illustrations” do not furnish “a description or definition that states in words characters that are purported to differentiate the taxon” (Article 13.1.1.). Consequently, the availability of the nomen A. lancasteri hinges solely on Storr (1981) and its conformity with Articles 13.1.1. and 13.1.2.

Storr’s “taxon” and incomplete diagnosis. There are two reasons why Storr’s (1981) diagnoses are insufficient to make A. lancasteri available. The first is that Storr recognised three species of Acanthophis in WA, based on specimens housed at the Western Australian Museum (WAM): A. antarcticus ( Shaw & Nodder, 1802) , A. pyrrhus Boulenger, 1898 , and A. praelongus Ramsay, 1877 . Storr’s (1981) concept of A. praelongus included the type specimen of A. praelongus from Cape York, Queensland, as well as the subspecies A. antarcticus rugosus Loveridge, 1948 , whose type specimen is from New Guinea and which is listed in the synonymy of A. praelongus in Storr’s account. Storr’s morphological description was based on material from the Kimberley Region of WA and from the NT, but he did not in any way intend (“purport” in the words of the Code) to diagnose the Kimberley population from other A. praelongus . His “Key to Western Australian Species” unambiguously sought to differentiate what he considered A. antarcticus , A. pyrrhus , and A. praelongus , but without any indication that the use of the key was restricted to WA, or that the WA populations of any of these species should be considered distinct from populations elsewhere. Nowhere did Storr diagnose or suggest the existence of “ Acanthophis praelongus sensu Storr 1981 nec Ramsay, 1877,” as argued by Wellington (2016). A diagnosis or key that differentiates between three widespread species occurring in a particular area, without any indication of geographic variation in any of them, cannot act as a diagnosis for only a part of one of those widespread species – the taxon sensu Article 13.1.1.

In his defence of the nomen lancasteri, Wellington (2016: 74) himself admitted this fatal shortcoming by stating that

“in the context of the taxonomy proposed by Wells and Wellington in 1985 for the species of the genus Acanthophis , this differential diagnosis (via Storr 1981) was incomplete, as it did not provide explicit differential traits between A. praelongus and A. lancasteri .”

This statement undermines the entire argument for the availability of A. lancasteri by confirming that Storr did not diagnose the taxon. Wellington (2016) attempted to justify the use of A. lancasteri by stating that explicit differentiating traits were also not provided by “ Maddock et al. (2015) for A. cryptamydros vs. A. praelongus , despite the fact that a specimen of A. praelongus was included in their molecular analysis.” However, the diagnosis of A. cryptamydros in Maddock et al. (2015) did state that their new species was “Distinguishable from all other Australian Acanthophis ,” thereby plainly including A. praelongus . Moreover, based on Wüster et al. (2005), there was no starting assumption of conspecificity with A. praelongus , unlike at the time of Storr (1981) or Wells & Wellington (1985).

Storr’s mixed specimens. The second major failing of the naming of A. lancasteri is that, according to Wells & Wellington (1985) themselves, Storr’s (1981) description of A. praelongus was based on heterogeneous material belonging to two different species: these authors explicitly excluded Storr’s NT material from their concept of A. lancasteri (although, inconsistently, they described its distribution as including “the ‘Top End’ of the Northern Territory ”). However, Storr made no attempt to differentiate between Kimberley and NT specimens in his text and referred to all specimens as A. praelongus . In his account of A. praelongus, Storr (1981: 210) referred to 16 specimens under ‘Material’, of which 13 were from the Kimberley region of WA ( WAM specimen numbers R 5709, R 10628, R 11241, R 34078–79, R 37761–64, R 41457, R 46836, R 70690, R 70968) and three from two localities in the extreme northeast of the Top End ( WAM R 13517a–b) and the eastern edge of the NT near the Queensland border ( WAM R 21519). From the sample sizes provided by Storr, meristic data and scale counts were only scored for up to 15 specimens for any one characteristic presented in the description section. Storr’s unpublished data sheets housed in the WAM show that meristic data and scale counts were collected from all 16 specimens. Due to damage to some specimens, only six have full data for all characters scored or measured ( WAM R 37761–64, R 13517a–b; Table 1),

specimen, grey shading indicates those not scored or measured (Storr, unpublished data).

Registration)

(

State mm

(

)

(

) mm)

(mm

SVL)

of

Scale (# rows) Subcaudals (#) (#))

(

#

Characters

Scale (

) # scored

(#

) rugose

) (

Keels strength dorsum on

)

#)

((

#)

(

) #

color (

) to width)

(#) MBSR

of

#)

(WAM number Locality length Total Tail length SVL % (Tail Anterior Midbody Posterior Single Paired Total Supralabials Temporals Anal Ventrals Head scales strength (Anterior Posterior Preocular Postocular Subocular tip Tail Rostral (length Prefrontals Reduction anteriorly

R

R

R

R

R34079 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R37761 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R37762 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R37763 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R37764 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R41457 WA ● ● ● ● ● ● ● ● ● ● ● ●

R46836 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R70690 WA ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R70968 WA ● ● ● ● ● ● ● ● ● ● ●

R13517a NT ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

R13517b NT ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

of which the latter two are NT specimens, indicating that the NT specimens had a disproportionate influence on the ranges and averages presented by Storr. The meristic data and scale count ranges presented by Storr (1981) in the diagnosis and description of A. praelongus thus include data from both Kimberley region and NT specimens, and it is not possible to determine what specimens the numbers in the ranges refer to ( Table 1). The same applies to the text of the descriptions in Storr’s diagnostic and description sections.

As a result, Wells & Wellington’s (1985) explicit exclusion of Storr’s NT specimens from their concept of A. lancasteri , thereby characterising Storr’s material as polyspecific, invalidates the name: a description of what is explicitly stated to be a mixed sample of two species cannot act as a diagnosis for one of them (the taxon sensu Article 13.1.1.), thereby making the description non-compliant with Article 13.1. We stress the importance of the fact that Wells & Wellington (1985) themselves considered Storr’s material heterogeneous: whereas the discovery by subsequent authors that a description or definition is based on heterologous material does not make a name unavailable, it is the statement to that effect in the description of A. lancasteri itself that does.

To summarise, Storr’s (1981) concept of A. praelongus and the description he created to characterise this taxon cannot make the name A. lancasteri Wells & Wellington, 1985 available because (i) Storr’s account explicitly defines his concept of A. praelongus Ramsay, 1877 as including populations from the Kimberley, the Top End, northern Queensland and New Guinea, without any attempt to differentiate the Kimberley material, and (ii) according to Wells & Wellington (1985) themselves, Storr’s (1981) concept of A. praelongus was based on mixed data from two species and consequently cannot act as the “description or definition […] purported to differentiate the taxon ” mandated by Article 13.1.1. for one of them.

In this context, we wish to note for the record that Maddock et al. (2015) erroneously listed the NT specimens examined by Storr (1981) as A. cryptamydros from WA in their appendix. However, these NT specimens were not analysed and thus have no bearing on the diagnostic characters of A. cryptamydros .

Does A. hawkei rescue A. lancasteri? Under the description of A. hawkei, Wells & Wellington (1985: 43) provided a comparison between the juvenile patterns of A. hawkei and A. lancasteri , which would satisfy the need for “characters that are purported to differentiate the taxon” (Article 13.1.1.). However, this diagnosis does not directly accompany the introduction of A. lancasteri but precedes it, and is not referenced in the A. lancasteri species account. Instead, Wells & Wellington explicitly cited only Storr (1981) as the only source of a written diagnosis for A. lancasteri , thereby definitively excluding all other text references from that role – including their own section on A. hawkei . The combination of a lack of a definition or description directly accompanying the description of A. lancasteri and the explicit reference to Storr (1981) as the sole source of a diagnosis therefore preclude the disconnected account of the taxon hawkei from also conferring availability on the name lancasteri . It is not the responsibility of subsequent authors to search Wells & Wellington’s (1985) paper for reasons to make nomina available when the outside source explicitly and exclusively indicated by them fails to do so.

For these reasons, in strict accordance with the Code and the Commission’s recent decision ( ICZN 2020), the description of A. lancasteri does not satisfy the provisions of Article 13.1. We therefore reject Wellington’s (2016) arguments and conclude that the name A. lancasteri Wells & Wellington, 1985 is a nomen nudum. As the description of A. cryptamydros Maddock et al., 2015 ( Fig. 1A ) meets all the requirements of the Code and subsequent amendments ( ICZN 1999, 2012), it is the oldest available name under the Principle of Priority for the Kimberley death adder and must replace any erroneous usage of the nomen nudum A. lancasteri .

Figures

FIGURE 1. The four death adder species, genus Acanthophis, whose valid nomina we discuss herein. (A) A. cryptamydros Maddock et al., 2015 from the Mueller Ranges, ca. 110 km southwest of Halls Creek, Western Australia. (B) A. pyrrhus Boulenger, 1898 from 40 km south of Port Hedland, Western Australia. (C) A. hawkei Wells & Wellington, 1985 from the Barkly Tableland, Northern Territory, Australia. (D) A. antarcticus (Shaw & Nodder, 1802) from Canning Dam, near Ashendon, Western Australia. Photos by Ray Lloyd (A, B, D) and Tom Parkin (C).