From its description in 1863 until the 1920s, the authority for the name Spizaetus philippensis was almost universally agreed to be J. H. Gurney, but from the 1930s it has normally been ascribed to J. Gould. This paper demonstrates that this alteration of the authority was incorrect; it should be J. H. Gurney. The two syntypes of the taxon are currently held by the Natural History Museum at Tring.
In his book on the Birds of Asia, Gould (1863) included a plate labelled Spizaëtus alboniger, depicting this bird with an accompanying text in which he explained that so little was known about the crested eagles of the genus Spizaëtus that he had asked J. H. Gurney (1819–90) for help:
‘I have not hesitated, therefore, to seek the aid of a gentleman (J. H. Gurney, Esq.) who has devoted much attention for many years to the birds of the Raptorial order; and this has been most courteously accorded to me, in the form of a monograph of the Indian species, which I consider I may most appropriately publish as an accompaniment to my illustration of the Spizaetus alboniger.’
Gurney's monograph included details of seven species of ‘Asiatic Spizaëti’ that he considered recognisable, all of which were included by Gould (1863). One of these species appeared to Gurney to be undoubtedly distinct, but previously unfigured, and he provided descriptions of the two specimens then in the Norwich Museum that he referred to it; as these specimens came from the Philippine Islands, he proposed the name Spizaëtus philippensis for them. In the years immediately following, key taxonomic and faunal works by Gray (1869), Sharpe (1874) and Walden (1875) all attributed the authority for the name philippensis to Gurney, though the first and last named both placed it in a different genus, Limnaëtus. Walden’s (1875) paper further included a plate (XXIV) of the species by Joseph Smit, illustrating the type specimen in the Norwich Museum for which Gurney had provided the most detailed description.
Later in his career, Gurney (e.g., 1884) continued to attribute the name philippensis to himself in taxonomic lists, and Gould seemingly never challenged this prior to his death in 1881. Through the end of the 19th century and well into the 20th, recognition of the name's authority as Gurney continued (e.g., Sharpe 1899, Swann 1922, Swann & Wetmore 1933, Hachisuka 1934), including in the deeply researched card index of Richmond (1992), not published until late in the century but compiled prior to his death in 1932. (Richmond's relevant card for S. philippensis is available at http://zoonomen.net/cit/RI/SP/Sitt/sitt00643a.jpg.) However, Stresemann (1924: 432) gave the authority as ‘Gould [ex Gurney M.S.]’ and Peters (1931) without explanation attributed Spizaetus philippensis just to Gould, an opinion maintained in the second edition of this influential work (Stresemann & Amadon 1979) as well as by Wolters (1976). Although this stance was cogently refuted by Preleuthner & Gamauf (1998), referencing Art. 50(a) (ICZN 1985), in a footnote to their paper describing a second philippensis subspecies, pinskeri, all the major world checklists have continued to follow Stresemann & Amadon (1979) in ascribing philippensis to Gould (Dickinson & Remsen 2013, del Hoyo & Collar 2014, Clements et al. 2022, Gill et al. 2022).
This latter course of action is clearly incorrect for the following reasons: (1) in the first paragraph of his text, Gould (1863) stated that he sought the aid of Gurney and was publishing his ‘monograph’; (2) Gould then stated ‘The following are Mr. Gurney’s observations:-’ and every paragraph in the remaining text is in quotation marks, indicating Gould is quoting Gurney directly, including where Gurney himself is quoting other authors; (3) for S. philippensis, the descriptions of two specimens are included, both held by the Norwich Museum, and there is no mention of them having been loaned to Gould or otherwise seen by him to describe. Despite the comment attached in 2004 to the philippensis species account on the Zoonomen website http://zoonomen.net (accessed 17 November 2022) that ‘Gould used a Gurney MS. name and ‘credited’ him, but the description is apparently by Gould himself and there are no grounds for giving credit to Gurney’, this emphatically is not the case. There seems no doubt that, under Art. 50.1.1 (ICZN 1999), Gurney is unambiguously the correct authority for the name S. philippensis, which under current taxonomy is assigned to the genus Nisaetus (Haring et al. 2007, Lerner et al. 2017).
Although the Norwich Museum bird of prey collection, including the two specimens mentioned in Gurney's type description of S. philippensis (Gould 1863), was passed to the Natural History Museum in the mid 1950s, Warren (1966) failed to include mention of the taxon in her subsequent published types list. However, this omission was subsequently rectified by a curator in the annotated version of the list held in the NHMUK bird collection, as follows:
‘philippensis – Spizaetus philippensis Gould 1863 Birds of Asia, pt 15, in text to pl 10 labelled Spizaetus alboniger. HOLOTYPE, Adult. Reg. no. 1955.8(sic, should be 6).N.20.423. Philippines. Gurney collection ex Verreaux. The paratype mentioned in the description 1955.8(sic, should be 6).N.20.424 is also in the collection.’
This text is also shown in the NHMUK online bird types catalogue https://www.nhm.ac.uk/research-curation/scientific-resources/collections/zoological-collections/type-specimens-of-birds/index.html (accessed 1 December 2022). However, treatment of the two specimens 1955.6.N.20.423 and 424 as holotype and paratype, respectively, rather than as syntypes appears unjustified. In the original description, although Gurney described what he referred to as an ‘adult female’ (now NHMUK 1955.6.N.20.423) first and in greater detail, his remarks on ‘the second and apparently less adult specimen’ (now NHMUK 1955.6.N.20.424) follow directly on and are perfectly adequate, stressing its overall similarity to the first while flagging relatively minor points of difference in crest development, colour and markings (Gould 1863). Here and subsequently (e.g., Gurney 1877), he appears to have been in no doubt in presenting both equally as exemplars of his new taxon.
Acknowledgements
We are most grateful to Edward Dickinson, Steven Gregory and Frank Rheindt for their comments on the correct authority in this case, as well as to Norbert Bahr and Murray Bruce for formally refereeing the paper.