Perameles auratus Ramsay, 1887

Parnaby, Harry & Gill, Anthony C., 2021, Mammal type specimens in the Macleay Collections, University of Sydney, Zootaxa 4975 (2), pp. 201-252 : 211-214

Perameles auratus Ramsay, 1887

Proc. Linn. Soc. N.S.W. (ser. 2) 2 (3), 551. (30th November 1887).

Description read at the 31st August 1887 meeting of the LSNSW.

Current name. Golden Bandicoot Isoodon auratus ( Ramsay, 1887) following Jackson & Groves (2015).

Taxonomic status. Recognised as either a species or subspecies of I. obesulus ( Shaw, 1797) throughout most of the past century, but often accepted as a valid species in recent decades, see Jackson & Groves (2015).

Syntype. M.468, adult male, skull extracted, puppet skin with large scrotum and tail stub ( Fig. 3 ). In 2016, an old label, evidently Ramsay’s original, was found attached to skin M.468 and states “type of the species” and is initialed “Ed.P.R.” [= E. P. Ramsay], see Fig. 1c . That tag has subsequently been detached from the skin. A skull and mandibles labeled M.468 currently associated with skin M.468 is a possible mismatch ( Fig. 4 ), see Comments below. The skull marked M.468 has fully erupted and worn dentition and is intact other than missing the right zygomatic arch and is the skull illustrated in figs 62–65 of Lyne & Mort (1981) as being the “type”. Mahoney & Ride (1988) refer to M.468, study skin and skull as “the holotype ”, which could be interpreted as lectotype designation by inference of a holotype (Article 74.6, the Code), given the possibility that syntypes exist. We leave lectotype designation to those undertaking taxonomic research. We do not recognise the skull currently associated with skin M.468 as being the syntype skull. Its association with the skin requires confirmation by a specialist in Isoodon taxonomy or might be resolved using DNA sequencing.

Other material. M.469, female, study skin. Skin tag has “skin (). skull () on M368?”, the latter presumably an error for M.468. A skull labelled M.469 ( Fig. 4 ), fourth molars not fully erupted, is thus doubtfully associated with skin M.469. The MAMU Register entry for M.469, done in the 1960s, states, “skin only, skull attached to M.468?”. Since that entry, a second skull has apparently been found in the Collection and doubtfully matched with skin M.469 but the basis of this match, when it was done, and by whom is not recorded in the database.

The type status of skin M.469 and associated skull remains undetermined. It might be the female skin from Derby listed in the MAMU 1890s Catalogue but it might be a third, previously overlooked female for which no collector or date are recorded, see Comments below.

Type locality. “The neighbourhood of Derby, N.W. Australia ” (Ramsay), Western Australia.

Comments. Ramsay’s account focused entirely on a specimen with a tail stub for which he does not indicate the sex. Study skin M.468 (a male) is almost certainly that specimen. Ramsay’s original tag was still attached to skin M. 468 in 2016 but the skull currently associated with that skin is probably mismatched from another individual, as yet unidentified.

Two main issues impede identification of type material of I. auratus in the Collection. First, is male skin M.468 a holotype or syntype?; second, which skull currently in the Collection, if any, belongs with type skin M.468? We have not resolved the second issue but identify key aspects for further investigation.

The 1890s Catalogue lists only two specimens of I. auratus , adult skins of a male and female from Derby (the collector is not given). The male skin is assumed to be M.468 but the identity of the female skin now in the Collection is less clear. It might be the female listed in the Catalogue or an undocumented third individual, as discussed later. The female skin listed in the Catalogue was either examined by Ramsay or received by Macleay after Ramsay’s presentation of the account at the August 1887 meeting of the LSNSW. It might have arrived in the second consignment of specimens from Derby at an undermined date in 1887, or in 1888 when Froggatt returned to Sydney. We have not found documentation of the number and dates of shipments of natural history material sent from Derby by Froggatt to Macleay. The two references that we have found are both vague and ambiguous. Mammals collected by Froggatt are mentioned at two meetings of the LSNSW held in 1887. Anonymous (1888: 981) records that at the 26th November 1887 meeting, Masters exhibited mammals recently received that Froggatt had sent from Derby, that included “Two specimens of Hapalotis Boweri Ramsay ; Perameles auratus, Ramsay ; Perameles n. sp. (?); ….”. Crucially, we cannot be certain that Masters exhibited only those mammals obtained from the second shipment, as he might have exhibited a mixture from both shipments. It is also unclear whether “ Perameles auratus ” refers to one or more specimens. Further, whether “ Perameles n. sp. (?)” refers to M.469 or an entirely different specimen of another species, perhaps later deemed not be a new species. In a paper presented at the December 1887 meeting, Macleay (1888) noted that he had so far received two shipments of Froggatt’s Derby material. Although he stated that the first shipment from Froggatt was noted in the June meeting of the LSNSW, the first mention of Froggatt’s Derby material in the Proceedings was at the August meeting. At the December 1887 meeting, Macleay (1888) stated that he had “only just” received the second shipment and that “mammals of this collection were exhibited at our last meeting”, referring to the meeting of 30th November 1887. This might imply, though not necessarily, that additional material of I. auratus arrived after Ramsay’s description was presented at the meeting of 31st August 1887 but it is also possible that Ramsay initially received several specimens of I. auratus .

The fact that Ramsay did not provide a description of an intact tail implies that he did not have another specimen with a tail. Alternatively, he might have focused on one specimen and ignored others. Ramsay has a track record of abbreviated mammal descriptions that fixate on describing one specimen and little else, even for species later determined to involve a type series. In any case, the possibility remains that Ramsay also examined an adult female. Doubt about whether Ramsay had a syntype series is resolved by adoption of Recommendation 73F of the Code, i.e. an assumption of syntypes when more than one specimen is suspected. The only practical consequence is whether skin M.468 is recognised as a holotype or lectotype.

Locating the skull belonging to type skin M.468 remains a key issue that we have not resolved. The MAMU 1890s Catalogue does not indicate whether the skulls were extracted from the two skins. It is not known if Ramsay extracted a skull for his description but it seems likely that he did. He did not provide a description or measurements of the skull but was able to examine the rear molars. The jaws of bandicoots do not open wide enough for inspection of the rear molars unless the cheeks are cut or the skull extracted (Dr Kenny Trevouillon pers. comm.).

Establishing the correct skull match with type skin M.468 and the identity of the second skin is complicated by the prospect, overlooked prior to our study, that a third I. auratus specimen in alcohol was in the Collection prior to the 1920s. The MAMU Donations Book entry for 27th September 1926 lists one I. auratus sent to the AM for skull extraction and identification (skin and skull returned 12th November 1929), along with two I. macrourus . The annotation next to the I. auratus entry in September 1926 states “Parcel from Tank”, suggesting that the specimen was removed from an alcohol storage tank. We interpret “parcel” as a specimen wrapped in cloth, making it more likely to have been overlooked when the Catalogue was prepared in the 1890s. This suggests that either the entry for the female skin in the MAMU 1890s Catalogue had neglected to indicate “spirit”, or that an additional female specimen was in the Collection. If there was a third specimen in alcohol, the collector and locality have not been recorded.

Two skins but only one skull of I. auratus were registered in the 1960s and were probably assumed to be the two individuals listed in the 1890s Catalogue. A second unlabeled and unnumbered skull was found in the Collection at an unknown date after registration. If three specimens (a male and two females) were in the Collection prior to the 1920s, then one skin and one skull are now missing. The missing skin and skull could have been from two different individuals, including the skull belonging to male type skin M.468, given that skull morphology of I. auratus is not sexually dimorphic ( Lyne & Mort 1981) and skulls cannot be assigned to sex. Skin M. 469 might be the one from Derby listed in the 1890s Catalogue , or the alcoholic female turned into a skin at the AM but for which the locality was not recorded. The specimen might have been collected by Froggatt, but other scenarios, though less likely, cannot be excluded given the poor documentation of specimens to and from the Collection after the early 1880s. The specimen might have entered the Collection at any time from the 1880s to the early 1920s. Froggatt donated mammal specimens that he collected in 1887 from north west Australia to the AM in 1932 and might also have donated material to the MAMU, for which the documentation has not been located. Alternatively, it might have been an exchange from another source for which the documentation has been lost.

A further consideration is that the two I. auratus specimens now in the Collection possibly represent different taxa. Travouillon & Phillips (2018) recognised two morphologically distinct forms of I. auratus , a “Kimberley” form and an inland form. Froggatt had collected extensively in both inland and subcoastal areas by early September 1887 ( Froggatt 1934) and would have collected within the distribution of both suspected forms of I. auratus . Both specimens of I. auratus in the MAMU were examined by Dr Kenny Travouillon (Western Australian Museum, pers. comm. 2016) as part of ongoing taxonomic research. He suggests, based on skin and skull morphology, that the smaller skull currently labelled M.469 could belong with skin M.468, but this requires further research into morphological variation in populations of I. auratus .

Skull measurements of the “typical specimen” (= type specimen) of I. auratus reported by Thomas (1904: 228) were provided by E.R. Waite (then of the Australian Museum) and these dimensions are consistent with skull M.469, see Table 2 . Although the measurements given in Table 2 suggest a trivial size difference between the skulls, M.469 is clearly the smaller skull and a good match to those of Waite ( Fig. 4 ). It is clear that Waite measured skull M.469 but whether that skull was from the male or female skin(s) remains unknown. Crucially, this depends on whether Waite encountered one or two skulls. The “typical specimen” cited by Thomas (1904) does not necessarily equate to the tail-less skin M.468 examined by Ramsay. If two skins were present when Waite took the measurements, both could have been treated as “typical” specimens, i.e. “co-types”. It is possible that Ramsay labelled each as “type of the species”, a practice evident from his original labels still attached to mammal syntype skins in the AM.

In conclusion, three likely scenarios emerge from the quagmire of uncertainty, depending on whether Waite encountered one or two dry skins. First, a simple situation emerges if the 1890s Catalogue entry had simply neglected to add “skin in spirit” against the female skin. In that case, Waite could only have encountered one dry skin and one skull, those of the tail-less male described by Ramsay (assuming no other undocumented specimens were in the Collection at that time). This would support the preliminary conclusion of Travouillon that the skull currently marked M.469 belongs to skin M.468. Second, Waite encountered two dry skins, which generates many uncertainties. Under this scenario, a female skin and skull have been lost or exchanged from the Collection. Waite might have assumed that both skins were co-types but if only one skull had been extracted, from which skin? If both skulls had been extracted, their correct association with the skins might have been muddled before Waite’s visit in c. 1903, or subsequently. It seems that neither of the skulls would have been marked with names or numbers and Ramsay did not publish skull or dental measurements to enable comparisons. Third, Waite encountered two dry skins, one now lost, and a third specimen, a female in alcohol, was converted to a skin and skull in the 1920s but the locality and collector remain unknown.

A simple path through such uncertainty for a taxonomic specialist would be to assume that Ramsay had a syntype series; designate the male skin as lectotype; and designate one of the two skulls in the Collection as the lectotype skull once the taxonomic status of the two suspected forms of I. auratus is resolved.

Figures

FIGURE 1. Examples of 19th century MAMU specimen tags.A, Masters tag post-1889 (M.386, possible syntype of Halmaturus crassipes Ramsay); B, characteristically compact Masters tag (M.1155, Isoodon obesulus [Shaw]), and C, Ramsay tag (M.468, syntype of I. auratus [Ramsay]). Not to scale.

FIGURE 3. Skin of M.468, adult male syntype of Isoodon auratus (Ramsay, 1887). Scale bar = 2 cm. (© Chau Chak Wing Museum, photo Stuart Humphreys 2016).

FIGURE 4. Size difference between the two skulls (left: MAMU M.469 and right: MAMU M.468) which are suspected potential matches to the syntype skin (M.468) of Isoodon auratus (Ramsay, 1887). Scale bar = 1 cm. (© Chau Chak Wing Museum, photo Stuart Humphreys 2016).