Mesoplodon guentheri Krefft, 1871b

Parnaby, Harry E., Ingleby, Sandy & Divljan, Anja, 2017, Type Specimens of Non-fossil Mammals in the Australian Museum, Sydney, Records of the Australian Museum 69 (5), pp. 277-420 : 343

Mesoplodon guentheri Krefft, 1871b

Ann. Mag. Nat. Hist. (ser. 4) 7: 368, figs 1–2. (1 May 1871).

Common name. Strap-toothed Beaked Whale.

Current name. Mesoplodon layardii (J. Gray, 1865c) , following Perrin (2009g).

Holotype. All material by subsequent determination. The holotype is thought to be the following material, but further verification is required: PA.358, PA.358.001, skull and artificial dentaries, the skull has also been labelled PA.363; PA.358.002, near complete, partly articulated skeleton, (pelvic bones listed in Palmer Register not yet located); PA.359, original dentaries; PA.363, three hyoid bones; PA.364, three sternum bones.

The original entries written by Palmer in the P Register for PA.358 and PA.359 are “ Mesoplodon Thomsonii, Little Bay nr Long Bay ” and the Remarks column lists 358 as “Skeleton. Jaws restored” and for 359 “fractured jaws of above”. Palmer did not mark either entry as being a type. A subsequent entry against PA.358 and PA.359 in 1918 signed by A. R. McCulloch states: “evidently the holotype of the name Callidon guntheri ”. Bannister (1988b) cites registration numbers for the holotype as “P358, 359, and 364 skeleton” but this reflects confusion about the registration numbers and material in the collection at that time .

The holotype was stranded in late 1870 ( Scott, 1873: 116). The sex of the holotype was not recorded in the original description (perhaps because the body was “very much hacked and lacerated”), or in the Palmer Register entry. Sexual dimorphism was later recognized in this taxon and the specimen was considered to be female (e.g., by J. Ogilby, 1892).

Condition. PA.358.001: damaged whole skull, missing anterior part of rostrum which has been replaced by wood/ cast, left side of braincase missing and replaced with wood/ cast; both dentaries and teeth are artificial, modelled from wood. PA.358.002: damaged whole skeleton; some ribs are broken, but have been repaired. The skeleton is partially articulated (rib cage separate to vertebrae). PA.359 (original dentaries): incomplete and damaged dentaries: both dentaries missing teeth, left dentary is broken in two places, wired together; right dentary is fragmented and wired together; missing coronoid and condylar processes; angular process broken off but wired together.

Type locality. Little Bay, near Long Bay, Sydney, NSW ( Krefft, 1871b,c).

Comments. Krefft’s brief description was based on one complete skeleton of a whale which he states was 18 feet long. A drawing of a tooth accompanied his description but he did not provide cranial measurements or illustrations of the skull. He also mentioned some preserved viscera, which are no longer in the collection. Krefft stated that the skeleton was complete but that the body was badly lacerated. P Register annotations made in the late 19th and early 20th century indicate uncertainty about the identity of Krefft’s original specimen, which remains unresolved pending a comprehensive assessment of Mesoplodon material at the AM and archival photographs.

Gray (1871a), in a footnote to Krefft’s paper ( Krefft, 1871b), proposed the genus Callidon , based on tooth morphology of the holotype of guentheri , which he believed was radically different from his concept of tooth morphology of Mesoplodon . However, Flower (in Krefft, 1871c) expressed the view that such differences in tooth morphology were likely to be due to age or sex. Krefft (1873c) does not mention guentheri in his comprehensive summary of Australian whale taxa, implying that he no longer recognized it as a valid species. (Article 32.5.2.1 of the Code dictates that diacritic marks of German names must be amended, thus güntheri becomes guentheri .)