Anoplotherium, CUVIER, 1804 B

Hooker, J. J., 2007, Bipedal browsing adaptations of the unusual Late Eocene-earliest Oligocene tylopod Anoplotherium (Artiodactyla, Mammalia), Zoological Journal of the Linnean Society 151 (3), pp. 609-659 : 613-615

GENUS ANOPLOTHERIUM CUVIER, 1804B

ANOPLOTHERIUM LATIPES ( GERVAIS, 1852)

vp1972 Ronzotherium ; Ford, pl. 2, fig. B–C, pls 3–4.

Types: Gervais (1852: plate explanation 36, pp. 1–2) quoted Gervais (1850) for the origin of the name Eurytherium latipes and this is the date usually quoted for the species. However, the name is not mentioned in this reference. The name must therefore date from Gervais (1852: plate explanation 36, pp. 1–2). This raises a problem of priority as Pomel (1851) named Anoplotherium platypus for what Gervais regarded as his E. latipes . However, Pomel’s type description of A. platypus only stated that it was a three-toed species the same size as A. commune , but without figuring or mentioning any specimens. It could therefore be confused with A. laurillardi , which occurs at the same site and is only slightly smaller than A. commune . For this reason, A. platypus Pomel, 1851 is best regarded as a nomen dubium and should not take priority over Eurytherium latipes Gervais, 1852 . Gervais (1852: plate explanation 36, pp. 1–3, unnumbered figure and pl. 15, fig. 10, pl. 36, fig. 1) characterized the species more clearly. In the BMNH, where much of Bravard’s collection is located, the subject of Gervais (1852: pl. 15, fig. 10), a ‘right’ metatarsal II, can be tentatively identified as belonging to the left composite foot numbered BMNH.30600c, accepting reversal of the figure. Breakage and distortion of an individual nature are the basis for its recognition. Unfortunately, the distal half of this specimen has been restored in plaster. Another M/T II, the subject of Gervais’s (1852) pl. 36, figs 2–4, has not been located in the Bravard Collection in the BMNH. Of Gervais’s (1852, pl. expl. 36, p. 3) three figures of reconstructed feet, the left figure (see also Gervais, 1859: 168, fig. 17) is of a relatively small manus with slightly waisted metacarpals and has been identified as Diplobune secundaria by de Bonis (1964: 20–22). The specimen appears to be BMNH.30600d, although the figure would have to have been reversed and some phalanges added to the mount. The central figure of a larger manus appears to represent Anoplotherium (see also Gervais, 1859: 168, fig. 18). The outlines of some of the bones resemble BMNH.30600a (M/C III is plaster), which according to size consists entirely of A. laurillardi . The right-hand figure (see also Gervais, 1859: 168, fig. 19) closely resembles a left composite pes (BMNH.30600b), which would have to have been reversed to a right in the illustration. de Bonis (1964: 19) suggested that most of the bones of this pes belong to A. laurillardi , except some of the tarsals, which he thought were closer to A. latipes . In fact, apart from the calcaneum and astragalus, all the bones match A. latipes for size, including the critical M/T II. M/T II and III are larger than these bones of A. laurillardi figured by de Bonis (1964: pl. 3, fig. 3). All these specimens constitute the syntypes. The syntype series must exclude the astragalus and calcaneum, the subjects of Gervais’s (1852) pl. 36, figs 4–5, as doubt is expressed as to their identification in his text, although not in the identification on the plate itself. The type locality is La Débruge, Vaucluse, France, and the type horizon comprises unnamed lignites of middle Priabonian (Late Eocene) age (Mammalian Reference Level MP18). The fact that one of Gervais’ figures represents a different genus ( Diplobune ), whilst others are composites of two different species of Anoplotherium , makes it important to select a lectotype. Accordingly, the left M/T II (BMNH.30600b), part of the composite foot figured by Gervais (1852: pl. expl. 36, p. 3, right figure) is selected here as lectotype of Anoplotherium latipes ( Gervais, 1852) ( Fig. 1E–G ). The genus Eurytherium was synonymized with Anoplotherium by Schlosser (1883b: 153–154), an action followed by nearly all subsequent authors.

Material

Specimen 1: Incomplete skeleton of immature animal from the log bed, top of the lower Hamstead Member (earliest Oligocene), Bouldnor, Isle of Wight, UK ( Hooker et al., 2004). This bed is referred to mammal level Ham 3 by Hooker (in press). The skeleton comprises the following elements (museum repositories and numbers are appended, as is a published citation).

Fragmentary right dentary in two pieces, with P 2 -M 1 and M 3 trigonid (IWCMS. 1999.128);

right I 1, P 1, P 2, P 3, M 1, left P 3, P 4 (IWCMS. 1999.128); fragments of palate (IWCMS. 1999.128);

fragment of frontal (IWCMS. 1999.128);

fragment of supraoccipital region (IWCMS. 1999.128); fragment of atlas (IWCMS. 1999.128);

cervical vertebrae 4 and 7 (IWCMS. 1999.128); thoracic vertebra 1, with separated posterior epiphysis, embedded in pyrite block (IWCMS. 1999.128); thoracic vertebrae 3?, 4?, 6?, 7?, 11? and 12? (IWCMS. 1999.128);

lumbar vertebrae 2? and 4? (IWCMS. 1999.128); lumbar vertebra 5? or 6?, neural spine with right postzygapophysis (IWCMS. 1999.128);

anterior caudal vertebra (IWCMS. 1999.128); posterior caudal vertebra (SMNS.42098);

three complete vertebral epiphyses (2 anterior thoracics and one distal anterior caudal) and five fragments (IWCMS. 1999.128);

26 rib fragments, including proximal ends of left 4? and 5? and left and right 8? or 9? (IWCMS. 1999.128); left scapula (SMNS.42098) (figured Ford, 1972);

right scapula in three pieces (IWCMS. 1999.128); proximal epiphysis of right humerus (IWCMS. 1999.128);

left humerus lacking proximal end (SMNS.42098) (figured Ford, 1972);

proximal left ulna (SMNS.42098) (figured Ford, 1972); right ulna lacking distal end (IWCMS. 1999.128); proximal left radius (SMNS.41960a);

proximal right radius (IWCMS. 1999.128);

distal epiphysis of right radius (IWCMS. 1999.128); left scaphoid (SMNS.41992);

left unciform (BMNH. M42661 );

left metacarpal II (SMNS.42098);

distal left metacarpal III (SMNS.42098) (figured Ford, 1972);

distal left metacarpal IV (IWCMS. 1999.128); proximal left metacarpal IV (SMNS.42066a);

right metacarpal III (IWCMS. 1999.128);

right metacarpal IV (IWCMS. 1999.128);

manual right first phalanx IV (IWCMS. 1999.128); manual left or right second phalanx III or IV (SMNS.42098) (figured Ford, 1972);

manual? left or right second phalanx III or IV, parasagittal half (SMNS.42038a);

three fragments of left os innominatum of pelvis including acetabulum (IWCMS. 1999.128);

left femur lacking proximal end and distal epiphysis (IWCMS. 2002.41);

right femur (IWCMS. 1999.128Q);

left tibia (IWCMS. 1999.128Q);

right tibia (IWCMS. 1999.128Q);

proximal epiphysis of left fibula(IWCMS. 1999.128Q); distal left fibula (IWCMS. 1999.128Q);

proximal epiphysis of right fibula (IWCMS. 1999.128Q);

distal right fibula and fragment of left or right fibular shaft (IWCMS. 1999.128Q);

left calcaneum (IWCMS. 1999.128);

left cuboid (IWCMS. 1999.128);

left ectocuneiform (IWCMS. 1999.128);

right mesocuneiform (IWCMS. 1999.128);

left metatarsal II (IWCMS. 1999.128);

left metatarsal III (IWCMS. 1999.128);

right metatarsal II (IWCMS. 2000.390);

pedal left first phalanx III (IWCMS. 1999.128);

A = anterior; H = height; L = length; P = posterior; Trans Proc = transverse processes.

pedal right? first phalanx III? (IWCMS. 1999.128); sesamoid (IWCMS. 1999.128).

Specimen 2: Left humerus lacking distal end, Beckles Collection, Bouldnor Cliff, assumed lower Hamstead Member (‘Hempstead’) (BMNH.M4450) ( Fig. 10 ).

Specimen 3: Distal right radius and ulna, apparently associated, Hastings Collection, ‘N.W. Isle of Wight’, probably also lower Hamstead Member, Bouldnor Cliff (BMNH.30029) ( Fig. 14A–J).

Figures

Figure 1. Anoplotherium latipes. A–D, Ham 3 skeleton, log bed, lower Hamstead Member, Bouldnor Formation, Bouldnor, Isle of Wight, UK (IWCMS. 1999.128). Bones showing tooth puncture marks, indicated by arrows. A, manual right first phalanx IV, distal end in dorsal view. B, anterior thoracic vertebra (3?) in left lateral view. C and D, mediodistal portion of left ischium in dorsal (C) and ventral (D) views. E–G, lectotype left metatarsal II, Late Eocene lignites, La Débruge, Vaucluse, France (BMNH.30600b) in anterior (E), posterior (F) and lateral (G) views. Coated with ammonium chloride. Scale bar = 50 mm.

Figure 10. Anoplotherium latipes. Ham 3 skeleton, humeri and radii. A–E, left humerus lacking proximal end (SMNS.42098). F, right humerus, proximal epiphysis (IWCMS. 1999.128). G, right proximal radius (IWCMS. 1999.128). H, left proximal radius (SMNS.41960a). Views are anterior (A), lateral (B, F), medial (C), posterior (D), distal (E) and proximal (G, H). Coated with ammonium chloride. Scale bar = 50 mm.