Megalotragus undetermined

Brophy, Juliet K., de Ruiter, Darryl J., Fortelius, Mikael, Bamford, Marion & Berger, Lee R., 2016, Pleistocene Bovidae (Mammalia) from Malapa, Gauteng Province, South Africa, Palaeontologia Electronica 35 (8), pp. 1-22 : 7-9

MEGALOTRAGUS sp.

Material. Eight specimens exhibit morphological characteristics consistent with Megalotragus sp. , an extinct giant alcelaphine. UW 88-1299 consists of a right maxillary fragment with a M 2 and M 3 ( Figure 5 ). UW 88-1205 consists of a left maxillary fragment with a M 1 ( Figure 5 ). UW 88-746 is a maxillary fragment of a subadult with a left M 2 and an erupting M 3 ( Figure 6 ). Malapa UW 88-1311 is an isolated, right P 4 .

Four mandibular fragments were recovered from Malapa that represent Megalotragus sp. UW 88-1249 and UW 88-1250 are right and left mandibular fragments lying adjacent to each other in the matrix suggesting they are the same individual. The right mandibular fragment, UW 88-1249, consists of the hypoconulid of a broken M 3 and part of the horizontal and ascending ramus. UW 88-1250

BROPHY: BOVIDAE FROM MALAPA consists of the mandibular fragment surrounding the left P 3, P 4, and M 1. The third specimen is a left mandible fragment with an unerupted P 4, UW 88- 556. UW 88-1251 is an almost complete right mandible with dp 3, dp 4, M 1, M 2, M 3 ( Figure 7 ).

Description. The teeth are hypsodont and have simple infundibula, rounded lingual maxillary lobes, moderately pointy buccal mandibular lobes, and moderately well-developed ribs and styles. While broken, the metastyle of the M 3 of UW 88-1299 appears to expand distally, a characteristic of Megalotragus sp. ( Brink, 2005). Both of the UW 88- 1299 molars are damaged making direct metric comparison difficult. The occlusal surface of UW 88-1205 is complete enough for EFFA to be performed. The results of the DFA classified UW 88- 1205 as Alcelaphini with a 0.029 typicality probability at the tribe level and as Alcelaphus buselaphus with a 0.005 typicality at the species level. These results suggest that this specimen is most similar to the tribe Alcelaphini . However, the low species level typicality suggests that the occlusal outline of UW 88-1205 is not typical of one of the four extant alcelaphines in the reference database. EFFA classified the M 2 of UW 88-746 as Alcelaphini with a 0.417 typicality probability and as Connochaetes taurinus with a 0.102 typicality. These results suggest that UW 88-746 is an alcelaphine but not one of the four reference species. The M 3 hypoconulid of UW 88-1249 is clearly hypsodont. The P 4 hypoconid of UW 88-1250 and UW 88-556, while partially obstructed, is hyper-robust. EFFA classified the M 1 of UW 88-1251 as belonging to the tribe Alcelaphini and as the genus/species C. taurinus with 0.061 and.089 typicality, respectively. Once again, these results suggest that this specimen is most similar to an alcelaphine though atypical for the alcelaphine species in the reference database. Comparisons. The Malapa specimens were compared with Megalotragus sp. from Swartkrans Members 1-3, Kromdraai A, Sterkfontein Member 4, and Makapansgat; the characteristics of the Malapa specimens described above are consistent with Megalotragus sp. ( Gentry and Gentry, 1978; Vrba, 1976; Brink, 2005). The Malapa specimens are not consistent with the traits of Connochaetes . Specifically, the P 4 hypoconid in UW 88-1250 and UW 88-556 is hyper-robust compared to Connochaetes and does not have dental constriction of

PALAEO- ELECTRONICA.ORG the P 4 hypoconid as seen in Connochaetes ( Brink, 2005) . Tooth size was not a conclusive factor for establishing genus/species of the Megalotragus sp. Malapa teeth due to overlap in tooth size between Megalotragus and Connochaetes specimens ( Table 5). Only the size of the M 2 from UW 88-1251 falls outside of the range of Connochaetes sp. and within the normal range of size variation for the Megalotragus sp.

Figures

FIGURE 5. Malapa specimen UW 88-1299, right maxillary fragment with M2 and M3 (left). Malapa specimen UW 88- 1205, left maxillary fragment with M1 (right).

FIGURE 6. UW 88-746 maxilla with left M2 and M3.

FIGURE 7. Lateral (left) and occlusal view (right) of UW 88-1251.