Langebaanweg (LBW) is a Mio-Pliocene fossil site located on the west coast of South Africa, approximately 120 km north of Cape Town. The combination of terrestrial, riverine and marine fauna suggests that it was an estuary at the time of deposition. Early studies of the fossil phocid seal, Homiphoca capensis, from LBW suggested that it is morphologically intermediate between the monk and Antarctic phocid seal, with close affinities to the crabeater seal in particular. Here we re-examine the fossil phocid seal collection, using both descriptive and morphometric approaches, and reveal substantial variation in cranial and postcranial skeletons. The variation present in the postcranium suggests that two morphotypes are present in the sample. The morphometric analyses of the crania confirm that the LBW seals are similar in many respects, including overall size, to extant crabeater seals. However, the LBW seals appear to be more variable than any individual extant seal taxon, while examination of fine-scale shape variation in the sample identifies three distinct cranial morphotypes. Together the results of the postcranial and cranial analyses suggest the presence of two or possibly three seal taxa, indicating a greater diversity of pinnipeds at LBW than previously appreciated.

A phylogenetic analysis of the Langebaanweg seals was undertaken to better understand their relationships. The fossil phocid seals from Langebaanweg nest within the Lobodontini and form a clade that includes Ommatophoca rossii (Ross seal). The Langebaanweg seals' relationships are unresolved in both analyses. Two analyses were performed producing differing results. The prior weights analysis produced a clade that included the Ross seal (Ommatophoca rossii) + the Langebaanweg seals + the remaining Antarctic lobodontines. The implied weights analysis (k=3) produced a clade including the South American seals (Hadrokirus and Piscophoca) + the Ross seal (Ommatophoca rossii) + the Langebaanweg seals, which is part of the polytomy that includes the clade including the leopard seal (Hydrurga leptonyx) and the crabeater seal (Lobodon carcinophaga) and Acrophoca longirostis. In both analyses the monophyletic group LBW-F + LBW-D + LBW-A is retained while the monophyletic group LBW-C + LBW-B from the first analysis is replaced by the polytomy LBW-B + LBW-C + LBW-E in the second. The collapse of the monophyletic group LBW-C + LBW-B is due to its poor support (20), most likely as a result of LBW-C being incomplete caudally. Island hopping is proposed as a means for phocid seal migration to South Africa. The presence of islands along South Africa's west coast and phocid seal adaptation to a life independent of land and the use of ice as haul out sites lend support to this theory. During the Pleistocene, the decrease in local sea levels resulted in the loss of islands which may have resulted in the extinction of these seals over time.

Govender, R., Bisconti, M. & Chinsamy, A., June 2016. A late Miocene–early Pliocene baleen whale assemblage from Langebaanweg, west coast of South Africa (Mammalia, Cetacea, Mysticeti). Alcheringa 40, xxx–xxx. ISSN 0311-5518 Knowledge of post-Eocene cetaceans from Africa is very poor with almost nothing known about this group from southern Africa except for the diverse trawled ziphiids. Langebaanweg, a locality yielding prolific Miocene–Pliocene fossils on the southwestern Cape coast of South Africa, preserves terrestrial and marine biotas in juxtaposition. Palaeoenvironments vary from a marine shoreline to a lagoon and estuary and later a shallow marine environment and include several microhabitats. Fragmentary preservation of the cetacean skeletons suggests that they were transported before burial. This first detailed analysis of the Mio-Pliocene mysticete fossils from Langebaanweg uses the petrotympanic region to taxonomically identify specimens. Three un-named species of balaenopterid Mysticeti represent a Plesiobalaenoptera-like form, but it is premature to erect a new taxon based on this fragmentary material. The remaining material is too poorly preserved to be identified with confidence. Romala Govender [ rgovender@iziko. org. za ], Natural History Department, Iziko Museums of South Africa, PO Box 61, Cape Town, 8001, South Africa; Biological Sciences, University of Cape Town, Private Bag X3, Rhodes Gift, 7701, Cape Town, South Africa, Michelangelo Bisconti [ michelangelobisconti@gmail. com ], Natural History Museum of San Diego, California, 1788 El Prado, San Diego, CA 92101, USA; Anusuya Chinsamy [ anusuya. chinsamy-turan@uct. ac. za ], Biological Sciences, University of Cape Town, Private Bag X3, Rhodes Gift, 7701, Cape Town, South Africa.

Tritylodon longaevus Owen, 1884 is one of the most common members of the Lower Jurassic faunas of the Karoo Basin. The cranial and dental anatomy of this taxon is well known, but its postcranium has not been previously addressed in detail. Our analysis shows that T. longaevus shares many postcranial features with other tritylodontids that distinguish them from other non-mammaliaform cynodonts. The correlation between taxon size and postcranial anatomical traits is briefly explored among tritylodontids, showing that few morphological differences among species correlate with size. Analysis of the purported oldest remains of Tritylodon, from the Norian Los Colorados Formation of Argentina, suggests that they cannot be unambiguously assigned to this taxon, circumscribing the record of Tritylodon to African localities. Resumen . Tritylodon longaevus Owen, 1884 es uno de los taxones más comúnmente representados en las faunas del Jurásico Inferior de la Cuenca del Karoo. Este taxón es únicamente conocido a través de su anatomía craneana y dentaria mientras que su esqueleto postcraneano no ha sido previamente descripto en detalle. El presente estudio muestra que T. longaevus comparte con otros tritilodóntidos varios rasgos postcraneanos que los diferencian de otros cinodontes no mamaliaformes. También se explora aquí la correlación entre el tamaño corporal y a las variaciones en la anatomía postcraneana observadas en los tritilodóntidos, encontrándose que sólo unas pocas diferencias morfológicas entre especies se correlacionan con el tamaño. El re-análisis de los supuestos registros más antiguos (Noriano) de Tritylodon, procedentes de la Formación Los Colorados de Argentina, indica que estos restos no pueden asignarse sin ambigüedades a este taxón, circunscribiendo la distribución geográfica de Tritylodon a localidades de ...

We describe abundant new remains of the medium-sized mustelid Mellivora benfieldi from the early Pliocene site of Langebaanweg (South Africa). The specimens are from the Muishond Fontein Pelletal Phosphorite Member (MPPM) and the Langeberg Quartz Sand Member (LQSM). Novel dentognathic—upper dentition, alveolus for m2—and postcranial—humerus, metacarpal V, femur and calcaneus—information is provided. This sample enables us to review the taxonomic status of Mio–Pliocene African mellivorines. Mellivora benfieldi is distinguished from the middle–late Miocene ‘Eomellivora’ tugenensis from Ngorora Kenya by its smaller size, and a M1 protocone messially placed; from the late Miocene Howellictis valentini from Chad by greater dental size with more crowded lower premolars, and p3 with distal accessory cuspid; and from the late Miocene Erokomellivora lothagamensis from Kenya, by shorter p4 and buccolingually shorter m1 protoconid. It also differs from H. valentini and Er. lothagamensis in absence or residual presence of the m2 alveolus. We infer M. benfieldi was an opportunistic, medium-sized carnivoran with semifossorial abilities, comparable to its living relative Mellivora capensis. A cladistic analysis was performed and our phylogenetic results place M. benfieldi as the sister species of M. capensis. Mellivorini contains M. benfieldi, M. capensis, and H. valentini. Additionally, we also include Er. lothagamensis and the Indian Promellivora punjabiensis. We propose the creation of one new tribe within Mellivorinae: Eomellivorini (Eomellivora spp. + Ekorus). It shares a common ancestor with Mellivorini and is characterized by large size, a robust and sharp dentition, as well as a skeleton with cursorial adaptations.

Giant mustelids are a paraphyletic group of mustelids found in the Neogene of Eurasia, Africa and North America. Most are known largely from dental remains, with their postcranial skeleton mostly unknown. Here, we describe new craniodental and postcranial remains of the large lutrineSivaonyx hendeyiand the leopard-size guloninePlesioguloaff.monspessulanusfrom the early Pliocene site Langebaanweg, South Africa. The new material of the endemicS. hendeyi, includes upper incisors and premolars, and fragmentary humerus, ulna and a complete astragalus. Its postcrania shares more traits with the livingAonyx capensisthan the late MioceneSivaonyx beyifrom Chad.Sivaonyx hendeyicould therefore be tentatively interpreted as a relatively more aquatic taxon than the Chadian species, comparable toA. capensis. The new specimens ofPlesiogulocomprise two edentulous maxillae, including one of a juvenile individual with incomplete decidual dentition, and a fragmentary forelimb of an adult individual. The new dental measurements point to this form being amongst the largest specimens of the genus. Both P3-4 differs from the very large speciesPlesiogulo botorifrom late Miocene of Kenya and Ethiopia. This confirms the existence of two distinct large species ofPlesioguloin Africa during the Mio/Pliocene,P. botoriin the Late Miocene of Eastern Africa (6.1–5.5 Ma) andPlesioguloaff.monspessulanusat the beginning of the Pliocene in southern Africa (5.2 Ma). Lastly, we report for the first time the presence of bothSivaonyxandPlesioguloin MPPM and LQSM at Langebaanweg, suggesting that the differences observed from the locality may be produced by sedimentation or sampling biases instead of temporal replacement within the carnivoran guild.